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Octreotide is recommended as a second-line treatment for patients with congenital hyperinsulinism (CHI), especially for those who do not respond to diazoxide or surgical intervention. Studies on the adverse effects of octreotide in large cohorts are still scarce. We evaluated the safety of octreotide in CHI patients by reviewing cases from the two largest centres in China that specialize in the management of this condition. Our study analysed adverse events in 122 CHI patients on octreotide, with a 93% success rate for the therapy alone. The mean maximum dose of octreotide was 13.1 ± 6.5 µg/kg/day, with no difference in required doses between diffuse and focal lesion patients. Common side effects were hepatobiliary injuries (20.5%), gastrointestinal symptoms (31.1%), and transient hyperglycaemia (49.2%), with one case of necrotizing enterocolitis. Adverse event rates increased in patients treated with intermediate octreotide dose to those treated with higher doses, rising from 58% at doses of 5-10 µg/kg/day to 100% at doses exceeding 20 µg/kg/day. Patients experiencing adverse events received significantly higher doses., Conclusion: Octreotide effectively maintained blood glucose levels in diazoxide-unresponsive CHI patients without serious adverse effects, across all subtypes. Our study suggests that intermediate octreotide dosing is associated with a lower incidence of adverse events. We recommend close monitoring of patients receiving octreotide, especially during the initiation phase and when higher doses are administered., What Is Known: • Octreotide is a commonly used second line treatment for patients with congenital hyperinsulinism. • The administration of octreotide is frequently associated with gastrointestinal adverse events., What Is New: • Our study indicates that octreotide is used without serious adverse effects to maintain blood glucose levels in infants with congenital hyperinsulinism who are otherwise in good health. • The incidence of adverse events in patients treated with octreotide is dose-dependent., Competing Interests: Declarations. The studies involving humans were approved by Children’s hospital of Fudan University (2017-130). The studies were conducted in accordance with the local legislation and institutional requirements. The participants provided their written informed consent to participate in this study. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The incidence of neuroendocrine tumors (NETs) in the US is rising, with 8.3 cases per 100,000 individuals diagnosed in 2018 compared with 6.98 cases per 100,000 individuals diagnosed in 2012. 1,2 Most patients with NETs are diagnosed with metastatic disease, at which point curative surgery is no longer a treatment option. 3 Prior to 2017, available treatments for advanced NETs included somatostatin analogues (lanreotide [Somatuline] and octreotide [Sandostatin]), targeted therapy (everolimus [Afinitor] and sunitinib [Sutent]), and chemotherapy. 4-7 In 2017, the World Health Organization added a classification for well-differentiated grade 3 NETs (Ki67 > 20% and ≤ 55%). 8 Previously these tumors were placed under the umbrella of poorly differentiated neuroendocrine carcinomas. Given that well-differentiated grade 3 NETs are relatively new, standard-of-care treatment options are undefined.

Purpose: Renal and hematological toxicity are side effects and dose-limiting factors of Peptide Receptor Radionuclide Therapy (PRRT). We aimed to assess the changes in renal and hematological function and associations with survival in neuroendocrine tumor (NET) patients treated with PRRT., Methods: A retrospective cohort of 448 NET patients treated with either 177 Lu-DOTATATE or 90 Y-DOTATOC were followed for changes of renal and hematological function. Renal function was assessed by monitoring changes in serum creatinine, blood urea nitrogen and estimated glomerular filtration rate. Hematological function was determined by examining changes in white blood cell counts (WBC), platelet counts, and hemoglobin levels over time. Piecewise linear mixed effect models were applied to model the longitudinal repeated measurements of renal and hematological function. Overall survival (OS) and progression-free survival (PFS) were modelled using Cox proportional hazard regressions., Results: Of the 448 PRRT treated patients, 335 received 177 Lu-DOTATATE (74.78%) and 113 were treated with 90 Y-DOTATOC (25.22%). Comparing patients treated with 177 Lu-DOTATATE to those treated with 90 Y-DOTATOC, renal function did not differ significantly prior to, during or after PRRT. Compared with patients treated with 90 Y-DOTATOC, significantly decreased indicators of hematological function were observed in those treated with 177 Lu-DOTATATE prior to and during PRRT treatment (WBC: estimate, -0.10, 95% CI, -0.15 to -0.05; P < 0.001; platelet count: estimate, -2.53, 95% CI, -3.83 to -1.24; P < 0.001), and no significant recovery was observed in hematological function post PRRT. Individuals who received 177 Lu-DOTATATE tended to have a longer PFS (hazard ratio, 0.47, 95%CI: 0.28-0.79, P = 0.004) compared with 90 Y-DOTATOC, but there was no difference in OS., Conclusion: There was no significant renal, but minor hematological toxicity, in patients treated with 177 Lu-DOTATATE compared with 90 Y-DOTATOC. Compared to 90 Y-DOTATOC, 177 Lu-DOTATATE appears to enhance PFS, but not OS. Treatment with 177 Lu-DOTATATE may necessitate follow-up for hematological toxicity irrespective of other therapies prior to PRRT., (© 2024. The Author(s).)

Background: With the development of endoscopic technology, the application of upper endoscopy can quickly target the lesion site of patients with peptic ulcer complicated with upper gastrointestinal bleeding., Objective: This study aims to discuss the clinical effect of octreotide combined with upper endoscopy in treating peptic ulcer complicated with upper gastrointestinal hemorrhage., Methods: A total of 82 patients diagnosed with peptic ulcer complicated with upper gastrointestinal hemorrhage were recruited as study objects in the researchers' hospital. According to the treatment method, this retrospective study divided the patients into a control group (n=41, receiving adrenaline injection under upper endoscopy only) and a treatment group (n=41, receiving adrenaline injection under upper endoscopy and Octreotide intravenously)., Results: After treatment, the volume of blood loss, average hemostasis time, hospital stay, and time of occult blood turning negative in the treatment group were shorter than those in the control group (P < .05). After treatment, the clinical efficacy of the treatment group was better than that of the control group (P < .05). The levels of prothrombin time (PT), activated partial thromboplastin time (APTT), and thrombin time (TT) levels in the treatment group were lower than those in the control group, with significant differences (P < .05)., Conclusion and Relevance: Combining octreotide and upper endoscopy has affirmative efficacy and good hemostatic effect on treating peptic ulcer complicated with upper gastrointestinal hemorrhage with less pain and short recovery time, which is worthy of clinical application.

Purpose: Small cell lung cancer (SCLC) is a highly aggressive tumor with neuroendocrine origin. Although SCLC frequently express somatostatin receptor type 2 (SSTR2), a significant clinical benefit of SSTR2-targeted radionuclide therapies of SCLC was not observed so far. We hypothesize that combination treatment with a PARP inhibitor (PARPi) could lead to radiosensitization and increase the effectiveness of SSTR2-targeted therapy in SCLC., Methods: SSTR2-ligand uptake of the SCLC cell lines H69 and H446 was evaluated in vitro using flow cytometry, and in vivo using SPECT imaging and cut-and-count biodistribution. Single-agent (Olaparib, Rucaparib, [ 177 Lu]Lu-DOTA-TOC) and combination treatment responses were determined in vitro via cell viability, clonogenic survival and γH2AX DNA damage assays. In vivo, we treated athymic nude mice bearing H69 or H446 xenografts with Olaparib, Rucaparib, or [ 177 Lu]Lu-DOTA-TOC alone or with combination treatment regimens to assess the impact on tumor growth and survival of the treated mice., Results: H446 and H69 cells exhibited low SSTR2 expression, i.e. 60 to 90% lower uptake of SSTR2-ligands compared to AR42J cells. In vitro, combination treatment of [ 177 Lu]Lu-DOTA-TOC with PARPi resulted in 2.9- to 67-fold increased potency relative to [ 177 Lu]Lu-DOTA-TOC alone. We observed decreased clonogenic survival and higher amounts of persistent DNA damage compared to single-agent treatment for both Olaparib and Rucaparib. In vivo, tumor doubling times increased to 1.6-fold (H446) and 2.2-fold (H69) under combination treatment, and 1.0 to 1.1-fold (H446) and 1.1 to 1.7-fold (H69) in monotherapies compared to untreated animals. Concurrently, median survival was higher in the combination treatment groups in both models compared to monotherapy and untreated mice. Fractionating the PRRT dose did not lead to further improvement of therapeutic outcome., Conclusion: The addition of PARPi can markedly improve the potency of SSTR2-targeted PRRT in SCLC models in SSTR2 low-expressing tumors. Further evaluation in humans seems justified based on the results as novel treatment options for SCLC are urgently needed., (© 2024. The Author(s).)

