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Aim Of the Study: Skeletal muscle metastases (SMM) are a rare entity, mainly detected at autopsy. Nevertheless, radiological and nuclear medicine imaging can contribute to the diagnosis with a significant impact on the treatment and prognosis of neoplastic patients. This study aimed to systematically review the features of SMM at imaging considering the primary tumors and the sites of occurrence.Materials and Methods: We conducted a systematic search of three electronic database (i.e., PubMed, Science Direct, and Web of Science) up to May 2019, without any language or time interval restriction. Two reviewers performed the search and selection process, data extraction, and synthesis. We resolved disagreements by consensus and/or involving a third reviewer. The included studies have been classified according to the Oxford Centre for Evidence Based Medicine (CEBM) grading system.Results: Out of 8598 and 1077 articles respectively for radiological and hybrid imaging, 29 papers were included. According to CEBM, twelve were level 4. Computed tomography (CT) is mainly applied and, despite the existence of CT and magnetic resonance-based classifications, these are rarely used. Positron emission tomography/CT allowed the detection of small and subtle lesion also in the extremities. Muscles of the trunk were mostly affected and mainly respiratory tumors are associated with this type of metastatic spread.Conclusion: Radiological and hybrid imaging allow a precise characterization of SMM. However, a more systematic approach, including also the application of available classification systems, may increase the diagnostic accuracy for this rare type of metastases.Key Points: • Skeletal muscle metastases have heterogeneous characteristics at imaging but mostly abscess-like features and high metabolic activity are described. • Skeletal muscle metastases mainly affect the muscles of the trunk. • Pulmonary, urological, and gastrointestinal cancers are the most frequent cause of skeletal muscle metastases. [ABSTRACT FROM AUTHOR]

Objectives: To clarify differences in incidences of articular and extra-articular involvement in patients with polymyalgia rheumatica (PMR) using FDG-PET/CT. Methods: Twenty PMR patients were enrolled in this retrospective study. We compared frequency, degree, and patterns (diffuse or non-diffuse) of abnormal FDG accumulation in the proximal and distal articular structures (PAS, DAS), and extra-articular synovial structures (ESS). Regional analyses were performed for the large joints (shoulder, hip, and knee). Results: The incidences of positive FDG accumulation were significantly higher in the PAS (96.7%) and ESS (91.4%) than in the DAS (31.8%, p<.0001), although, the incidence in the knees (96.2%) was exceptionally high. PAS (2.79 ± 0.61) and ESS (2.52 ± 0.85) had significantly higher visual scores than DAS (0.89 ± 1.33, p<.0001). Shoulder, hip, and knee joints each had a different accumulation pattern. Strong FDG accumulation was frequently observed in the medial-to-subscapular part of the shoulder joints, the lateral part of the hip joints, and the medial part of the knee joints. Conclusion: ESS were found to be the main affected areas in PMR patients as well as PAS. DAS involvement occurred with low frequency except in the knee joints. Each large joint showed a different accumulation pattern and its own characteristically strongly affected areas. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) are two primary liver cancers. Synchronous occurrence of both types is rare. Here, we present a case of synchronous, double primary liver cancer in a patient who underwent successful surgical resection. A 77-year-old woman presented with two suspected liver tumors. Dynamic computed tomography (CT) and ethoxybenzyl-magnetic resonance imaging revealed two lesions, one in hepatic segments S8/4 and another in S5. Positron emission tomography (PET)/CT scans revealed an elevated maximum standardized uptake value (SUVmax) of 5.7 in the S8/4 tumor, and no elevation in the S5 tumor. The S8/4 tumor was diagnosed as either ICC or mixed-type liver cancer, while the S5 tumor was confirmed HCC. Surgical resection confirmed the diagnosis, while pathology identified the S8/4 tumor as ICC and the S5 tumor as HCC. Two months post-operation, the patient received adjuvant chemotherapy and completed eight courses with no recurrence one year later. Synchronous double-primary HCC and ICC is uncommon and exhibits diagnostic and therapeutic challenges. Notably, PET-CT scans can differentiate between the two cancers, with HCC typically showing similar uptake to the background liver tissue, whereas ICC is often found with higher accumulation. This highlights the potential utility of PET/CT in preoperative diagnoses and the potential benefit of postoperative adjuvant chemotherapy in patients with double primary HCC and ICC. We report a successful case of synchronous double primary liver cancer, emphasizing the potential role of PET/CT in preoperative differentiation, and the efficacy of postoperative adjuvant chemotherapy. • Synchronous double primary liver cancers (dpHCC-ICC) are uncommon. • Preoperative diagnosis of synchronous dpHCC-ICC is challenging. • PET-CT imaging along with other modalities might help for correct diagnosis. • ICC is prognostic in patients with synchronous dpHCC-ICC. • Postoperative adjuvant chemotherapy may be effective for synchronous dpHCC-ICC. [ABSTRACT FROM AUTHOR]

We report a case of a patient performing a positron emission tomography–computed tomography (PET-CT) scan with [18F]F-Choline for biochemical relapse (Prostate specific antigen (PSA) 1.2 ng/ml) of prostate cancer. Two large areas of focal uptake with a cold core within the liver were observed. A contrast-enhanced ultrasound scan performed after the PET scan characterized these lesions as cavernous hepatic hemangiomas, and therefore, a biopsy was not performed; 3 years of follow-up and PET and MRI finding stability confirmed the benignity of their nature. [ABSTRACT FROM AUTHOR]

While extranodal involvement of diffuse large B-cell lymphoma (DLBCL) is common, skeletal muscle involvement is extremely rare. Isolated skeletal muscle involvement in lymphoma is even rarer. We present here the case of a 26-year-old woman, who was diagnosed to have a solitary isolated skeletal muscle relapse of DLBCL on surveillance 18F-fluorodeoxyglucose positron emission tomography-computed tomography, after completing first-line treatment, that was subsequently confirmed with biopsy. [ABSTRACT FROM AUTHOR]

Myeloid sarcoma (MS) is an unusual neoplasm whose understanding is principally based on the case reports and/or theoretically dated contributions. MS represents the proliferation of myeloblasts of acute myeloid leukemia (AML) at extramedullary sites. While extramedullary involvement in AML is unusual in itself, isolated (de novo) MSs that is MSs devoid of any bone marrow involvement are exceptionally rare. The present case report study expands the gamut of our acquaintance showing that MS can occur de novo, with no apparent sign or symptom of concomitant hematological disease and may show a significant response to treatment this may be omitted here. This case reports described a middle-aged male presenting as with dysphagia with isolated MS in the stomach, a very rare site.

