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Introduction: The expression of alpha-five beta-three (αVβ3) integrins is upregulated in various malignancies undergoing angiogenesis. The development of integrin antagonists as diagnostic probes makes the αVβ3 integrin a suitable candidate for targeting tumor angiogenesis. The goal of this study was to optimize the radiolabeling and evaluate the potential of conjugated integrin antagonist carbamate (IAC), a peptidomimetic, as a theranostic radiopharmaceutical for targeting tumor angiogenesis. Methodology: Radiolabeling of DOTAGA [2,2',2"-{10-(2,6-dioxotetrahydro-2H-pyran-3-yl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl} triacetic-acid]-IAC with [ 68 Ga]Ga, [ 177 Lu]Lu, and [ 225 Ac]Ac was optimized. The binding affinity (K d ) of DOTAGA-IAC for the αVβ3 receptor and cancer cell lines was quantified. The biodistribution studies were conducted in healthy Wistar rats. Dosimetry analysis was performed on [ 177 Lu]Lu-DOTAGA-IAC distribution data. A pilot study of [ 68 Ga]Ga-DOTAGA-IAC and [ 18 F]FDG Positron Emission Tomography (PET/CT) imaging was performed in five patients with histopathologically confirmed breast cancer. PET/CT findings were compared between [ 68 Ga]Ga-DOTAGA-IAC and [ 18 F]FDG in these patients. Results: Radiopharmaceuticals were prepared with high radiochemical purity (>99.9%). K d and B max measurements were 15.02 nM and 417 fmol for αVβ3 receptor protein: 115.7 nM and 295.3 fmol for C6 glioma cells. Biodistribution studies in rats suggested the excretion via kidneys and partially through the hepatobiliary route. The effective dose of [ 177 Lu]Lu-DOTAGA-IAC was found to be 0.17 mSv/MBq. The dynamic study in patients revealed the optimal imaging time to be 30-35 mins postadministration. Out of the cohort, [ 68 Ga]Ga-DOTAGA-IAC detected the primary lesions in all five patients with a mean standard uptake value (SUV max ) of 3.94 ± 0.58 compared with [ 18 F]FDG (SUV max 13.8 ± 6.53). Conclusion: The study demonstrates that DOTAGA-IAC exhibits strong binding to αVβ3 integrin, positioning it as a promising PET agent for assessing primary and metastatic cancers. The outcomes from the pilot study suggest the potential of [ 68 Ga]Ga-DOTAGA-IAC PET/CT in breast carcinoma diagnosis. While recognizing the theranostic potential of DOTAGA-IAC for αVβ3 integrin-expressing tumors, further clinical investigations are warranted to comprehensively assess therapeutic efficacy.

Rationale and Objectives: Fibroblast Activation Protein (FAP) expressing cancer-associated fibroblasts has been a major breakthrough causing a paradigm shift in targeted theranostics focusing on the tumor microenvironment. In this study, a squaric acid derivative DOTA.SA.FAPi (SA.FAPi) has been evaluated as a potential diagnostic probe in diverse epithelial cancers and compared to the standard-of-care 18 F-FDG., Methods: 25 patients enrolled in this prospective study underwent 18 F-FDG and 68 Ga-SA.FAPi PET scans on two different days. For biodistribution, standardized uptake values (SUV) were computed by delineating region-of-interest on various body organs. For comparative analysis in disease identification, lesion tracer uptake was quantified using SUVs corrected for lean body mass (SUL), SUV max , tumor-to-background ratio (TBR) with liver and blood pool as the reference, total lesion glycolysis (TLG for 18 F-FDG) and total lesion FAP expression (TLF for 68 Ga-SA.FAPi)., Results: 25 patients (mean age: 58 ± 8 years) with four types of cancers including hepatocellular carcinoma (HCC, 56% of cohort), gall bladder carcinoma (GB Ca, 12%), adrenocortical carcinoma (ACC, 16%), and breast carcinoma (breast Ca, 16%) were prospectively evaluated. Physiological tracer uptake of 68 Ga-SA.FAPi was noted in the salivary glands, thyroid, liver, pancreas, muscles and kidneys with variable uptake in the lacrimal glands, extra-ocular muscles, oral mucosa and uterus. Lesion-based comparative analysis between both the radiotracers demonstrated complete concordant findings in detection of all primary lesions and distant metastases in liver, bones, adrenals and peritoneum whereas discordant findings were noted in lung nodules (20%) and lymph nodes (13%). In overall analysis, 68 Ga-SA.FAPi exhibited significantly higher SUV max (10.3 vs 8.8, p-0.019), SUL peak (6.8 vs 4.9, p-0.000) and SUL avg (5.4 vs 4.1, p-0.019) in comparison to 18 F-FDG whereas TBR was comparable for both the tracers [TBR Liver : median 1.9 (IQR: 2.6-1.4) vs 1.8 (2.6-1.1), p-0.275; TBR Bloodpool : 2.1 (3.7-1.4) vs 