Our objective is to explore quantitative imaging markers for early prediction of treatment response in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) undergoing [ 177 Lu]Lu-DOTATATE therapy. By doing so, we aim to enable timely switching to more effective therapies in order to prevent time-resource waste and minimize toxicities. Methods: Patients diagnosed with unresectable or metastatic, progressive, well-differentiated, receptor-positive GEP-NETs who received 4 sessions of [ 177 Lu]Lu-DOTATATE were retrospectively selected. Using SPECT/CT images taken at the end of treatment sessions, we counted all visible tumors and measured their largest diameters to calculate the tumor burden score (TBS). Up to 4 target lesions were selected and semiautomatically segmented. Target lesion peak counts and spleen peak counts were measured, and normalized peak counts were calculated. Changes in TBS (ΔTBS) and changes in normalized peak count (ΔnPC) throughout treatment sessions in relation to the first treatment session were calculated. Treatment responses were evaluated using third-month CT and were binarized as progressive disease (PD) or non-PD. Results: Twenty-seven patients were included (7 PD, 20 non-PD). Significant differences were observed in ΔTBS second-first , ΔTBS third-first , and ΔTBS fourth-first (where second-first, third-first, and fourth-first denote scan number between the second and first, third and first, and fourth and first [ 177 Lu]Lu-DOTATATE treatment cycles), respectively) between the PD and non-PD groups (median, 0.043 vs. -0.049, 0.08 vs. -0.116, and 0.109 vs. -0.123 [ P = 0.023, P = 0.002, and P < 0.001], respectively). ΔnPC second-first showed significant group differences (mean, -0.107 vs. -0.282; P = 0.033); ΔnPC third-first and ΔnPC fourth-first did not reach statistical significance (mean, -0.122 vs. -0.312 and -0.183 vs. -0.405 [ P = 0.117 and 0.067], respectively). At the optimal threshold, ΔTBS fourth-first exhibited an area under the curve (AUC) of 0.957, achieving 100% sensitivity and 80% specificity. ΔTBS second-first and ΔTBS third-first reached AUCs of 0.793 and 0.893, sensitivities of 71.4%, and specificities of 85% and 95%, respectively. ΔnPC second-first , ΔnPC third-first , and ΔnPC fourth-first showed AUCs of 0.764, 0.693, and 0.679; sensitivities of 71.4%, 71.4%, and 100%; and specificities of 75%, 70%, and 35%, respectively. Conclusion: ΔTBS and ΔnPC can predict [ 177 Lu]Lu-DOTATATE response by the second treatment session., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Preclinical data have shown that 161 Tb-labeled peptides targeting the somatostatin receptor are therapeutically more effective for peptide receptor radionuclide therapy than are their 177 Lu-labeled counterparts. To further substantiate this enhanced therapeutic effect, we performed cellular dosimetry to quantify the absorbed dose to the cell nucleus and compared dose-response curves to evaluate differences in relative biological effectiveness in vitro. Methods: CA20948 cell survival was assessed after treatment with [ 161 Tb]Tb- and [ 177 Lu]Lu-DOTATATE (agonist) and with [ 161 Tb]Tb- and [ 177 Lu]Lu-DOTA-LM3 (antagonist) via a clonogenic assay. Cell binding, internalization, and dissociation assays were performed up to 7 d to acquire time-integrated activity coefficients. Separate S values for each type of particle emission (Auger/internal conversion [IC] electrons and β - particles) were computed via Monte Carlo simulations, while considering spheric cells. Once the absorbed dose to the cell nucleus was calculated, survival curves were fitted to the appropriate linear or linear-quadratic model and corresponding relative biological effectiveness was evaluated. Results: Although the radiopeptide uptake was independent of the radionuclide, [ 161 Tb]Tb-DOTATATE and [ 161 Tb]Tb-DOTA-LM3 delivered a 3.6 and 3.8 times higher dose to the nucleus, respectively, than their 177 Lu-labeled counterparts on saturated receptor binding. This increased nucleus-absorbed dose was mainly due to the additional emission of IC and not Auger electrons by 161 Tb. When activity concentrations were considered, both [ 161 Tb]Tb-DOTATATE and [ 161 Tb]Tb-DOTA-LM3 showed a lower survival fraction than did labeling with 177 Lu. When the absorbed dose to the nucleus was considered, no significant difference could be observed between the dose-response curves for [ 161 Tb]Tb- and [ 177 Lu]Lu-DOTATATE. [ 161 Tb]Tb-DOTA-LM3 showed a linear-quadratic dose response, whereas [ 161 Tb]Tb-DOTATATE showed only a linear dose response within the observed dose range, suggesting additional cell membrane damage by Auger electrons. Conclusion: The IC, rather than Auger, electrons emitted by 161 Tb resulted in a higher absorbed dose to the cell nucleus and lower clonogenic survival for [ 161 Tb]Tb-DOTATATE and [ 161 Tb]Tb-DOTA-LM3 than for the 177 Lu-labeled analogs. In contrast, [ 161 Tb]Tb-DOTATATE showed no higher dose response than [ 177 Lu]Lu-DOTATATE, whereas for [ 161 Tb]Tb-DOTA-LM3 an additional quadratic response was observed. Because of this quadratic response, potentially caused by cell membrane damage, [ 161 Tb]Tb-DOTA-LM3 is a more effective radiopeptide than [ 161 Tb]Tb-DOTATATE for labeling with 161 Tb., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Background: Postoperative pancreatic fistulas lead to substantially increased morbidity, mortality, and healthcare costs after pancreatectomy. Studies have reported conflicting data on the role of prophylactic somatostatin analogs in the reduction of postoperative pancreatic fistula. Current practice patterns, surgeon beliefs, and barriers to using these drugs in the Americas is not known., Methods: An online 26-question cross-sectional survey was distributed via email to the members of the Americas Hepato-Pancreato-Biliary Association in April 2023., Results: One hundred and two surgeons responded in spring 2023. 48.0% of respondents reported using prophylactic SSAs during their surgical training, however, only 29.4% do so in their current practice, most commonly when performing Whipple procedures. Octreotide was the most frequently used SSA (34.3%), followed by octreotide LAR (12.7%) and pasireotide (11.8%). Reasons for not prescribing included a lack of high-quality data (62.7%), perception of limited efficacy (34.3%) and high cost (30.4%)., Conclusion: These results highlight key areas for future study including understanding surgeon rationale for patient and drug selection. Variable practice patterns amongst surgeons also underscore the importance of generalizability in the design of future clinical trials in order to maximize impact., (Copyright © 2024 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Variceal hemorrhage treatment includes endoscopy within 12 hours of admission and octreotide therapy for 2-5 days post-endoscopy. Duration of pre-endoscopy octreotide can be prolonged when intervention is delayed. Objective: This study aimed to evaluate the impact of extended pre-endoscopy octreotide on rebleeding after endoscopy when comparing short vs long durations of post-endoscopy octreotide. Methods: This was a single center, retrospective cohort evaluating adult cirrhotic patients with esophageal variceal hemorrhage admitted between July 1, 2017 and June 30, 2020. Study groups included patients receiving octreotide ≥12 hours prior to endoscopy followed by ≤ 48 (short course) or >48 hours (standard course) after endoscopy. The primary outcome was post-endoscopy rebleeding, defined as hemoglobin decrease of ≥2 g/dL from baseline or the requirement of ≥1 unit of packed red blood cells. Results: Of the 169 patients included, 88 patients received short course octreotide after endoscopy, and 81 patients received standard course octreotide after endoscopy. Twenty-nine (33%) patients in the short course group and 43 (53.1%) in the standard course group experienced the primary endpoint (OR 2.3, 95% CI 1.24 - 4.29; P = .008). Conclusion: Extended pre-endoscopy octreotide may be beneficial in preventing rebleeding when intervention is delayed. Further studies are needed to determine the necessary octreotide duration in delayed endoscopy and varying bleeding risk., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: Patients with advanced, well-differentiated neuroendocrine tumors (WD-NETs) often require both peptide receptor radionuclide therapy (PRRT) and subsequent chemotherapy. However, no mid-PRRT predictors are available to identify patients who will not benefit from subsequent PRRT to limit their radiation exposure. Our aim is to characterize patients for whom subsequent PRRT is less efficacious on the basis of mid-PRRT evaluation., Materials and Methods: A retrospective study of patients with WD-NET who underwent ≥four PRRT cycles. Data gathered included demographics, tumor grade, stage, and response (partial response [PR], stable disease [SD], and progressive disease [PD]) on the basis of RECIST 1.1 criteria and 68 Ga-dotatate positron emission tomography-computerized tomography pretreatment, after second and fourth treatment cycle, 6 months after fourth cycle, and at last follow-up., Results: Fifty-one patients (51.6% women; age at diagnosis 66.0 ± 1.65 years), with pancreatic NET (PNET; n = 24), small intestine NET (n = 13), or other NET (n = 14), received PRRT, resulting in PR (n = 21), SD (n = 23), and PD (n = 3). Of the patients reaching PR after PRRT, most reached PR after two treatments (70.4%), with only 11.8% PR occurring between subsequent cycles ( P = .001). Furthermore, patients with PR at mid-treatment had higher PR rates after PRRT completion than those with SD ( P = .007). Patients harboring PNET who achieved PR had a more pronounced reduction of tumor burden in additional cycles than patients who did not (25.6% v 1.5%; P = .03, respectively). On the multivariable model, adjusted for grade and primary site, PR at mid-treatment evaluation was associated with a 20.9 adjusted odds ratio for additional PR at PRRT completion ( P = .002)., Conclusion: Mid-PRRT assessment predicts subsequent PRRT response in patients with WD-NET, especially those with PNET, informing personalized management and consideration of reduced bone marrow radiation exposure in high-risk patients.