Abstract Background Colonic metastasis from breast carcinoma is very rare. Here, we report a case of colonic metastasis from breast carcinoma. Case presentation The patient was a 51-year-old woman. She had upper abdominal pain, vomiting, and diarrhea, repeatedly. We performed abdominal contrast-enhanced computed tomography (CT) to investigate these symptoms. The CT scan revealed a tumor in the ascending colon with contrast enhancement and showed an expanded small intestine. For further investigation of this tumor, we performed whole positron emission tomography-computed tomography (PET-CT). The PET-CT scan revealed fluorodeoxyglucose uptake in the ascending colon, mesentery, left breast, and left axillary region. Analysis of biopsy samples obtained during colonoscopy revealed signet ring cell-like carcinoma. Moreover, biopsy of the breast tumor revealed invasive lobular carcinoma. Therefore, the preoperative diagnosis was colonic metastasis from breast carcinoma. Open ileocecal resection was performed. The final diagnosis was multiple metastatic breast carcinomas, and the TNM classification was T2N1M1 Stage IV. Conclusions We presented a rare case of colonic metastasis from breast carcinoma. PET-CT may be useful in the diagnosis of metastatic breast cancer. When analysis of biopsy samples obtained during colonoscopy reveals signet ring cell-like carcinoma, the possibility of breast cancer as the primary tumor should be considered.

Abstract Background Positron emission tomography–computed tomography (PET-CT) carotid standardised uptake values (SUV) of 18F-fluorodeoxyglucose (18FDG) have been proposed as an inflammatory biomarker for determining cerebrovascular diseases such as stroke. Consideration of varying methodological approaches and software packages is critical to the calculation of accurate SUVs in cross-sectional and longitudinal patient studies. The aim of this study was to investigate whether or not carotid atherosclerotic plaque SUVs are consistent and reproducible between software packages. 18FDG-PET SUVs of carotids were taken in 101 patients using two different software packages. Quality assurance checks were performed to standardise techniques before commencing the analysis where data from five to seven anatomical sites were measured. A total of ten regions of interest were drawn on each site analysed. Statistical analyses were then performed to compare SUV measurements from the two software packages and to explore reproducibility of measurements. Lastly, the time taken to complete each analysis was measured and compared. Results Statistically significant differences in SUV measurements, between the two software packages, ranging from 9 to 21.8% were found depending on ROI location. In 79% (n = 23) of the ROI locations, the differences between the SUV measurements from each software package were found to be statistically significant. The time taken to perform the analyses and export data from the software packages also varied considerably. Conclusions This study highlights the importance of standardising all aspects of methodological approaches to ensure accuracy and reproducibility. Physicians must be aware that when a PET-CT data set is analysed, subsequent follow-ups must be verified, if possible, with the same software package or cross-calibration between packages should be performed.

Objectives: This study compared the diagnostic ability of image-based parameters with texture parameters in the differentiation of hepatocellular carcinoma (HCC) and hepatic lymphoma (HL) by positron emission tomography–computed tomography (PET/CT).Methods: Patients with pathological diagnosis of HCC and HL were included in this study. Image-based and texture parameters were obtained by manual drawing of region of interest. Receiver operating characteristic (ROC) was used to test the diagnostic capacity of each parameter. Binary logistic regression was used to transform the most discriminative image-based parameters, texture parameters, and the combination of these parameters into three regression models. ROC was used to test the diagnostic capacity of these models.Result: Ninety-nine patients diagnosed with HCC (n = 76) and HL (n = 23, 10 primary HL, 13 secondary HL) by histological examination were included in this study (From 2011 to 2018, West China hospital). According to the AUC and p-value, 2 image-based parameters and five texture parameters were selected. The diagnostic ability of texture-based model was better than that of image-based model, and after combination of those two groups of parameters the diagnostic capacity improved.Conclusion: Texture parameters can differentiate HCC from HL quantitatively and improve the diagnostic ability of image-based parameters.

Purpose: Incidental gallbladder carcinoma (IGBC) is diagnosed in post-cholecystectomy specimens for benign indications, where the role of 2-fluro-2-deoxyglucose positron emission tomography/computed tomography(FDG-PET/CT) is not clearly defined. The present study aimed to assess the benefits of staging and prognosticating with FDG-PET/CT in IGBC., Materials and Methods: A retrospective observational study from a tertiary-care center from January 2010 to July 2020 was performed. The demographic, clinical, histopathological, and treatment-related histories were collected. FDG-PET/CT-image findings were compared with survival outcomes through telephonic follow-up. The chi-square test was used for comparing frequencies. The univariate and multivariate survival estimates were analyzed using the Kaplan-Meier analysis and the Cox-proportional hazard model, respectively. Log-rank test was used to compare the Kaplan-Meier curves., Results: The study included 280 postcholecystectomy participants (mean age: 52 ± 11 years; women: 227) of whom 52.1% had open surgery(146/280). Residual disease in the gallbladder fossa (54.8% vs. 36.6%, p  = 0.002) and liver infiltration (32.9% vs. 22.4%, p  = 0.05) were seen more frequently in open surgery compared to laparoscopic surgery, while anterior abdominal wall deposits were more common in laparoscopy(35.1% vs. 24%, p  = 0.041). FDG-PET/CT changed the management in 10% ( n  = 28) of patients compared to contrast-enhanced CT. The median survival was 14 months (95%CI-10.3-17.7). A higher stage of the disease on the FDG-PET/CT (loco-regional disease-HR 4.86, p  = 0.006; metastatic disease-HR 7.53, p  < 0.001) and the presence of liver infiltration (HR-1.92, p  = 0.003) were independent predictors of poor survival outcomes., Conclusion: FDG-PET/CT detects residual and metastatic disease in patients with IGBC, enabling the institution of appropriate management and acting as a tool for prognostication of survival., Competing Interests: Competing InterestsVenkata Subramanian Krishnaraju, Rajender Kumar, Bhagwant Rai Mittal, Harjeet Singh, Piyush Aggarwal, Harmandeep Singh, Thakur Deen Yadav, Ritambhra Nada, Vikas Gupta, and Rajesh Gupta declare that they have no competing interest., (© The Author(s), under exclusive licence to Korean Society of Nuclear Medicine 2024. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

Aim: To explore the role of positron emission tomography-computed tomography (PET-CT) examination in the diagnosis and treatment of ocular adnexal mucosa associated lymphoid tissue lymphoma (OAML)., Methods: The general clinical data, postoperative PET-CT results, treatment regimens, and the prognosis of 21 histopathologically confirmed OAML patients between October 2017 and September 2021 were collected. Among the 21 patients, five patients underwent surgical treatment alone, 13 patients underwent surgical treatment combined with radiotherapy, and three patients underwent surgical treatment combined with chemotherapy., Results: The follow-up period ranged from 8 to 79mo, with four cases of recurrence and no deaths. Through PET-CT examination, two patients exhibited both local ocular metabolic elevation and systemic metastasis, and one of these patients had cervical lymph node metastasis, while the other had submandibular and parotid gland metastasis. Nine patients showed only local ocular metabolic elevation, while 10 patients had no abnormal metabolic activity locally., Conclusion: PET-CT examination plays a crucial role in detecting residual lesions and recurrence following tumor resection, aiding in precise disease staging, and facilitating the development of personalized treatment plans, ultimately improving patient prognosis., Competing Interests: Conflicts of Interest: Zhang X, None; Guo QH, None; Liu R, None; Li J, None; Li YC, None; Ma JM, None., (International Journal of Ophthalmology Press.)