Purpose: Well-differentiated neuroendocrine neoplasms (NETs) overexpress the somatostatin receptor, which is the target for the peptide receptor radionuclide therapy (PRRT). NETs have a slow growth rate and can metastasize to liver, bone, and lungs. In NETs patients, liver metastasis is an important prognostic marker because liver failure is one of the most common causes of death in this population. In this regard, we aimed to describe the changes in laboratorial parameters in patients submitted to PRRT with 177 Lu-DOTATATE, focusing on hepatic parameters., Patients and Methods: One hundred ten patients treated with 1 to 4 cycles of 7.4 GBq (200 mCi) of 177 Lu-DOTATATE from January 2011 to December 2021 were analyzed in this retrospective observational single-center study. Patients were submitted to blood tests before and after each cycle of PRRT. Laboratory measurements were collected to assess liver function, cholestasis, kidney, and bone marrow function., Results: In the general population (n = 110), ALP ( P = 0.013) and GGT ( P < 0.001) showed a statistically significant reduction. Patients with high liver disease volume showed a statistically significant reduction in ALT ( P = 0.016), whereas patients with low liver disease volume showed a statistically significant reduction in GGT ( P = 0.013). All parameters for bone marrow function showed a statistically significant decrease in all population subsets., Conclusions: Patients treated with 177 Lu-DOTATATE showed a significant improvement in liver function and cholestasis parameters, and a consistent decrease in bone marrow function, even in the presence of advanced liver disease., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

The aim of the present study was to evaluate the safety and efficacy of radionuclide therapy with [ 177 Lu]Lu-DOTA-TATE according to our single center experience at the University of Naples Federico II. For the present analysis, we considered 21 patients with progressive, advanced, well-differentiated G1 and G2 in patients with gastro-entero-pancreatic (GEP) neuroendocrine tumors (NETs) treated with [ 177 Lu]Lu-DOTA-TATE according to the decisions of a multidisciplinary team. All patients underwent four cycles of 7-8 GBq of [ 177 Lu]Lu-DOTA-TATE every 8 weeks. A whole-body scan (WBS) was performed 4, 48, and 168 h after each treatment. The dosimetry towards the organ at risk and target lesions was calculated. For each patient, renal and bone marrow parameters were evaluated before, during, and 3 months after the end of the treatment. Follow-up data were obtained and RECIST criteria were considered as the endpoint. Among 21 patients enrolled (mean age 65 ± 9 years); 17 (81%) were men and the small intestine was the most frequent location of disease (n = 12). A mild albeit significant variation ( p < 0.05) in both platelets and white blood cell counts among all time points was observed, despite it disappearing 3 months after the end of the therapy. According to the RECIST criteria, 11 (55%) patients had a partial response to therapy and 8 (40%) had stable disease. Only one (5%) patient had disease progression 4 months after treatment. Our data confirm that [ 177 Lu]Lu-DOTA is safe and effective in controlling the burden disease of G1/G2 GEP-NETs patients.

Proper collimator selection is critical to obtaining high-quality, interpretable nuclear medicine images. Collimators help eliminate scatter, which leads to poor spatial resolution and blurry images. We present the case of a posttherapy 177 Lu-DOTATATE (Lutathera) patient who was initially imaged with a low-energy, high-resolution collimator routinely used in 99m Tc imaging. On image review, the patient was reimaged with the appropriate medium-energy, high-resolution collimator, which resulted in improved image quality. When reviewing the quality of images, it is important to understand modifications to the imaging that can significantly improve image quality and interpretation., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

177 Lu-DOTATATE is an effective second-line treatment for metastatic or nonresectable neuroendocrine tumors. This treatment can result in hematologic severe adverse reactions (SARs). Preemptive identification of patients at risk of SARs could mitigate this risk and improve treatment safety and outcomes. Methods: Demographic and oncologic history, pretreatment laboratory values, and SAR frequency were obtained for 126 sequential patients treated with 177 Lu-DOTATATE. Univariable and multivariable logistic regression models identified factors correlating with SARs. Results: Relative pretreatment anemia, leukopenia, thrombocytopenia, and elevated mean corpuscular volume (MCV) were significantly correlated with SARs, with an odds ratio of 16 (95% CI, 5-65) in patients with an MCV greater than 95 fL. Conclusion: Pretreatment bone marrow dyscrasias, including an MCV greater than 95 fL, may predict patients at risk for SARs when treated with 177 Lu-DOTATATE. Further study is needed to determine whether the risks of SARs outweigh the benefit in these patients., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Everolimus and peptide receptor radionuclide therapy (PRRT, 177 Lu-DOTATATE) are 2 treatments recommended in guidelines for gastroenteropancreatic metastatic neuroendocrine tumors. However, the best treatment sequence remains unknown. Methods: We designed a retrospective multicenter study that included patients from the national prospective database of the Groupe d'Étude des Tumeurs Endocrines who had been treated using everolimus and PRRT between April 2004 and October 2022. The primary aim was to compare the 2 treatments (everolimus and PRRT) in terms of efficacy and safety, and the secondary aim was to evaluate the sequences (PRRT followed by everolimus or everolimus followed by PRRT) based on overall progression-free survival (PFS) (PFS during first treatment + PFS during second treatment) in patients with metastatic neuroendocrine tumors. Results: Both treatments were used for 84 patients. The objective response rate and median PFS were 5 (6.0%) and 16.1 mo (95% CI, 11.5-20.7 mo), respectively, under everolimus and 19 (22.6%) and 24.5 mo (95% CI, 17.7-31.3 mo), respectively, for PRRT. The safety profile was also better for PRRT. Median overall PFS was 43.2 mo (95% CI, 33.7-52.7 mo) for the everolimus-PRRT sequence and 30.6 mo (95% CI, 17.8-43.4 mo) for the PRRT-everolimus sequence (hazard ratio, 0.69; 95% CI, 0.39-1.24; P = 0.22). Conclusion: PRRT was more effective and less toxic than everolimus. Overall PFS was similar between the 2 sequences, suggesting case-by-case discussion if the patient is eligible for both treatments, but PRRT should be used first when an objective response is needed or in frail populations., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Recurrence of meningiomas after surgery and radiotherapy deserves specific attention because of the lack of active third-line therapies. Somatostatin receptors are usually overexpressed on the cell membrane of meningiomas, and this has led the way to a radionuclide theranostic approach. Diagnoses with 68 Ga-DOTA-octreotide and peptide receptor radionuclide therapy (PRRT) with 90 Y/ 177 Lu-DOTA-octreotide are currently possible options within experimental protocols or as compassionate use in small patient groups. Methods: From October 2009 to October 2021, 42 meningioma patients with radiologic recurrence after standard therapies were treated with 90 Y-DOTATOC (dosage of 1.1 or 5.5 GBq) or with 177 Lu-DOTATATE (dosage of 3.7 or 5.5 GBq) in a mean of 4 cycles. All patients showed intense uptake at diagnostic 68 Ga-DOTATOC PET/CT or in an 111 In-octreotide scan. Results: Of 42 patients treated, 5 patients received 90 Y-DOTATOC with a cumulative activity of 11.1 GBq and 37 patients received 177 Lu-DOTATATE with a cumulative activity of 22 GBq. The disease control rate was 57%. With a median follow-up of 63 mo, median progression-free survival was 16 mo, and median overall survival was 36 mo. Retreatment 177 Lu-PRRT was performed in 6 patients with an administered median activity of 13 GBq in a mean of 5 cycles. With a 75.8-mo follow-up, median progression-free survival and overall survival were 6.5 and 17 mo, respectively. Only 1 patient discontinued the treatment because of grade 3 platelet toxicity. A rapidly transient grade 2 neutropenia was recorded in 1 retreated patient. Conclusion: PRRT in patients with advanced meningiomas overexpressing somatostatin receptor 2 was active and well tolerated, showing a 57% disease control rate. Furthermore, PRRT could represent a potential retreatment option. Further studies, also in combination with other treatments, are warranted., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Purpose: Somatostatin receptor (SSTR) imaging features are predictive of treatment outcome for neuroendocrine tumor (NET) patients receiving peptide receptor radionuclide therapy (PRRT). However, comprehensive (all metastatic lesions), longitudinal (temporal variation), and lesion-level measured features have never been explored. Such features allow for capturing the heterogeneity in disease response to treatment. Furthermore, models combining these features are lacking. In this work we evaluated the predictive power of comprehensive, longitudinal, lesion-level 68 GA-SSTR-PET features combined with a multivariate linear regression (MLR) model., Methods: This retrospective study enrolled NET patients treated with [ 177 Lu]Lu-DOTA-TATE and imaged with [ 68 Ga]Ga-DOTA-TATE at baseline and post-therapy. All lesions were segmented, anatomically labeled, and longitudinally matched. Lesion-level uptake and variation in uptake were measured. Patient-level features were engineered and selected for modeling of progression-free survival (PFS). The model was validated via concordance index, patient classification (ROC analysis), and survival analysis (Kaplan-Meier and Cox proportional hazards). The MLR was benchmarked against single feature predictions., Results: Thirty-six NET patients were enrolled and stratified into poor and good responders (PFS ≥ 25 months). Four patient-level features were selected, the MLR concordance index was 0.826, and the AUC was 0.88 (0.85 specificity, 0.81 sensitivity). Survival analysis led to significant patient stratification (p<.001) and hazard ratio (3⨯10 -5 ). Lastly, in a benchmark study, the MLR modeling approach outperformed all the single feature predictors., Conclusion: Comprehensive, lesion-level, longitudinal 68 GA-SSTR-PET analysis, combined with MLR modeling, leads to excellent predictions of PRRT outcome in NET patients, outperforming non-comprehensive, patient-level, and single time-point feature predictions., Message: Neuroendocrine tumor, peptide receptor radionuclide therapy, Somatostatin Receptor Imaging, Outcome Prediction, Treatment Response Assessment., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: This study aimed to develop a user-friendly prediction formula for dose rate adjustment after initial 177 Lu-Dotatate therapy from a prospective observational study of patients., Materials and Methods: This study included consenting patients in a prospective observational study who underwent their first treatment in four cycles of 177 Lu-Dotatate treatment at our hospital between January 2022 and February 2024. All patients received 7.4 GBq of 177 Lu-Dotatate. The prediction formula was derived from the regression analysis of tumor-related factors and renal function. Creatinine clearance was estimated using the Cockcroft-Gault equation in this study for renal function., Results: Among the 13 patients (seven males, six females, median age: 59 years), logarithmically transformed total tumor volume (cc) and maximum tumor diameter (mm) of primary tumors or metastases showed strong correlations (p < 0.001, R 2  = 0.897). As such, the maximum tumor diameter was used as the tumor parameter in the prediction formula. Additionally, maximum tumor diameter and creatinine clearance showed strong (p < 0.001, R 2  = 0.768) and moderate (p = 0.013, R 2  = 445) correlations, respectively, with the ratio of the dose rate 5.5-h post-administration to the dose rate immediately post-administration (%) at 1 m from the body surface. The resulting formula, 51.4 + 0.360 × maximum tumor diameter (mm) - 0.212 × creatinine clearance (ml/min), demonstrated an extremely strong correlation (p < 0.001, R 2  = 0.937)., Conclusion: The present study showed that the maximum tumor diameter and renal function affected the declining the dose rate of patients surface after 177 Lu-Dotatate, which can inform post-administration dose rate management and potentially facilitate outpatient treatment in Japan., (© 2024. The Author(s).)