Sarcomatoid carcinoma, a rare and aggressive subtype of bladder cancer, accounting for 0.3% of cases, is more aggressive than urothelial carcinomas. Accurate diagnosis, crucial for treatment, can be challenging. We present a characterized case of sarcomatoid carcinoma of the urinary bladder using multimodal imaging and pathology., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Authors. Clinical Case Reports published by John Wiley & Sons Ltd.)

Introduction: The goal of this study is to compare the prognostic performance of NETPET scores, based on gallium-68 DOTANOC ( 68 Ga-DOTANOC) and fluorine-18 fluorodeoxyglucose ( 18 F-FDG) Positron Emission Tomography-Computed Tomography (PET-CT), and PET-CT metabolic parameters in metastatic gastrointestinal neuroendocrine tumors (GI-NET), while constructing and validating a nomogram derived from dual-scan PET-CT., Methods: In this retrospective study, G1-G3 GI-NET patients who underwent 68 Ga-DOTANOC and 18 F-FDG PET scans were enrolled and divided into training and internal validation cohorts. Three grading systems were constructed based on NETPET scores and standardized uptake value maximum (SUVmax). LASSO regression selected variables for a multivariable Cox model, and nomograms predicting progression-free survival (PFS) and overall survival (OS) were created. The prognostic performance of these systems was assessed using time-dependent receiver-operating characteristic (ROC) curves, concordance index (C-index), and other methods. Nomogram evaluation involved calibration curves, decision curve analysis (DCA), and the aforementioned methods in both cohorts., Results: In this study, 223 patients (130 males; mean age ±  SD: 52.6 ± 12 years) were divided into training (148) and internal validation (75) cohorts. Dual scans were classified based on NETPET scores (D1-D3). Single 68 Ga-DOTANOC and 18 F-FDG PET-CT scans were stratified into S1-S3 and F1-F3 based on SUVmax. The NETPET score-based grading system demonstrated the best OS and PFS prediction (C-index, 0.763 vs. 0.727 vs. 0.566). Nomograms for OS and PFS exhibited superior prognostic performance in both cohorts (all AUCs > 0.8)., Conclusions: New classification based on NETPET score predicts patient OS/PFS best. PET-CT-based nomograms show accurate OS/PFS forecasts.

The metastatic lesions to pancreas are reported in various malignancies. However, pancreatic metastasis from breast cancer is rare and difficult to diagnose due to nonspecific symptoms and imaging findings. At the time of diagnosis, there may already be an associated widespread metastasis. In this case report, a woman in her forties with a history of breast cancer was found to have widespread metastases, including in the pancreas. The patient was treated with chemotherapy and hormonal therapy., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Indian Journal of Nuclear Medicine.)

Objective: Uptake of the imaging tracers [ 18 F]AlF-NOTA-FAPI-04 and [ 18 F]FDG varies in some inflammatory lesions, which may result in false-positive findings for malignancy on PET/CT. Our aim was to compare the [ 18 F]AlF-NOTA-FAPI-04 and [ 18 F]FDG PET/CT imaging features of malignant and various inflammatory lung lesions and to analyze their value for differential diagnosis., Methods: We retrospectively analyzed [ 18 F]AlF-NOTA-FAPI-04 PET/CT scans from 67 cancer patients taken between December 2020 and January 2022, as well as the scans of 32 patients who also underwent [ 18 F]FDG PET/CT imaging. The maximum and mean standardized uptake values (SUVmax and SUVmean, respectively) and lesion-to-background ratio (LBR) were calculated. The predictive capabilities of semiquantitative PET/CT parameters were analyzed by receiver operating characteristic curve analysis., Results: A total of 70 inflammatory and 37 malignant lung lesions were evaluated by [ 18 F]AlF‑NOTA‑FAPI‑04 PET/CT, and 33 inflammatory and 26 malignant lung lesions also were evaluated by [ 18 F]FDG PET/CT. Inflammatory lesions exhibited lower [ 18 F]AlF-NOTA-FAPI-04 and [ 18 F]FDG uptake compared to malignant lesions, with statistically significant differences in SUVmax, SUVmean, and LBR (all p < 0.001). [ 18 F]AlF-NOTA-FAPI-04 uptake also varied among different types of inflammatory lesions (SUVmax, p = 0.005; SUVmean, p = 0.008; LBR, p < 0.001), with the highest uptake observed in bronchiectasis with infection, followed by postobstructive pneumonia, and the lowest in pneumonia. [ 18 F]FDG uptake was higher in postobstructive pneumonia than in pneumonia (SUVmax, p = 0.009; SUVmean, p = 0.016; LBR, p = 0.004)., Conclusion: [ 18 F]AlF-NOTA-FAPI-04/[ 18 F]FDG PET/CT showed significantly lower uptake in inflammatory lesions than malignancies as well as variation in different types of inflammatory lesions, and thus, may be valuable for distinguishing malignant and various inflammatory findings., Clinical Relevance Statement: Our study confirmed that the uptake of [ 18 F]AlF-NOTA-FAPI-04/[ 18 F]FDG PET/CT in inflammatory and malignant lung lesions is different, which is beneficial to distinguish inflammatory and malignant lung lesions in clinic., Key Points: • Malignant and different inflammatory lung lesions showed varying degrees of uptake of [ 18 F]AlF-NOTA-FAPI-04 and [ 18 F]FDG. • Inflammatory lung lesions showed significantly less uptake than malignancies, and uptake varied among different types of inflammatory lesions. • Both types of PET/CT could differentiate malignant and various inflammatory lung findings., (© 2023. The Author(s), under exclusive licence to European Society of Radiology.)

Positron emission tomography-computed tomography (PET/CT) is an efficient method for the diagnosis of various types of human cancer. Studies have demonstrated that Gd2O3-doped carbon-11-choline (GdCho) can be used as a contrast nanoparticle for PET/CT in the diagnosis of patients with lung cancer. The aim of the present study was to evaluate the effect of GdCho-lenvatinib nanoparticles contrast-PET/CT (GdCho-Len-PET) in the diagnosis and treatment planning of a cohort of patients suspected of having lung cancer. The results of the present study demonstrated that GdCho-Len could be used as an efficient PET/CT contrast agent for the diagnosis of patients with lung cancer. GdCho-Len nanoparticles contrast agent exhibited a significantly improved longitudinal relaxivity compared with GdCho. The outcomes of the present study were that GdCho-Len-PET diagnosed 152 patients with lung cancer, whereas GdCho-PET diagnosed 130 patients with lung cancer among the 172 patients. GdCho-Len-PET presented with higher accuracy and sensitivity compared with GdCho-PET in diagnosing patients with lung cancer. All patients were further confirmed via histological analysis. GdCho-Len-PET contributed to the anticancer treatments in 56 out of 62 (90.3%) patients with lung cancer who were candidates for radiation therapy, 52 out of 57 (91.2%) patients with lung cancer undergoing adjuvant radiotherapy, and 13 out of 17 (76.5%) patients with lung cancer undergoing comprehensive therapy. Patients diagnosed using GdCho-Len-PET improved the survival of patients with lung cancer during a 420-day follow up. In conclusion, GdCho-Len-PET increased the diagnostic efficacy and had a significant effect on survival for patients with lung cancer, and may therefore serve as a reliable method for human cancer diagnosis. [ABSTRACT FROM AUTHOR]