Purpose: Gastroenteropancreatic -neuroendocrine tumours (GEP-NETs) are commonly treated with surgical resection or long-term therapies for tumour growth control. Lutetium [ 177 Lu]-DOTA-TATE was approved for the treatment of GEP-NETs after the phase III NETTER 1trial demonstrated improved progression free survival, objective response rates and health-related quality of life (HRQoL) compared to high-dose somatostatin analogues. No real-world data exist on prescribing habits and clinically significant endpoints for [ 177 Lu]Lu-DOTA-TATE treatment in Italy. REAL-LU is a multicentre, long-term observational study in patients with unresectable/metastatic GEP-NETs progressing on standard therapies in Italian clinical practice. A pre-specified interim analysis was performed at the end of the enrolment period, data from which are described herein., Methods: Overall duration of REAL-LU will be approximately 48 months, with 12- and 36-month recruitment and follow-up periods, respectively. The primary objective is to evaluate [ 177 Lu]Lu-DOTA-TATE effectiveness in terms of progression-free survival. Secondary objectives include safety, impact on HRQoL, and identification of prognostic factors. This pre-specified interim analysis describes patient profiles, at the end of enrollment, of those prescribed [ 177 Lu]Lu-DOTA-TATE for GEP-NETs in Italy., Results: Among 161 evaluable patients, mean age was 64.7 ± 10.3 years at study entry, 83.8% presented with no clinical signs of disease at physical examination, and most had minor disease symptoms. All patients had metastatic disease, most commonly in the liver (83.9%) with a median of two metastatic sites. In 90.7% of patients, the disease was stage IV, and 68.3% had ≥ 1 target lesion. [ 177 Lu]Lu-DOTA-TATE was prescribed mainly as second-line therapy (61.6%) and following surgery (58.4%). HRQoL assessments revealed high levels of functioning and low levels of symptoms at baseline; 50.0% of patients were symptom-free at study entry., Conclusion: The characteristics of patients who received [177Lu]Lu-DOTA-TATE in Italy are similar to those of the GEP-NET population of NETTER 1 with trial but with a higher proportion of patients with a grade 2 (71%). With regard to the tumor grade profile, our study cohort appears to be closer to that of NETTER-2 study population which included patients with G2 or G3 advanced GEP-NETs (i.e. Ki-67 ≥ 10% and ≤ 55%). Further analysis of effectiveness and safety can be anticipated as REAL-LU data mature., Study Registration: ClinicalTrials.gov, NCT04727723; Study Registration Date: 25 January, 2021; https://clinicaltrials.gov/study/NCT04727723?cond=NCT04727723&rank=1., (© 2024. The Author(s).)

Abstract: A 76-year-old woman with liver and bone metastasis of a duodenal neuroendocrine tumor received peptide receptor radionuclide therapy with 177 Lu-DOTATATE. Scintigraphy with SPECT/CT performed 4 days after the treatment demonstrated 177 Lu-DOTATATE uptake as multifocal ground glass opacities in the bilateral lungs. This uptake was considered to be due to COVID-19 pneumonia because the patient was infected with the virus 7 days prior to the treatment. The lung opacities became smaller, showing a decreased uptake, 2 months later, after the second treatment. 177 Lu-DOTATATE may be taken up during the active phase of COVID-19 pneumonia., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: The aim of this study was to assess the association among toxicity, dosimetry of organs-at-risk, and disease progression in patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs) treated with 177 Lu-DOTATATE., Patients and Methods: Thirty-seven patients with GEP-NETs underwent 177 Lu-DOTATATE peptide receptor radionuclide therapy (PRRT) in a single-arm, prospective, phase 2 study, where patients were followed up with blood tests, isotopic glomerular filtration rate (iGFR), and imaging examinations (CT/MRI and PET) every 6 months until disease progression. Adverse events (AEs) graded per CTCAEv4.03 and occurring during treatment were collected and followed up until resolution. Dosimetry, including biologically effective doses (BEDs) to kidneys, BED to bone marrow, and absorbed dose (AD) to spleen, was performed after each PRRT cycle. Statistical analyses explored associations among dosimetry, toxicity, and patient progression free-survival., Results: The most common AEs were anemia and lymphopenia (65%), followed by thrombocytopenia and fatigue (each 51%), alopecia (46%), and nausea (41%). The most common grade ≥3 AE was lymphopenia (43%). There was no grade ≥3 nephrotoxicity. The median iGFR % decrease was 11% ( P < 0.001), at a median follow-up of 23 months. iGFR %decrease and renal BED did not correlate (Spearman ρ = -0.09). Similarly, no significant association was found between bone marrow BED or spleen AD and the grades of hematological toxicities. We observed no association between progression free-survival and either the decline of renal function or the occurrence of hematological toxicities during PRRT., Conclusions: This study confirms the safety profile of 177 Lu-DOTATATE PRRT in patients with GEP-NETs irrespective of the dosimetry of organs at risk. Kidney, bone marrow, and spleen dosimetry measures were not associated with renal or hematological toxicity., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: In a prior, retrospective study, 76% of patients with advanced neuroendocrine tumors undergoing 177 Lu-DOTATOC molecular radiotherapy (MRT) showed their best response within 8 months from the first MRT cycle. In 24% of patients, latency was much greater up to >22 months after the first cycle, and long after near-complete decay of 177 Lu from the last cycle. An immune response induced by MRT seems a likely explanation. As a crude measure of immunocompetence, the authors investigated whether blood cell counts (BCCs) may have predictive value for MRT outcome with 177 Lu-DOTATOC. Methods: 56 Patients with neuroendocrine tumors (NET) were administered 177 Lu-DOTATOC (mean 2.1 cycles; range 1-4) with median radioactivity of 7.0 GBq/cycle at 3-month intervals. Patients' BCCs were evaluated for four responder categories: CR, PR, SD, and PD (RECIST 1.1). Furthermore, baseline BCCs were correlated with progression-free survival (PFS). Finally, BCCs of patients with (PMT + ) and without prior medical therapy (PMT - ) were compared. Results: Significant differences between responder categories were found for baseline hemoglobin (Hb), erythrocytes, neutrophils, lymphocytes, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), and LEHN-score, integrating lymphocyte, erythrocyte, and neutrophil counts, and Hb level, but not for leukocytes and platelets. LEHN-score yielded an almost complete separation between CR and PD groups. In analogy, PFS times showed significant correlations with baseline Hb, erythrocytes, neutrophils, lymphocytes, NLR, PLR, and LEHN-score, the LEHN-score showing the strongest correlation, but not with leukocytes and platelets. For PMT - patients, median PFS was 34.5 months, compared with 20.8 months in PMT + patients, with corresponding baseline lymphocyte (32.1 ± 9.6% vs. 24.5 ± 11.6%, p = 0.028) and neutrophil (54.9 ± 11.6% vs. 63.5 ± 13.7%, p = 0.039) counts. Conclusion: These findings emphasize the significance of an immune response to MRT for obtaining optimal therapy efficacy and support concepts to enhance the immune response of less immunocompetent patients before MRT. It seems advisable to avoid prior or concomitant immunosuppressant medical therapy.

Introduction: The available data for the safety and efficacy of repeat peptide receptor radionuclide therapy (PRRT) are almost exclusively from European centers. We present an updated experience with repeat PRRT in a cohort of US patients with neuroendocrine tumors (NETs) at our NET center of excellence., Methods: We used our single-center longitudinal NET registry to identify patients who had been previously treated with at least one dose of PRRT (PRRT 1, either 177 Lu DOTATATE or 90 Y DOTATOC) and following radiographic disease progression were re-treated with a second course of PRRT (PRRT 2). We reviewed patient, tumor and treatment characteristics, objective response rates, and toxicities after PRRT 1 and PRRT 2., Results: A total of 11 patients were included in the analysis. 45.5% (5/11) of patients received 177 Lu DOTATATE PRRT only, both for PRRT1 and PRRT 2, while 54.5% (6/11) of patients received 90 Y DOTATOC PRRT for PRRT1. At first restaging scan after PRRT2 (3-6 months), 18.2% (2/11), 36.4% (4/11), and 27.3% (3/11) of patients had PR, SD, and PD, respectively; 2/11 patients (18.2%) died before the first restaging scan. Therefore, 5/11 (45.5%) patients were noted to have disease progression. Median PFS for PRRT1 was 25.4 months and median PFS for PRRT2 was 13.1 months (p = 0.0001). We did not find a statistically significant difference between the occurrence of short and long-term hematological toxicities as well as renal toxicity after PRRT1 and PRRT2., Conclusion: We show that repeat PRRT may benefit select patients and have an acceptable safety profile. In our cohort, PFS was significantly lower after PRRT2 as compared to PRRT1., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Growth hormone (GH) is a crucial regulator of growth, cell reproduction, and regeneration; and it is controlled by growth hormone-releasing hormone (GHRH) and somatostatin. Lipopolysaccharides (LPS) can compromise endothelial function, leading to increased inflammation and vascular leak. Octreotide (OCT) is an FDA-approved synthetic somatostatin analog (SSA) used to treat acromegaly and neuroendocrine tumors. The present study investigates the effects of OCT on LPS-induced injury in bovine and human lung endothelial cells, as well as in mouse lungs. Our in vitro observations suggest that OCT effectively counteracts LPS-induced endothelial leak, inflammation, and reactive oxygen species (ROS) generation. Furthermore, OCT reduces bronchoalveolar lavage fluid (BALF) protein concentration in an experimental model of Acute Lung Injury (ALI). Our study suggests that OCT mitigates LPS-induced endothelial cell and lung injury, suggesting that it may represent an exciting therapeutic possibility in diseases related to barrier dysfunction., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

[ 75 Se]tauroselcholic acid (SeHCAT) retention measurement provides a noninvasive test for bile acid diarrhea (BAD); however, it is sensitive to the presence of other radionuclides. Two SeHCAT patients at the Royal Free Hospital (RFH) had significant discrepancies between the lower photopeak (111-159 keV) and central photopeak (242-296 keV) windows, indicating contamination with a radionuclide other than 75 Selenium. These patients had received lutetium-177 oxodotreotide ( 177 Lu-DOTATATE) therapy 98 and 151 days before their SeHCAT tests. Traces of 177 Lu may be retained longer than typically modeled, along with the contaminant 177m Lu. This work includes a retrospective audit to examine the prevalence of SeHCAT tests being affected by 177 Lu and phantom measurements to investigate the potential impact. Of 579 patients who received 177 Lu-DOTATATE therapy at our center, 11 subsequently attended for a SeHCAT test. The two previously identified patients may have had compromised SeHCAT results; however, the other patients had longer intervals between their therapy and test, and their tests are believed to be valid. Spectra were acquired from a phantom containing either a SeHCAT capsule or a mixture of 177 Lu/ 177m Lu representative of a patient >90 days after their treatment. The SeHCAT spectrum was scaled to produce simulated day-7 spectra, and the SeHCAT retention that would have been calculated if 177 Lu/ 177m Lu were present was determined. All SeHCAT measurement windows are affected by the 177 Lu/ 177m Lu, producing clinically significant errors. Patients requiring SeHCAT testing should be asked whether they have ever received 177 Lu-DOTATATE. Patient-specific background measurements may be useful for checking for significant levels of other radionuclides., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Resection of non-functioning pancreatic neuroendocrine tumours (NF-PanNETs) is curative in most patients. The potential benefits of neoadjuvant treatments have, however, never been explored. The primary aim of this study was to evaluate the safety of neoadjuvant 177Lu-labelled DOTA0-octreotate (177Lu-DOTATATE) followed by surgery in patients with NF-PanNETs., Methods: NEOLUPANET was a multicentre, single-arm, phase II trial of patients with sporadic, resectable or potentially resectable NF-PanNETs at high-risk of recurrence; those with positive 68Ga-labelled DOTA PET were eligible. All patients were candidates for neoadjuvant 177Lu-DOTATATE followed by surgery. A sample size of 30 patients was calculated to test postoperative complication rates against predefined cut-offs. The primary endpoint was safety, reflected by postoperative morbidity and mortality within 90 days. Secondary endpoints included rate of objective radiological response and quality of life., Results: From March 2020 to February 2023, 31 patients were enrolled, of whom 26 completed 4 cycles of 177Lu-DOTATATE. A partial radiological response was observed in 18 of 31 patients, and 13 patients had stable disease. Disease progression was not observed. Twenty-four R0 resections and 4 R1 resections were performed in 29 patients who underwent surgery. One tumour was unresectable owing to vascular involvement. There was no postoperative death. Postoperative complications occurred in 21 of 29 patients. Severe complications were observed in seven patients. Quality of life remained stable after 177Lu-DOTATATE and decreased after surgery., Conclusion: Neoadjuvant treatment with 177Lu-DOTATATE is safe and effective for patients with NF-PanNETs., (© The Author(s) 2024. Published by Oxford University Press on behalf of BJS Foundation Ltd.)

Objective: We investigated metabolic tumor volume (MTV) and total lesion glycolysis (TLG) on pre-treatment FDG-PET as prognostic markers for survival in patients with metastatic neuroendocrine neoplasms (NENs) receiving peptide receptor radionuclide therapy (PRRT)., Methods: A retrospective review of patients with metastatic NENs receiving PRRT was undertaken. Pre-treatment FDG-PET images were analyzed and variables collected included MTV and TLG (dichotomized by median into high vs low). Main Outcomes were overall survival (OS) and progression-free survival (PFS) by MTV and TLG (high vs low)., Results: One hundred five patients were included. Median age was 64 years (50% male). Main primary NEN sites were small bowel (43.8%) and pancreas (40.0%). Median MTV was 3.8 mL and median TLG was 19.9. Dichotomization formed identical cohorts regardless of whether MTV or TLG were used. Median OS was 72 months; OS did not differ based on MTV/TLG high versus low (47.4 months vs not reached; hazard ratio, 0.43; 95% confidence interval [CI], 0.18-1.04; P = 0.0594). Median PFS was 30.4 months; PFS differed based on MTV/TLG high versus low (21.6 months vs 45.7 months; hazard ratio, 0.35; 95% CI, 0.19-0.64; P = 0.007)., Conclusions: Low MTV/TLG on pre-treatment FDG-PET was associated with longer PFS in metastatic NEN patients receiving PRRT., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Pharmacological prevention of postoperative pancreatic fistula (POPF) after pancreatectomy is open to debate. The present study compares clinically significant POPF rates in patients randomized between somatostatin versus octreotide as prophylactic treatment., Methods: Multicentric randomized controlled open study in patient's candidate for pancreaticoduodenectomy (PD) or distal pancreatectomy (DP) comparing somatostatin continuous intravenous infusion for 7 days versus octreotid 100 μg, every 8 hours subcutaneous injection for 7 days, stratified by procedure (PD vs DP) and size of the main pancreatic duct (>4 mm) on grade B/C POPF rates at 90 days based on an intention-to-treat analysis., Results: Of 763 eligible patients, 651 were randomized: 327 in the octreotide arm and 324 in the somatostatin arm, with comparable the stratification criteria - type of surgery and main pancreatic duct dilatation. Most patients had PD (n=480; 73.8%), on soft/normal pancreas (n=367; 63.2%) with a nondilated main pancreatic duct (n=472; 72.5%), most often for pancreatic adenocarcinoma (n=311; 47.8%). Almost all patients had abdominal drainage (n=621; 96.1%) and 121 (19.5%) left the hospital with the drain in place (median length of stay=16 days). A total of 153 patients (23.5%) developed a grade B/C POPF with no difference between both groups: 24.1%: somatostatin arm and 22.9%: octreotide arm (χ 2 test, P =0.73, ITT analysis). Absence of statistically significant difference persisted after adjustment for stratification variables and in per-protocol analysis., Conclusion: Continuous intravenous somatostatin is not statistically different from subcutaneous octreotide in the prevention of grade B/C POPF after pancreatectomy., Findings: In the PREFIPS Randomized Clinical Trial including 651 patients, a total of 153 patients (23.5%) developed a grade B/C POPF with no significant difference between both groups: 24.1%: somatostatin arm and 22.9%: octreotide arm (χ 2 test, P =0.73, ITT analysis). Absence of statistically significant difference persisted after adjustment for stratification variables and in per-protocol analysis., Competing Interests: S.G. reported grants, personal fees, and nonfinancial support fomr IPSEN, Mylan, Mayoli, Novartis. The remaining authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