Löfgren's syndrome is an acute form of sarcoidosis that is characterised by articular symptoms, erythema nodosum and bilateral hilar lymphadenopathy. This syndrome is rare in Japan. We report a 62-year-old Japanese woman with Löfgren's syndrome and describe the articular manifestations as evaluated by multiple imaging modalities. Musculoskeletal ultrasound, magnetic resonance imaging and positron emission tomography-computed tomography findings indicated periarticular and subcutaneous inflammation. These imaging modalities facilitated the diagnosis of Löfgren's syndrome and helped differentiate from other rheumatic diseases. [ABSTRACT FROM AUTHOR]

Objectives: We reviewed PET/CT findings of pneumoconiosis and determined the ability of PET/CT to differentiate lung cancer from progressive massive fibrosis (PMF), and metastatic lymph nodes (LNs) from underlying reactive LN hyperplasia.Methods: This was a retrospective study of patients with pneumoconiosis and suspected lung cancer. Maximum standardized uptake value (SUVmax), long- and short-axis diameters (DL and DS), ratio of DL to DS (DL/S), and Hounsfield unit (HU) from the lung mass and mediastinal LNs were measured. The cutoff values of each parameter were obtained by ROC analysis, and we evaluated the diagnostic sensitivity.Results: Forty-nine pneumoconiosis patients were included. Eighty-three lung masses were detected, of which 42 were confirmed as lung cancer (23 squamous cell carcinomas, 12 adenocarcinomas, and 7 small cell carcinomas) and 41 were PMF. There were significant differences between lung cancer and PMF in terms of SUVmax, DS, DL/S, and HU (all p < 0.05). The sensitivity, specificity, and accuracy for diagnosis of lung cancer were 81.0%, 73.2%, and 77.1%, respectively, with an SUVmax cutoff value of 7.4; and 92.8%, 87.8%, and 90.4%, respectively, with a HU cutoff value of 45.5. Among the 40 LNs with available pathological results, 7 were metastatic. Metastatic LNs showed higher SUVmax, larger DS, and lower HU than benign lesions (all p < 0.05). The sensitivity, specificity, and accuracy for predicting metastatic LNs by PET/CT were 85.7%, 93.9%, and 92.5%, respectively.Conclusion: By applying PET and CT parameters in combination, the accuracy for differentiating malignant from benign lesions could be increased. PET/CT can play a central role in the discrimination of lung cancer and PMF.Key Points: • Lung cancer showed significantly higher SUVmax than PMF. • Lung cancer showed similar D L but longer D S , resulting in a smaller D L/S than PMF. • SUVmax demonstrated additive value in differentiating lung cancer from PMF, compared with HU alone. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the prognostic relevance of early risk stratification in diffuse large B-cell lymphoma (DLBCL) using interim Deauville score on positron emission tomography-computed tomography (PET-CT) scan and baseline International Prognostic Index (IPI). This retrospective study included 220 patients (median age, 64 years; men, 60%) diagnosed with DLBCL between 2007 and 2016 at our institution, treated with rituximab-based chemotherapy. Interim PET-CT was performed after three cycles of immuno-chemotherapy. Interim Deauville score was assessed as 4 or 5 in 49 patients (22.3%), and 94 patients (42.7%) had high-intermediate or high-risk IPI scores. In multivariate analysis, interim Deauville score (1-3 and 4-5) and baseline IPI (low/low-intermediate and high-intermediate/high) were independently associated with progression-free survival (for Deauville score, hazard ratio [HR], 1.00 vs. 2.96 [95% confidence interval (CI), 1.83-4.78], P < 0.001; for IPI, HR, 1.00 vs. 4.84 [95% CI, 2.84-8.24], P < 0.001). We stratified patients into three groups: low-risk (interim Deauville scores 1-3 and low/low-intermediate IPI), intermediate-risk (Deauville scores 1-3 with high-intermediate/high IPI or Deauville scores 4-5 with low/low-intermediate IPI), and high-risk (Deauville scores 4-5 and high-intermediate/high IPI). This early risk stratification showed a strong association with progression-free survival (HR, 1.00 vs. 3.98 [95% CI 2.10-7.54] vs. 13.97 [95% CI 7.02-27.83], P < 0.001). Early risk stratification using interim Deauville score and baseline IPI predicts the risk of disease progression or death in patients with DLBCL. Our results provide guidance with interim PET-driven treatment intensification strategies. [ABSTRACT FROM AUTHOR]

Objectives: This study compared the diagnostic ability of image-based parameters with texture parameters in the differentiation of hepatocellular carcinoma (HCC) and hepatic lymphoma (HL) by positron emission tomography–computed tomography (PET/CT). Methods: Patients with pathological diagnosis of HCC and HL were included in this study. Image-based and texture parameters were obtained by manual drawing of region of interest. Receiver operating characteristic (ROC) was used to test the diagnostic capacity of each parameter. Binary logistic regression was used to transform the most discriminative image-based parameters, texture parameters, and the combination of these parameters into three regression models. ROC was used to test the diagnostic capacity of these models. Result: Ninety-nine patients diagnosed with HCC (n = 76) and HL (n = 23, 10 primary HL, 13 secondary HL) by histological examination were included in this study (From 2011 to 2018, West China hospital). According to the AUC and p -value, 2 image-based parameters and five texture parameters were selected. The diagnostic ability of texture-based model was better than that of image-based model, and after combination of those two groups of parameters the diagnostic capacity improved. Conclusion: Texture parameters can differentiate HCC from HL quantitatively and improve the diagnostic ability of image-based parameters. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the radiation doses received by the positron emission tomography (PET)/computed tomography (CT) staff in three different diagnostic centers in Egypt. The whole-body effective dose measured by thermoluminescent dosimeters (TLDs) for staff working in PET and the effective dose per study received by physicist, technician, and nurse were measured by an electronic pocket dosimeter (EPD) during a period of 6 months. Statistical analysis was held between the measurements of the TLDs as well as for the EPD for the three studied PET-CT centers. After combining TLD and EPD prospective annual scores for the three studied categories in the three centers, the one-way ANOVA test results have shown that there were statistically significant differences between group means with respect to their TLD mean score (P = 0.041). The mean nurse group TLD score, across the three centers, appeared to be the lowest scoring 3.83 (standard deviation [SD] 0.012) compared to the physicist and technician who measured 4.62 (SD 0.231) and 6.92 (SD 0.018), respectively. Scheffe's test for complex comparisons revealed a significant difference between nurse group and technologist group (P = 0.001). Regarding the annual combined EPD scores, the post hoc test, namely Scheffe's test for complex comparisons, revealed a significant difference between nurse group and technologist group (P = 0.001). This was measured after the one-way ANOVA test results have shown that there were statistically significant differences between annual group EPD means (P = 0.032). Finally, there was no recorded significance for the studied categories across the three centers between their annual TLD and EPD dose scores (P = 0.072). Technicians group received the highest mean effective whole-body doses when compared with the International Commission on Radiological Protection dose limit, each individual worker can work with many more 18F-fluorodeoxyglucose (FDG) PET/CT studies for a (period time) without exceeding the occupational dose limits if the average received effective dose continues with the same rate. The study also confirmed that low levels of radiation dose are received by medical personnel involved in 18F-FDG PET/CT procedures in those centers due to implementing radiation protection measures and procedures. [ABSTRACT FROM AUTHOR]