177 Lu-DOTATATE therapy is an effective treatment for advanced neuroendocrine tumors, despite its dose-limiting hematotoxicity. Herein, the significance of off-target splenic irradiation is unknown. Our study aims to identify predictive markers of peptide receptor radionuclide therapy-induced leukopenia. Methods: We retrospectively analyzed blood counts and imaging data of 88 patients with histologically confirmed, unresectable metastatic neuroendocrine tumors who received 177 Lu-DOTATATE treatment at our institution from February 2009 to July 2021. Inclusion criterium was a tumor uptake equivalent to or greater than that in the liver on baseline receptor imaging. We excluded patients with less than 24 mo of follow-up and those patients who received fewer than 4 treatment cycles, additional therapies, or blood transfusions during follow-up. Results: Our study revealed absolute and relative white blood cell counts and relative spleen volume reduction as independent predictors of radiation-induced leukopenia at 24 mo. However, a 30% decline in spleen volume 12 mo after treatment most accurately predicted patients proceeding to leukopenia at 24 mo (receiver operating characteristic area under the curve of 0.91, sensitivity of 0.93, and specificity of 0.90), outperforming all other parameters by far. Conclusion: Automated splenic volume assessments demonstrated superior predictive capabilities for the development of leukopenia in patients undergoing 177 Lu-DOTATATE treatment compared with conventional laboratory parameters. The reduction in spleen size proves to be a valuable, routinely available, and quantitative imaging-based biomarker for predicting radiation-induced leukopenia. This suggests potential clinical applications for risk assessment and management., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Abstract: We report the cases of 4 patients treated for recurrent meningiomas of various grades. Pretreatment 68 Ga-DOTATOC PET/CT was performed prior to screening for vectorized internal radiotherapy with 177 Lu-DOTATATE or prior external radiotherapy to aid contouring. None of these patients had sufficient uptake to be eligible for 177 Lu-DOTATATE or reliable contouring. Most recurrences were grades II and III, suggesting a loss of physiological somatostatin receptor overexpression in these tumors. Therefore, the benefit of treatment with 177 Lu-DOTATATE in the current indication is questionable. In the absence of a validated systemic treatment, and considering a few case reports, treatment with 177 Lu-PSMA could be investigated as an additional vectorized internal radiotherapy option., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Introduction: Acromegaly is a rare endocrine disorder usually caused by a benign growth hormone‒secreting pituitary adenoma. Surgical adenoma resection is typically the first line of treatment, and medical therapy is used for patients with persistent disease following surgery, for adenoma recurrence, or for patients ineligible for, or declining, surgery. Approved somatostatin receptor ligands (SRLs) have been limited to injectable options, until recently. Oral octreotide capsules (OOC) are the first approved oral SRL for patients with acromegaly., Areas Covered: We review published reports and provide case study examples demonstrating practical considerations on the use of OOC. Using two hypothetical case scenarios, we discuss current treatment patterns, breakthrough symptoms and quality of life (QoL), efficacy of SRLs, OOC dose titration, evaluation of OOC treatment response, and incidence and management of adverse events., Expert Opinion: OOC are an option for patients with acromegaly including those who experience breakthrough symptoms, who have preference for oral therapies, or other reasons for declining injectable SRLs. OOC have been associated with improved patient-reported QoL measures compared with those reported for lanreotide and octreotide. Continued real-world experience will determine whether OOC, alone or in combination with other therapies, provides further advantages over current injectable acromegaly treatments.

Peptide receptor radionuclide therapy presents the possibility of tracing and quantifying the uptake of the drug in the body and performing dosimetry, potentially allowing individualization of treatment schemes. However, the details of how neuroendocrine tumors (NETs) respond to different absorbed doses are insufficiently known. Here, we investigated the relationship between tumor-absorbed dose and tumor response in a cohort of patients with NETs treated with [ 177 Lu]Lu-DOTATATE. Methods: This was a retrospective study based on 69 tumors in 32 patients treated within a clinical trial. Dosimetry was performed at each cycle of [ 177 Lu]Lu-DOTATATE, rendering 366 individual absorbed dose assessments. Hybrid planar-SPECT/CT imaging using [ 177 Lu]Lu-DOTATATE was used, including quantitative SPECT reconstruction, voxel-based absorbed dose rate calculation, semiautomatic image segmentation, and partial-volume correction. Changes in tumor volume were used to determine tumor response. The volume for each tumor was manually delineated on consecutive CT scans, giving a total of 712 individual tumor volume assessments. Tumors were stratified according to grade. The relationship between absorbed dose and response was investigated using mixed-effects models and logistic regression. Tumors smaller than 4 cm 3 were excluded. Results: In grade 2 NETs, a clear relationship between absorbed dose and volume reduction was observed. Our observations suggest a 90% probability of partial tumor response for an accumulated tumor-absorbed dose of at least 135 Gy. Conclusion: Our findings are in accordance with previous observations regarding the relationship between tumor shrinkage and absorbed dose. Moreover, our data suggest an absorbed dose threshold for partial response in grade 2 NETs. These observations provide valuable insights for the design of dosimetry-guided peptide receptor radionuclide therapy schemes., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Acromegaly is a rare disease caused by a growth hormone excess, usually due to a secreting pituitary adenoma. Somatostatin receptor ligands (SRL) are the mainstay of medical therapy for patients with acromegaly who fail to achieve biochemical control post-operatively or are not eligible for surgical treatment. SRLs are typically administered as monthly injections and have shown to be effective in maintaining biochemical and radiological control of acromegaly. However, these injections may cause local adverse events and are associated with increased psychological burden in some patients. Oral octreotide provides a new alternative for patients responding to injectable SRLs. This new formulation has shown to have similar safety and efficacy profiles compared to injectable SRLs and may be a preferable option for some patients with acromegaly. The aim of this review is to provide an overview of the role of oral octreotide in the management of acromegaly., Competing Interests: Declaration of Competing Interest Lisa B. Nachtigall has received grant support from Recordati and Amryt and has served as a consultant for Crinetics., (Copyright © 2024. Published by Elsevier Ltd.)

Abstract: This case report explores the use of 177 Lu-DOTATATE in a hemodialysis patient. For the first time, this study assesses the average dose received by the bone marrow, the primary organ at risk, using an original double estimation method through independently acquired imaging and biological samples counting data. Despite elevated doses, the absorbed doses to the bone marrow (0.662-0.740 Gy) were within safe limits. Radiation protection measurements for staff were also compliant. This work supports that effective early dialysis and systematic personalized dosimetry are crucial for hemodialysis patients undergoing 177 Lu-PRRT due to their variability (residual excretion, treatment history, etc)., Competing Interests: Conflicts of interest and sources of funding: none declared. Conflicts of interest and sources of funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Purpose: This single-center retrospective study explores the safety and efficacy of 177 Lu-DOTATATE in children and young adult population with metastatic/inoperable neuroendocrine tumors (NETs)., Patients and Methods: This study is a retrospective analysis of all children and young adult patients (≤29 years) with advanced inoperable/metastatic epithelial or nonepithelial NETs who were administered a median of 4 cycles of 177 Lu-DOTATATE therapy and low-dose oral capecitabine as a radiosensitizer every 8-12 weeks, except 2 patients who received CAPTEM chemotherapy. The radiological response was assessed using RECIST 1.1 on interim and end-of-treatment 68 Ga-DOTANOC PET/CT. The primary endpoint was objective response rate, whereas disease control rate, toxicity profile, progression-free survival, and overall survival were secondary endpoints., Results: Nineteen biopsy-proven NET patients (median age, 22 ± 10 years) with 8 of them adolescents (10-18 years) and the remaining young adults (19-29 years) were included. Fourteen patients had gastroenteropancreatic neuroendocrine tumor (pancreas being most common primary site), whereas the rest had non-gastroenteropancreatic neuroendocrine tumor. A total of 65 cycles of 177 Lu-DOTATATE (range, 1-6 cycles) were administered with a median cumulative activity of 600 mCi (range, 100-1000 mCi). The objective response rate and disease control rate were 41% and 94%, respectively. Grade 1 and 2 adverse events were observed in 14 (74%) and 5 (26%) of 19 patients, respectively. In a total of 8 events (42%), 4 events each of disease progression and death occurred during a median follow-up of 80.1 months with an estimated 5-year progression-free survival and overall survival of 54% (95% confidence interval, 30-78) and 63% (95% confidence interval, 39-87), respectively., Conclusions: 177 Lu-DOTATATE appears safe and effective in children and young adults with metastatic/inoperable NETs. Large prospective trials are required to validate these results., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: There are currently no standard first-line treatment options for patients with higher grade 2-3, well-differentiated, advanced, gastroenteropancreatic neuroendocrine tumours. We aimed to investigate the efficacy and safety of first-line [ 177 Lu]Lu-DOTA-TATE ( 177 Lu-Dotatate) treatment., Methods: NETTER-2 was an open-label, randomised, parallel-group, superiority, phase 3 trial. We enrolled patients (aged ≥15 years) with newly diagnosed higher grade 2 (Ki67 ≥10% and ≤20%) and grade 3 (Ki67 >20% and ≤55%), somatostatin receptor-positive (in all target lesions), advanced gastroenteropancreatic neuroendocrine tumours from 45 centres across nine countries in North America, Europe, and Asia. We used interactive response technologies to randomly assign (2:1) patients to receive four cycles (cycle interval was 8 weeks ± 1 week) of intravenous 177 Lu-Dotatate plus intramuscular octreotide 30 mg long-acting repeatable (LAR) then octreotide 30 mg LAR every 4 weeks ( 177 Lu-Dotatate group) or high-dose octreotide 60 mg LAR every 4 weeks (control group), stratified by neuroendocrine tumour grade (2 vs 3) and origin (pancreas vs other). Tumour assessments were done at baseline, week 16, and week 24, and then every 12 weeks until disease progression or death. The primary endpoint was progression-free survival by blinded, independent, central radiology assessment. We did the primary analysis at 101 progression-free survival events as the final progression-free survival analysis. NETTER-2 is registered with ClinicalTrials.gov, NCT03972488, and is active and not recruiting., Findings: Between Jan 22, 2020, and Oct 13, 2022, we screened 261 patients, 35 (13%) of whom were excluded. We randomly assigned 226 (87%) patients (121 [54%] male and 105 [46%] female) to the 177 Lu-Dotatate group (n=151 [67%]) and control group (n=75 [33%]). Median progression-free survival was 8·5 months (95% CI 7·7-13·8) in the control group and 22·8 months (19·4-not estimated) in the 177 Lu-Dotatate group (stratified hazard ratio 0·276 [0·182-0·418]; p<0·0001). During the treatment period, adverse events (of any grade) occurred in 136 (93%) of 147 treated patients in the 177 Lu-Dotatate group and 69 (95%) of 73 treated patients in the control group. There were no study drug-related deaths during the treatment period., Interpretation: First-line 177 Lu-Dotatate plus octreotide LAR significantly extended median progression-free survival (by 14 months) in patients with grade 2 or 3 advanced gastroenteropancreatic neuroendocrine tumours. 177 Lu-Dotatate should be considered a new standard of care in first-line therapy in this population., Funding: Advanced Accelerator Applications, a Novartis Company., Competing Interests: Declaration of interests SS reports support for the present work from Novartis; grants or contracts from Novartis; consulting fees from Ipsen, Novartis, and Camurus; and meeting attendance support from Ipsen and Novartis. DH reports support for the present work from Novartis; grants or contracts from Novartis, ITM, RayzeBio, Thermo Fisher Scientific, Camurus, and Genentech/Roche; consulting fees from Novartis, TerSera, ITM, Crinetics, Amryt, Camurus, Chimeric Therapeutics, Harpoon Therapeutics, HarbourBioMed, Lantheus, Exelixis, and Ipsen; and participation on a data safety monitoring board for Alphamedix. SM reports advisory board participation for Novartis Oncology and Ipsen. KH reports payment for steering committee participation from Novartis; grants or contracts from Novartis and SOFIE Biosciences; consulting fees from Advanced Accelerator Applications (a Novartis company), Amgen, AstraZeneca, Bain Capital, Bayer, Boston Scientific, Convergent, Curium, Debiopharm, EcoR1, Fusion, GE Healthcare, Immedica, ITM, Janssen, Merck, Molecular Partners, NVision, Pfizer, POINT Biopharma, Radiopharm Theranostics, Rhine Pharma, Siemens Healthineers, SOFIE Biosciences, Telix, Theragnostics, and Y-mAbs; honoraria from PeerVoice; meeting support from Janssen; advisory board participation for Fusion and GE Healthcare; and stock or stock options for SOFIE Biosciences, Pharma15, NVision, Convergent, Aktis Oncology, and AdvanCell. MP reports grants or contracts from Advanced Accelerator Applications (a Novartis company), Novartis, Ipsen, ITM, Camurus, and Boehringer Ingelheim; consulting fees from Advanced Accelerator Applications (a Novartis company), Novartis, Ipsen, Riemser, and HUTCHMED; honoraria from Ipsen, Advanced Accelerator Applications (a Novartis company), Novartis, Boehringer Ingelheim, MSD, Lilly, Recordati, Sanofi, and Serb; advisory board participation for Crinetics and Advanced Accelerator Applications (a Novartis company); and unpaid roles as ENETS committee member and President, on the ESMO education committee, and on the INCA advisory board. PLK reports grants or contracts from RayzeBio and Novartis; honoraria from Natera, ITM, BMS, and Foundation Medicine; steering committee participation (uncompensated) for RayzeBio and Exelixis; and advisory board participation and honoraria from Amgen, Genentech, Crinetics, HUTCHMED, and Ipsen. BC reports advisory board participation and honoraria from Advanced Accelerator Applications (a Novartis company). SL reports advisory board participation for Advanced Accelerator Applications (a Novartis company). JC reports grants or contracts from Novartis, Pfizer, AstraZeneca, Advanced Accelerator Applications (a Novartis company), Eisai, Amgen, and Bayer; and consulting fees and honoraria from Novartis, Pfizer, Ipsen, Exelixis, Bayer, Eisai, Advanced Accelerator Applications (a Novartis company), Amgen, Sanofi, Lilly, Hutchinson Pharma, ITM, Advanz, Merck, Esteve, and Roche. AG-B reports consulting fees from Advanced Accelerator Applications (a Novartis company), Bayer, and Sanofi; and speaker fees and meeting support from Novartis. D-YO reports grants or contracts from AstraZeneca, Novartis, Array, Eli Lilly, Servier, BeiGene, MSD, and Handok; and advisory board participation for AstraZeneca, Novartis, Genentech/Roche, Merck, Bayer, Taiho, ASLAN, Halozyme, Zymeworks, BMS/Celgene, BeiGene, Basilea, Turning Point, Yuhan, Arcus Biosciences, IQVIA, MSD, LG Chem, Astellas, AbbVie, J-Pharma, Mirati Therapeutics, Eutilex, Moderna, and Idience. CY reports grants or contracts from Bayer, Ipsen, AstraZeneca, Boehringer Ingelheim, Servier, and Eisai; and honoraria from Bayer, Ipsen, MSD, Merck, Celgene, AstraZeneca, GSK, Eisai, Roche, Genentech, and Novartis. TRH reports consulting fees from TerSera; advisory board participation and research support from Camurus, ITM, Advanced Accelerator Applications (a Novartis company), Crinetics, and Perspective Therapeutics; research support from Thermo Fisher Scientific; and an unpaid role as President of NANETS. IF, YZ, and PA report employment by Novartis and stock or stock options for Novartis. WWdH reports consulting fees and honoraria from Ipsen, Novartis, and Advanced Accelerator Applications (a Novartis company); and consulting fees from ITM. DF reports grants or contracts from Camurus and Pfizer; honoraria from Novartis and Recordati Rare Diseases; and advisory board participation for Camurus, Ipsen, Novartis, Recordati Rare Diseases, and Pfizer. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved, including those for text and data mining, AI training, and similar technologies.)

Background and Objectives : High-grade malignant neuroendocrine tumors (G3 NETs) and neuroendocrine carcinomas (NECs) are characterized by rapid proliferation, high metastatic capacity, and strong expression of somatostatin receptors (SSTRs). We aimed to analyze the presence of SSTRs in NET G3 and NEC, and to correlate their expression with the use of octreotide and pasireotide. Materials and Methods : For this purpose, we first performed a retrospective study of G3 NET and NEC patients, which included the determination of SSTR expression and response to octreotide treatment. Second, we selected the H69 small cell lung cancer cell line to determine the effect of octreotide and pasireotide. Results : Our results showed the traditional somatostatin analog (SSA) octreotide was ineffective in patients with NET G3 and NEC. On the other hand, RT-qPCR showed a high expression of SSTR2 and SSTR5 in H69 cells. Interestingly, while octreotide did not modify H69 cell proliferation, a strong inhibition of proliferation was detected with the use of pasireotide. Conclusions : In view of these results, a clinical trial in NET G3 and NEC patients using pasireotide is necessary to determine the usefulness of this drug in improving patient treatment., Competing Interests: The authors declare no conflicts of interest.

Purpose: This study aims to elucidate the role of quantitative SSTR-PET metrics and clinicopathological biomarkers in the progression-free survival (PFS) and overall survival (OS) of neuroendocrine tumors (NETs) treated with peptide receptor radionuclide therapy (PRRT). Methods: A retrospective analysis including 91 NET patients (M47/F44; age 66 years, range 34-90 years) who completed four cycles of standard 177 Lu-DOTATATE was conducted. SSTR-avid tumors were segmented from pretherapy SSTR-PET images using a semiautomatic workflow with the tumors labeled based on the anatomical regions. Multiple image-based features including total and organ-specific tumor volume and SSTR density along with clinicopathological biomarkers including Ki-67, chromogranin A (CgA) and alkaline phosphatase (ALP) were analyzed with respect to the PRRT response. Results: The median OS was 39.4 months (95% CI: 33.1-NA months), while the median PFS was 23.9 months (95% CI: 19.3-32.4 months). Total SSTR-avid tumor volume (HR = 3.6; P = 0.07) and bone tumor volume (HR = 1.5; P = 0.003) were associated with shorter OS. Also, total tumor volume (HR = 4.3; P = 0.01), liver tumor volume (HR = 1.8; P = 0.05) and bone tumor volume (HR = 1.4; P = 0.01) were associated with shorter PFS. Furthermore, the presence of large lesion volume with low SSTR uptake was correlated with worse OS (HR = 1.4; P = 0.03) and PFS (HR = 1.5; P = 0.003). Among the biomarkers, elevated baseline CgA and ALP showed a negative association with both OS (CgA: HR = 4.9; P = 0.003, ALP: HR = 52.6; P = 0.004) and PFS (CgA: HR = 4.2; P = 0.002, ALP: HR = 9.4; P = 0.06). Similarly, number of prior systemic treatments was associated with shorter OS (HR = 1.4; P = 0.003) and PFS (HR = 1.2; P = 0.05). Additionally, tumors originating from the midgut primary site demonstrated longer PFS, compared to the pancreas (HR = 1.6; P = 0.16), and those categorized as unknown primary (HR = 3.0; P = 0.002). Conclusion: Image-based features such as SSTR-avid tumor volume, bone tumor involvement, and the presence of large tumors with low SSTR expression demonstrated significant predictive value for PFS, suggesting potential clinical utility in NETs management. Moreover, elevated CgA and ALP, along with an increased number of prior systemic treatments, emerged as significant factors associated with worse PRRT outcomes., Competing Interests: Competing Interests: Yuni Dewaraja is a consultant for MIM Software. The other authors have declared that no competing interest exists., (© The author(s).)