Purpose: To investigate whether tumor texture features derived from pretreatment with 18F-fluorodeoxyglucose positron emission tomography (FDG PET) can predict histological response or event-free survival (EFS) in patients with localized osteosarcoma of the extremities treated by neoadjuvant chemotherapy (NAC).Methods: We retrospectively reviewed 35 patients with American Joint Committee on Cancer stage II extremity osteosarcoma treated with NAC and surgery. Primary tumor traditional parameters and texture features were measured for all 18F-FDG PET images prior to treatment. After surgery, histological responses to NAC were evaluated on the postsurgical specimens. A receiver operating characteristic curve (ROC) was constructed to evaluate the optimal predictive performance among the various indices. EFS was calculated using the Kaplan-Meier method and prognostic significance was assessed by Cox proportional hazards analysis.Results: Pathologic examination revealed 16 (45.71%) good responders and 19 (54.29%) poor responders. Although both the texture features (least axis, dependence nonuniformity, run length nonuniformity, and size zone nonuniformity) and metabolic tumor volume (MTV) can predict tumor response of osteosarcoma to NAC, the traditional indicator MTV has the best performance according to ROC curve analysis (area under the curve = 0.918, p < 0.0001). In multivariate analysis, MTV (p < 0.0001), histological response (p = 0.0003), and texture feature of coarsenessNGTDM (neighboring gray tone difference matrix) (p = 0.005) were independently associated with EFS.Conclusions: Intratumoral heterogeneity of baseline 18F-FDG uptake measured by PET texture analysis can predict tumor response and EFS of patients with extremity osteosarcoma treated by NAC, but the conventional parameter MTV provides better predictive power and is a strong independent prognostic factor.Key Points: • The baseline 18 F-FDG PET tumor texture features can predict tumor NAC response for patients with osteosarcoma. • Coarseness NGTDM is a new and independent prognostic factor for osteosarcoma. • MTV provides the best predictive power and is a strong independent prognostic factor for patients with osteosarcoma. [ABSTRACT FROM AUTHOR]

Objectives: To systematically determine the diagnostic accuracy of 18-fluorodeoxyglucose positron emission tomography/magnetic resonance imaging ([18F]FDG-PET/MRI) for the detection of liver metastases and evaluate the sources of heterogeneity in the reported results.Methods: PubMed and EMBASE databases were searched up until December 31, 2017, to identify original research studies reporting the diagnostic performance (Se and Sp) of PET/MRI for liver metastases, in comparison with PET/CT. Study quality was assessed using QUADAS-2. The summary Se and Sp of the studies were estimated using hierarchical modeling methods. To determine causes of study heterogeneity, the presence of a threshold effect was analyzed, and meta-regression analysis was performed.Results: Of 546 articles screened, eight suitable articles were identified, with seven for per-lesion analysis, and four for per-patient analysis. The meta-analytic summary Se and Sp for per-patient-based analysis were 99.2% (95% CI, 31.4-100.0%, I2 = 89.4%) and 98.6% (95% CI, 84.0-99.9%, I2 = 0.0%), respectively, while for per-lesion-based analysis they were 95.4% (95% CI, 78.3-99.2%, I2 = 99.7%) and 99.3% (95% CI, 93.8-99.9%, I2 = 96.5%). PET/MRI showed higher Se (95.4% vs. 68.3%) and Sp (99.3% vs. 95.8%) than PET/CT. Meta-regression analysis showed five significant factors affecting study heterogeneity: study subject characteristics, study design, MRI technique (DWI, HBP after injection of liver-specific contrast media), imaging review method, and reference standard.Conclusion: The diagnostic accuracy of [18F]FDG-PET/MRI for liver metastasis was high overall, but substantial heterogeneity was found. Further randomized controlled studies or prospective studies are needed to investigate the role of PET/MRI in liver metastasis in comparison with PET/CT.Key Points: • [ 18 F]FDG-PET/MRI has high meta-analytic Se and Sp for the diagnosis of liver metastasis. • PET/MRI using DWI and HBP images significantly increased diagnostic accuracy. • Study heterogeneity was associated with subject characteristics, study design, MRI technique, image review method, and reference standard. [ABSTRACT FROM AUTHOR]

Background: Freezing of gait (FOG) could be partly alleviated by dopaminergic drugs but the mechanism still needs to be elucidated. The purpose of this study is to explore the mechanisms of FOG by vesicular monoamine transporter VMAT2 distribution with the 18,F-AV133 tracer and 18-fludeoxyglucose positron emission tomography–computed tomography (18,F-FDG PET-CT). Methods: Clinical material and PET-CT data were collected from 20 patients with FOG and 147 patients without FOG from November 1, 2017 to October 31, 2018. Brain scans of all participants were acquired over an approximately 20-min period, 120 min after injection of approximately 250 MBq 18,F-AV133. The mean uptake ratios of different regions were identified by NeuroQ software of 18,F-FDG PET-CT. Data analysis included variance, chi-square analysis, covariance analysis, and logistic regression. Results: Our data showed that patients with FOG were provided with greater doses of dopaminergic drugs (p<0.05). The frequency of FOG was 11.98% and increased as Parkinson's disease progressed. FOG was more common in the elderly and strongly associated with the duration. Cognitive impairments were obvious, assessed by Mini-Mental State Examination and Montreal Cognitive Assessment (p<0.05). The VMAT2 distribution with 18,F-AV133 was decreased significantly in the caudate nucleus and lentiform nucleus while the metabolism of these areas was elevated, determined by 18,F-FDG PET-CT (p<0.05). The metabolism of the primary visual cortex decreased obviously in patients with FOG compared with those without FOG (p<0.05). Conclusion: FOG mainly occurred in the advanced stage, and was strongly associated with the duration and larger dose of dopaminergic drugs. The dopamine level of the nigrostriatal system decreased significantly and the uptake ratios of the primary visual cortex dropped obviously in the FOG group compared with the non-FOG group. Our study suggests that both the dopaminergic pathway and the primary visual cortex are involved in the pathogenesis of FOG. [ABSTRACT FROM AUTHOR]

Purpose: The aim of the study was to correct for partial volume effect in positron emission imaging studies which is the most influential factors using three-dimensional (3D) representation of the recovery coefficients (RCs) to improve standardized uptake value (SUV) calculations.Methods: Several phantom studies were conducted at significantly wide range of lesion contrast, range 2:1 up to 15:1. It was then classified into two groups: one for generating 3D function taking into consideration the sphere size as well lesion contrast whereas the other group was used for functions validation. A segmentation threshold algorithm for lesion delineation and volume determination was generated based on lesion contrast and lesion size. In addition, five 3D functions of the RC of the SUV were formulated considering lesion size and lesion contrast. Validation of the new algorithms has considered both phantom and clinical studies.Results: The error in threshold 3D function was well below 10%. For lesions ≤ 2 cm in diameter, there was no statistical difference of the functions developed for SUVmax as well as those functions generated for SUVmean. However, the median SUVmax has increased significantly when compared with data before correction. For SUVmean, the increase in median value was also significantly high.Conclusion: It has been successful to generate 3D mathematical formulations of the SUV RC taking into consideration the most influential factors including lesion size and lesion contrast. Validation studies were suggestive of the good performance of the new mathematical algorithms generated to correct for PVE. However, further studies are underway to ensure the performance of the proposed algorithms in clinical PET studies. [ABSTRACT FROM AUTHOR]

Background: Evidence suggests that psoriasis might be associated with metabolic syndrome and an increased risk for cardiovascular disease.Objective: To determine whether ustekinumab reduces systemic and vascular inflammation associated with metabolic syndrome and cardiovascular disease, measured using 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET/CT).Methods: Patients with psoriasis and healthy controls underwent baseline 18F-FDG PET/CT imaging. Patients with moderate-to-severe psoriasis were treated with ustekinumab and underwent 18F-FDG PET/CT again after a Psoriasis Area and Severity Index of 75 was achieved.Results: After a Psoriasis Area and Severity Index of 75 was achieved with ustekinumab treatment, standardized uptake values were reduced in the liver, spleen, and 5 parts of the aorta (P < .05).Limitations: Our study does not provide outcome data concerning cardiovascular events or metabolic syndrome; it only shows surrogate markers in a limited (Korean) population.Conclusion: Ustekinumab treatment was significantly associated with decreased systemic and vascular inflammation related to metabolic syndrome and cardiovascular disease among patients with psoriasis. [ABSTRACT FROM AUTHOR]

Purpose of the Study: To assess the efficacies of Tc-99m glucoheptonate single photon emission computed tomography-computed tomography (Tc-99m GHA SPECT-CT) and N-13 ammonia positron emission tomography-computed tomography (N-13 NH3PET-CT) in detecting recurrent glioma. Materials and Methods: Fifty-five consecutive, histologically proven, and previously treated glioma patients (age, 38.9 ± 12.2 years; 61.8% males) presenting with clinical suspicion of recurrence were evaluated with Tc-99m GHA SPECT-CT and N-13 NH3PET-CT. Images were evaluated both qualitatively and semiquantitatively. A combination of clinicoradiological follow-up, repeat imaging, and/or biopsy (when available) was considered as the reference standard. Results: Based on the reference standard, 28/55 (50.9%) patients had recurrence. Sensitivity, specificity, positive predictive value, negative predictive value, accuracy of Tc-99m GHA SPECT-CT, and N-13 NH3PET-CT were 85.7%, 85.2%, 85.7%, 85.2%, 85.5% and 78.6%, 88.9%, 88.0%, 80.0%, 83.6%, respectively (concordant findings in 46 patients). The performances of the two modalities were equivalent both in overall and subgroup McNemar analyses (P = 0.508, overall; P = 0.687, low grade; P = 1.000, high grade). Conclusion: Tc-99m GHA SPECT-CT is an alternative imaging modality equally efficacious as N-13 NH3PET-CT in detecting recurrent glioma. [ABSTRACT FROM AUTHOR]

Study Design: A meta-analysis.Objective: The aim of this study was to compare the diagnostic accuracies of F-18 fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET) and magnetic resonance imaging (MRI) for the detection of spondylodiscitis through a meta-analysis.Summary Of Background Data: There is no meta-analysis study that compares the diagnostic accuracies of F-18 FDG PET and MRI for the detection of spondylodiscitis.Methods: The MEDLINE and EMBASE databases were searched from the earliest available date of indexing to January 10, 2018 for studies comparing the diagnostic performance F-18 FDG PET with that of MRI for the detection of spondylodiscitis. We determined the sensitivities and specificities across studies, calculated the positive and negative likelihood ratios (LR+ and LR-), and constructed the summary receiver operating characteristic curves.Results: In the seven studies (212 patients) selected, the pooled sensitivity and specificity of F-18 FDG PET were 0.95 (95% confidence interval [CI]: 0.87-0.98) and 0.88 (95% CI: 0.73-0.95), respectively. The LR syntheses showed an overall LR+ of 7.6 (95% CI: 3.4-17.2) and LR- of 0.05 (95% CI: 0.02-0.14). The pooled diagnostic odds ratio was 141 (95% CI: 44-444). The pooled sensitivity and specificity of MRI were 0.85 (95% CI: 0.65-0.95) and 0.66 (95% CI: 0.48-0.80), respectively. The LR syntheses showed an overall LR+ of 2.5 (95% CI: 1.5-4.2) and LR- of 0.22 (95% CI: 0.08-0.60). The pooled diagnostic odds ratio was 11 (95% CI: 3-42). In the meta-regression analysis, no variable was identified as the source of the study heterogeneity.Conclusion: The current meta-analysis shows that F-18 FDG PET has better diagnostic accuracy than MRI for the detection of spondylodiscitis. Further large multicenter studies would be necessary to substantiate the diagnostic accuracies of F-18 FDG PET and MRI for spondylodiscitis.Level Of Evidence: 2. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the prognostic value of FDG PET/CT metabolic parameter compared to clinico–pathological risk factors in surgical margin-negative stage IA non-small cell lung cancer (NSCLC) patients. Methods: 167 patients with consecutive FDG PET/CT scans from 2009 to 2015 performed for staging of NSCLC stage IA with plans for curative surgery were retrospectively reviewed. Maximum standardized uptake value (SUVmax) of primary tumor and mean SUV of liver were acquired from PET/CT. Tumor-to-liver SUV ratio (TLR) was calculated. Charts were reviewed to obtain basic patient characteristics (age, sex, smoking history, LDH, histologic subtype) and high-risk factors for adjuvant chemotherapy (tumor size, poorly differentiation, vascular invasion, and sub-lobar resection). Patients were dichotomized into two groups using optimal cut-off from receiver operating characteristic curve analysis of TLR to predict recurrence. Statistical analysis was done using Cox regression analysis and Kaplan–Meier method. Factors with P < 0.2 in univariate analysis were included in multivariate analysis. Results: Recurrence rate was 12.6% (21/167). Median disease-free survival (DFS) was 47.2 months while 2-year and 5-year DFS rates were 93% and 86%, respectively. The optimal cut-off for TLR was 2.3. In univariate analysis, P value of sex, vascular invasion, and TLR were less than 0.2. In multivariable analysis, high TLR was the only factor that showed significant association with tumor recurrence (hazard ratio 3.795, P = 0.0048). Conclusions: TLR was an independent prognostic factor for recurrence and TLR could be an important risk factor to be considered in decision-making for adjuvant chemotherapy, even for those with stage IA NSCLC. [ABSTRACT FROM AUTHOR]