Para -aminohippurate, also known as p -aminohippuric acid (PAH), is used clinically to measure effective renal plasma flow. Preclinically, it was shown to reduce 177 Lu-DOTATOC uptake in the kidneys while improving bioavailability compared with amino acid (AA) coinfusion. We report the safety and efficacy of PAH coinfusion during peptide receptor radiotherapy in patients with neuroendocrine tumors. Methods: Twelve patients with metastatic or unresectable gastroenteropancreatic neuroendocrine tumors received 177 Lu-DOTATOC in 33 treatment cycles. Either 8 g of PAH or a mixture of 25 g of arginine and 25 g of lysine were coinfused. Safety was assessed by monitoring laboratory data, including hematologic and renal data, as well as electrolytes obtained before and 24 h after treatment. For radiation dosimetry, whole-body scans were performed at 1, 24, and 48 h and a SPECT/CT scan was performed at 48 h, along with blood sampling at 5 min and 0.5, 2, 4, 24, and 48 h after administration. Absorbed dose estimations for the kidneys and bone marrow were performed according to the MIRD concept. Results: In 15 treatment cycles, PAH was coinfused. No changes in mean creatinine level, glomerular filtration rate, and serum electrolytes were observed before or 24 h after treatment when using PAH protection ( P ≥ 0.20), whereas serum chloride and serum phosphate increased significantly under AA (both P < 0.01). Kidney-absorbed dose coefficients were 0.60 ± 0.14 Gy/GBq with PAH and 0.53 ± 0.16 Gy/GBq with AA. Based on extrapolated cumulative kidney-absorbed doses for 4 cycles, 1 patient with PAH protection and 1 patient with AA protection in our patient group would exceed the 23-Gy conservative threshold. The bone marrow-absorbed dose coefficient was 0.012 ± 0.004 Gy/GBq with PAH and 0.012 ± 0.003 Gy/GBq with AA. Conclusion: PAH is a promising alternative to AA for renal protection during peptide receptor radiotherapy. Further research is required to systematically investigate the safety profile and radiation dosimetry at varying PAH plasma concentrations., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

[ 177 Lu]Lu-DOTATATE has been approved for progressive and inoperable gastroenteropancreatic neuroendocrine tumors (GEP-NETs) that overexpress somatostatin receptors. The absorbed doses by limiting organs and tumors can be quantified by serial postinfusion scintigraphy measurements of the γ-emissions from 177 Lu. The objective of this work was to explore how postinfusion [ 177 Lu]Lu-DOTATATE dosimetry could influence clinical management by predicting treatment efficacy (tumor shrinkage and survival) and toxicity. Methods: Patients with GEP-NETs treated with [ 177 Lu]Lu-DOTATATE between 2016 and 2022 and who underwent dosimetry were included. Absorbed doses were calculated for healthy organs (liver, kidneys, bone marrow, and spleen) and tumors using PLANET Dose and the local energy deposition method based on serial posttreatment SPECT/CT. Up to 5 lesions per site were selected and measured on images collected at baseline and 3 mo after treatment end (measurement masked to the somatostatin receptor imaging uptake). For toxicity assessment, laboratory parameters were regularly monitored. Clinical data, including time to death or progression, were collected from the patients' health records. Correlations between absorbed doses by organs and toxicity and between absorbed doses by lesions and tumor volume variation were studied using regression models. Results: In total, 35 dosimetric studies were performed in patients with mostly grade 2 (77%) tumors and metastases in liver (89%), lymph nodes (77%), and bone (34%), and 146 lesions were analyzed: 1-9 lesions per patient, mostly liver metastases (65%) and lymph nodes (25%). The median total absorbed dose by tumors was 94.4 Gy. The absorbed doses by tumors significantly decreased between cycles. The absorbed dose by tumors was significantly associated with tumor volume variation ( P < 0.001) 3 mo after treatment end, and it was a significant prognostic factor for survival. Toxicity analysis showed a correlation between the decrease of hematologic parameters such as lymphocytes or platelet concentrations and the absorbed doses by the spleen or bone marrow. The mean absorbed dose by the kidneys was not correlated with nephrotoxicity during the studied period. Conclusion: In patients treated with [ 177 Lu]Lu-DOTATATE for GEP-NETs, tumor and healthy organ dosimetry can predict survival and toxicities, thus influencing clinical management., (© 2024 by the Society of Nuclear Medicine and Molecular Imaging.)

Source Citation: Goltstein LC, Grooteman KV, Bernts LH, et al. Standard of care versus octreotide in angiodysplasia-related bleeding (the OCEAN study): a multicenter randomized controlled trial. Gastroenterology. 2024;166:690-703. 38158089., Competing Interests: Disclosures: Disclosure forms are available with the article online.

Purpose: We aimed to evaluate the efficacy and safety of 225 Ac-DOTATATE targeted α therapy (TAT) in various neuroendocrine neoplasms (NENs) with high somatostatin receptor (SSTR) expression., Patients and Methods: This single-center prospective study included 10 patients with histologically diagnosed NENs that exhibited increased SSTR expression on 68 Ga-DOTATATE PET/CT imaging. All patients received 225 Ac-DOTATATE TAT. The primary end points were molecular imaging-based response and disease control rate (DCR), measured using the slightly modified Positron Emission Tomography Response Criteria in Solid Tumors 1.0. The secondary end points were adverse event profiles and clinical responses. The adverse event profile was determined according to the Common Terminology Criteria for Adverse Events version 5.0. Clinical response was assessed using the EORTC QLQ-C30 v3.0 (European Organization for Research and Treatment of Cancer Core Quality of Life questionnaire version 3.0)., Results: A molecular imaging-based partial response was observed in 40% of all patients, SD in 40%, PD in 20%, and DCR in 80%. The DCR was 83.3% (5/6) in patients who were previously treated with 177 Lu-DOTATATE. According to the EORTC QLQ-C30 v3.0 score, most symptoms improved after 225 Ac-DOTATATE treatment, with only diarrhea showing no improvement. Grade III/IV hematological, kidney, and liver toxicities were not observed. The median follow-up time was 14 months (7-22 months), and no deaths were reported., Conclusions: This initial study suggests that 225 Ac-DOTATATE is a potentially promising option for treating NENs with elevated SSTR expression, with an acceptable toxicity profile and well-tolerated adverse effects., Competing Interests: Conflicts of interest and sources of funding: The authors declare that they have no conflict of interest. This study was supported in part by research foundation projects from Luzhou Science and Technology Department (20107) and (2022-JYJ-118), and The Affiliated Hospital of Southwest Medical University (20087)., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

The use of octreotide in managing intrathoracic chyle leak following esophagectomy has gained popularity in the adult population. While the benefits of octreotide have been confirmed in the pediatric population, there remains limited evidence to support its use in the adults post-esophagectomy. Thus, we performed a single-institution cohort study to characterize its efficacy. The study was performed using a prospective, single-center database, from which clinicopathologic characteristics were extracted of patients who had post-esophagectomy chyle leaks. Kaplan-Meier and multivariable Cox regression analyses were performed to investigate the effect of octreotide use on chest tube duration (CTD), hospital length of stay (LOS), and overall survival (OS). In our cohort, 74 patients met inclusion criteria, among whom 27 (36.5%) received octreotide. Kaplan-Meier revealed no significant effect of octreotide on CTD (P = 0.890), LOS (P = 0.740), or OS (P = 0.570). Multivariable Cox regression analyses further corroborated that octreotide had no effect on CTD (HR = 0.62, 95% confidence interval [CI]: 0.32-1.20, P = 0.155), LOS (HR = 0.64, CI: 0.34-1.21, P = 0.168), or OS (1.08, CI: 0.53-2.19, P = 0.833). Octreotide use in adult patients with chyle leak following esophagectomy lacks evidence of association with meaningful clinical outcomes. Level 1 evidence is needed prior to further consideration in this population., (© The Author(s) 2024. Published by Oxford University Press on behalf of International Society for Diseases of the Esophagus. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Abstract: Peptide receptor radionuclide therapy (PRRT) has shown to be effective and safe in metastatic gastroenteropancreatic and nongastroenteropancreatic neuroendocrine tumors. However, the selection criteria for PRRT are restricted to patients with good performance status (Eastern Cooperative Oncology Group score ≤2 or Karnofsky performance score ≥60). This denies many patients with adequate somatostatin receptor expression and biochemical profiles from the beneficial effects of PRRT on the quality of life, daily function, and overall survival. The 2 cases highlight the favorable response of PRRT in patients with metastatic neuroendocrine tumor having a very poor performance status initially., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)