Seborrhoeic keratosis is a common benign skin tumor and can have a variable presentation. Irritated seborrhoeic keratosis can clinically mimic cutaneous malignancy and often warrant biopsy. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) can give false-positive results in many cutaneous pathologies. We present an interesting case of irritated seborrhoeic keratosis masquerading as skin cancer, clinically as well as on18F-FDG PET-CT. [ABSTRACT FROM AUTHOR]

Serum carbohydrate antigen 19-9 (CA 19-9), a marker of malignant tumors, is generally slightly elevated in benign conditions. We report a case of acute cholecystitis with a significantly elevated level of serum CA 19-9 based on positron emission tomography (PET)-computed tomography (CT) findings. A 65-year-old woman presented with abdominal pain and fever. A CT image revealed an enlarged gallbladder without tumor shadows. The C-reactive protein (CRP) level was elevated to 7.66 mg/dl. Moreover, the serum CA 19-9 level was significantly elevated to 19,392 U/ml. We started antibiotic treatment, because we suspected acute cholecystitis, but still, we could not ignore the possible presence of malignant tumors. After 11 days of antibiotic treatment, serum CRP and CA 19-9 levels decreased to 0.11 mg/dl and 1,049 U/ml, respectively. There was an accumulation of fluorine 18-labeled fluorodeoxyglucose (maximum standardized uptake value, 9.3) without tumor shadows in the liver, near the gallbladder, on the PET-CT examination. We considered the possibility that the inflammation had spread from the gallbladder to the liver, made a diagnosis of acute cholecystitis, and performed a cholecystectomy 33 days after treatment initiation. The serum CA 19-9 level decreased to 45 U/ml after the surgery. One year after the surgery, the patient was alive, and the serum CA 19-9 level was 34 U/ml. Acute cholecystitis with a significantly high elevation of the serum CA 19-9 level is rare. In such cases, it is important to confirm the change in the serum CA 19-9 level over time after antibiotic treatment and perform imaging studies to distinguish between inflammation and malignancy.

Ectopic thyroid tissue is very rare, but its prevalence increases in those with thyroid pathology. It typically occurs due to aberrant development of the thyroid gland during its migration to the pretracheal region. In this report, there are two cases of mediastinal ectopic thyroid tissue discussed, which were initially considered to be malignancies. The hospital course, diagnostic workup, including the use of computed tomography and positron emission tomography scans, and the characteristic features of the tissue are examined here. Due to the imaging characteristics, it is important to consider ectopic thyroid tissue as a differential diagnosis for mediastinal masses as encountered in these cases. Asymptomatic ectopic thyroid tissue is usually treated medically; however, patients in both of our cases opted for surgical resection of the masses even after confirmation of the origin of the tissues.

Lung cancer commonly metastasizes to ipsilateral and contralateral lungs, to mediastinal lymph nodes, to skeletal level, to brain, and to adrenal gland. It is indeed very rare to find skeletal metastases at the extremities, especially at the onset of the disease. We share the case of a 53-year-old man with dyspnea and pain at the level of the first finger of the left hand under antibiotic treatment for suspected osteomyelitis. 18F-fluorodeoxyglucose positron emission tomography–computed tomography showed the presence of a left lung lesion with multiple localizations at muscles and bones. [ABSTRACT FROM AUTHOR]

Standardized uptake value (SUV) is an advanced tool for quantitative tumor identification and metabolic target volume delineation (TVD) in diagnostic and therapeutic settings. It is thus important to establish a quality assured process to maintain the traceability of data correctly by positron emission tomography (PET) systems. Patient administration of 18 fluoro-deoxy-glucose is increasingly delivered by automated infusion systems (AISs). Whenever AIS is used, its accuracy and traceability measurement need verification. In addition, it was observed that the unreproducible SUV displayed in PET and the treatment planning system (TPS) may cause grave concerns for radiation oncologists for TVD. This concern may complicate the correlation of TVD on PET and TPS and their clinical reporting. The SUV traceability was established from the PET system to AIS. Its accuracy was verified by cross-referencing to the reference dose calibrator traceable to a primary standard. The SUV values were converted in TPS using the in-house "clinical tool" to be identical as in PET, to allow radiation oncologists to use SUV confidently. The outcome of this study enables the clinical groups to rely on the correct SUV values displayed on the TPS and to improve the quality of care for patients in clinical procedures.

Sparganosis is a rare parasitic disease caused by the migrating plerocercoid larva of Spirometra species tapeworms. The most frequent clinical manifestation is a subcutaneous nodule resembling a neoplasm. In this study, we presented multimodal findings of ultrasonography, computed tomography, magnetic resonance imaging, positron emission tomography-computed tomography and follow-up imagings on multifocal sparganosis, mimicking lymphoma involvement in a patient with lymphoma.

Fever of unknown origin (FUO) is a convoluted clinical dilemma. It can be caused by infective, inflammatory, malignant, and other pathologies. The identification of etiopathogenesis is essential for instituting definitive management. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET-CT) is now an integral part of FUO management. We present the case of a 60-year-old female with autosomal dominant polycystic kidney disease (ADPKD), where the infected renal cyst was detected as the cause of FUO on18F-FDG PET-CT [ABSTRACT FROM AUTHOR]

Background: Research on the relationship between neuron-specific enolase (NSE) levels and normal organs, particularly the central nervous system, in small cell lung cancer is limited. Therefore, this study aimed to investigate the relationship between positron emission tomography-computed tomography (PET-CT) accumulation at hypothalamic/pituitary regions, tumor activity, and NSE level in limited-stage small cell lung cancer. We retrospectively analyzed patients who were diagnosed with limited-stage small cell lung cancer at Tokyo Medical University Hospital between July 1, 2019, and May 31, 2023, and were treated with chemoradiotherapy or radiotherapy. Leukocytes, erythrocytes, hemoglobin, platelets, total protein, albumin, NSE, and carcinoembryonic antigen were measured in blood samples obtained before treatment initiation. The maximum standardized uptake value (SUVmax), volume, and total lesion glycolysis (TLG) of each hypothalamic /pituitary region, primary tumor, and lymph node metastases were extracted from PET-CT images. The total tumor volume (primary tumor volume plus lymph node metastases volume) and total TLG (primary tumor TLG plus lymph node metastases TLG) were calculated., Results: This study included 19 patients (mean age, 70.1 ± 8.8 years; 13 men and 6 women); the pathology in all patients was small cell lung cancer. Patients were classified into two groups according to the NSE reference value (16.3 ng/mL): six patients having NSE level below the reference value and 13 having NSE level above the reference value. The SUVmax in the hypothalamic/pituitary region was 2.95 in the NSE < 16.3 ng/mL group and 4.10 in the NSE > 16.3 ng/mL group, with a statistically significant difference (p = 0.03). The total tumor volume was 17.8 mL in the NSE < 16.3 ng/mL group and 98.9 mL in the NSE > 16.3 ng/mL group, with a statistically significant difference (p < 0.01). A correlation coefficient of r = 0.458 (p = 0.0486) was observed between SUVmax in the hypothalamus/pituitary and NSE level. A correlation coefficient of r = 0.647 (p < 0.01) was also observed between total tumor volume and NSE level. Finally, a correlation coefficient of r = 0.53 (p = 0.01) was observed between hypothalamic/pituitary TLG and primary tumor TLG., Conclusions: The findings demonstrated a correlation between hypothalamic/pituitary activity and tumor activity, suggesting the prognostic significance of NSE., (© 2024. The Author(s).)

Background: Salvage radiation therapy (SRT) and surveillance for low-risk prostate-specific antigen (PSA) recurrence have competing risks and benefits. The efficacy of early SRT to the prostate bed with or without pelvic lymph nodes compared to surveillance in patients with PSA recurrence after radical prostatectomy and no identifiable recurrent disease evident on prostate specific membrane antigen-positron emission tomography/computer tomography (PSMA-PET/CT) is unknown., Study Design: The Dedicated Imaging Post-Prostatectomy for Enhanced Radiotherapy outcomes (DIPPER) is an open-label, multicentre, randomised Phase II trial., Endpoints: The primary endpoint is 3-year event-free survival, with events comprising one of PSA recurrence (PSA ≥0.2 ng/mL higher than baseline), radiological evidence of metastatic disease, or initiation of systemic or other salvage treatments. Secondary endpoints include patient-reported outcomes, treatment patterns, participant perceptions, and cost-effectiveness., Eligibility Criteria: Eligible participants have PSA recurrence of prostate cancer after radical prostatectomy, defined by serum PSA level of 0.2-0.5 ng/mL, deemed low risk according to modified European Association of Urology biochemical recurrence risk criteria (International Society for Urological Pathology Grade Group ≤2, PSA doubling time >12 months), with no definite/probable recurrent prostate cancer on PSMA-PET/CT., Patients and Methods: A total of 100 participants will be recruited from five Australian centres and randomised 1:1 to SRT or surveillance. Participants will undergo 6-monthly clinical evaluation for up to 36 months. Androgen-deprivation therapy is not permissible. Enrolment commenced May 2023., Trial Registration: This trial has been registered with the Australian New Zealand Clinical Trials Registry (ACTRN: ACTRN12622001478707)., (© 2023 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is a rare subtype of non-Hodgkin lymphoma (NHL) with poor prognosis, particularly in relapsed or refractory patients. Thus, timely detection of relapse and appropriate disease management are crucial. We present two patients with ENKTL, wherein positron emission tomography-computed tomography (PET-CT) with total-body coverage after induction therapy, detected newly relapsed regions in the bone marrow of the lower leg prior to progression. Case 1: A 47-year-old woman with nasal obstruction, showing 18F-fluoro-deoxyglucose (FDG) uptake in the nasal cavity (Lugano stage IE). After induction therapy (RT-2/3 DeVIC), PET-CT revealed abnormal uptake only in the right fibula. Case 2: A 68-year-old man with a skin nodule/ulcer and an enlarged right inguinal lymph node was diagnosed with advanced ENKTL. A PET-CT scan revealed abnormal uptake in the subcutaneous mass of the right medial thigh, lymph nodes, and descending colon (Lugano stage IV). After induction therapy, PET-CT revealed new abnormal uptake only in the left tibia. In both patients, CT-guided biopsy confirmed ENKTL recurrence. Moreover, PET-CT with whole-body coverage was useful for the timely assessment of relapse and detection of asymptomatic bone involvement. This approach allowed for modifications to treatment strategies in certain patients.

Purpose: To identify prognostic clinical and imaging parameters for patients with neuroendocrine liver metastases (NELMs) undergoing transarterial radioembolization (TARE)., Materials and Methods: Forty-seven patients (27 men; mean age, 64 years) with NELMs who received TARE, along with pre-procedure liver MRI and 68 Ga-DOTATATE positron emission tomography/computed tomography were included. Apparent diffusion coefficient and standardized uptake value (SUV) of three liver metastases, normal spleen and liver were measured. SUVmax or SUVmean were used for the calculation of tumor-to-organ ratios (tumor-to-spleen and tumor-to-liver ratios) using all possible combinations (including SUVmax/SUVmax, SUVmax/SUVmean, and SUVmean/SUVmean). Clinical parameters (hepatic tumor-burden, presence of extra-hepatic metastases, chromograninA, Ki-67 and bilirubin levels) were assessed. Overall survival, progression-free survival (PFS) and hepatic progression-free survival (HPFS) were calculated using Kaplan-Meier curves., Results: Median overall survival, PFS and HPFS were 49.6, 13.1 and 28.3 months, respectively. In multivariable Cox regression analysis, low Ki-67 (≤ 5%), low hepatic tumor-burden (< 10%), absence of extrahepatic metastases, and increased Tmean/Lmax ratio were significant prognostic factors of longer overall survival and HPFS. High baseline chromograninA (> 1330 ng/mL) was associated with shorter HPFS. Tmean/Lmax > 1.9 yielded a median overall survival of 69 vs. 33 months (P < 0.04), and a median HPFS of 30 vs. 19 months (P = 0.09). For PFS, high baseline SUVmax of NELMs was the single significant parameter in the multivariable model. SUVmax > 28 resulted in a median PFS of 16.9 vs. 6.5 months, respectively (P = 0.001)., Conclusion: High preinterventional Tmean/Lmax ratios, and high SUVmax on 68 Ga-DOTATATE positron emission tomography/computed tomography seem to have prognostic value in patients with NELMs undergoing TARE, potentially aiding patient selection and management alongside conventional variables., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest related to this work to declare., (Copyright © 2023 Société française de radiologie. Published by Elsevier Masson SAS. All rights reserved.)

Artifacts in nuclear medicine imaging are not uncommon. We are aware of some of these, for which we follow necessary protocols to avoid them. However, there are some unusual and unavoidable artifacts that we come across in daily imaging, which may be of concern and need to be detected and corrected on time. Hence, sharing a few such unusual artifacts we encountered while performing routine studies on positron emission tomography-computed tomography and gamma cameras, evaluating the cause and possible precautions., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Indian Journal of Nuclear Medicine.)

Watchful waiting is an acceptable management strategy for advanced-stage, low tumor burden (LTB) patients with follicular lymphoma (FL). However, the prediction of how long this treatment-free observation period will last remains imperfect. We explored whether total metabolic tumor volume (TMTV) and other positron emission tomography parameters were predictive of time to first treatment (TTFT). We analyzed 97 grade 1-3A advanced-stage LTB FL patients and found that a high TMTV was associated with other tumor burden features at diagnosis. Patients with a TMTV above our established cutoff of 50 mL had a significantly shorter median duration of observation (2.6 vs. 8.8 years; p = 0.001). At 5 years, 77% of patients with a high TMTV and 46% of patients with a low TMTV required treatment. In the multivariable analysis, a high TMTV was the only independent factor predicting TTFT (hazard ratio = 2.09; p = 0.017). Overall, TMTV is a strong predictor of the duration of observation in LTB FL patients. Upon validation of our cutoff in external series and standardization of the methodology, the TMTV could become an additional factor to consider deferring or initiating treatment in otherwise LTB patients., (© 2023 The Authors. Hematological Oncology published by John Wiley & Sons Ltd.)