2.0 (2.7-1.4), p-0.207]. In subcategorical analysis, 68 Ga-SA.FAPi demonstrated higher SUV max , SUL peak and SUL avg values for primary disease (SUV max : 14.8 (18.7-9.7) vs (12.9-6.6), p-0.087; SUL peak : 8.2 (11.2-6.8) vs 6.3 (8.5-4.4), p-0.037; SUL avg : 6.9 ± 2.5 vs 5.1 ± 2.2, p-0.023] and distant metastases (8.8 vs 7.2, p-0.038); 6.3 (8.8-4.4) vs 3.6 (4.4-2.0), p-0.000; 5.4 vs 3.5, p-0.000] whereas comparable values were noted for both the tracers in nodal metastases [9 (13.5-4.1) vs 8 (12.7-4.7), p-0.726; 4.5 (6.2-1.8) vs 4.3 (5.7-2.2), p-0.727; 4.1 ± 2.3 vs 3.7 ± 1.8, p-0.129]. In primary disease, highest 68 Ga-SA.FAPi avidity was noted in ACC followed by GB Ca and HCC. In distant metastases, gall bladder, lung and skeletal lesions demonstrated higher 68 Ga-SA.FAPi avidity. Moreover, 68 Ga-SA.FAPi identified five additional lung lesions which were missed by 18 F-FDG in one case of ACC., Conclusion: 68 Ga-SA.FAPi emerged as an effective, versatile diagnostic probe for imaging various epithelial malignancies similar to 18 F-FDG., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Jaya Shukla reports financial support was provided by Post Graduate Institute of Medical Education and Research., (Copyright © 2024 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

Background: Targeted radionuclide therapy with Actinium-225-labeled prostate-specific membrane antigen ligands ( 225 Ac-PSMA) has emerged as a promising treatment modality in the management of metastatic castration-resistant prostate cancer (mCRPC). With its high linear energy transfer and short path length, 225 Ac induces double-stranded DNA breaks and is expected to have excellent efficacy and safety profile. This systematic review was conducted to precisely evaluate the role of 225 Ac-PSMA radioligand therapy (RLT) in mCRPC., Methods: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Searches were made using relevant keywords in the PubMed, Embase, and Scopus databases, and articles up to December 2020 were included. Data on efficacy and toxicity were extracted from the individual articles. Random-effects model was used for generating pooled estimates through meta-analysis., Results: Ten articles comprising 256 patients were included. Overall, 62.8% (95% confidence interval, CI: 53.4-71.7%) of the patients treated with 225 Ac-PSMA RLT achieved biochemical response, i.e., ≥50% decline in the serum prostate-specific antigen levels from baseline. Molecular response on Gallium-68 PSMA positron emission tomography/computed tomography was noted in 74% (95% CI: 50.1-92.1%) of the patients. The pooled estimates of median progression-free survival and overall survival were 9.1 months (95% CI: 3.6-14.5 months) and 12.8 months (95% CI: 4.5-21.0 months), respectively. The most commonly reported adverse event was xerostomia, which was observed in 72.7% (95% CI: 50.5-90.1%) of the patients. However, clinically significant toxicity was limited with grade ≥3 xerostomia, anemia, leucopenia, thrombocytopenia, and nephrotoxicity occurring in 1.2%, 12.3%, 8.3%, 6.3%, and 3.8% of the patients, respectively. Treatment discontinuation due to adverse events was noted in 20/208 patients., Conclusions: 225 Ac-PSMA RLT is an efficacious and safe treatment option for patients with mCRPC. Future randomized controlled trials are required to establish its therapeutic efficacy and survival benefit vis-à-vis other approved treatment modalities., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Purpose: Development of a novel theranostic radiopharmaceutical for estrogen receptor, expressing unresectable primary and metastatic breast cancers., Methods: Tamoxifen was radiolabeled with Rhenium-188 (Re-188) through tricarbonyl core. Radiolabeled complex was characterized by 1proton nuclear magnetic resonance spectroscopy and Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF). Various quality control tests such as sterility, apyrogenicity, and radiochemical purity (RCP) were performed to assess the suitability of the radiopharmaceutical for intravenous administration. In-vitro cell culture studies were performed for cytotoxic assessment. In addition to this, exposure due to different doses of Re-188-tricarbonyl tamoxifen was also calculated., Results: Re-188-tricarbonyl and Re-188-tricarbonyl tamoxifen showed more than 99% RCP. Sample was found to be sterile and pyrogens levels were within the permissible limit. Re-188-tricarbonyl tamoxifen was successfully characterized by MALDI-TOF and 1H-NMR spectroscopy. Re-188 (1.480 MBq) and tamoxifen (0.027 or 0.054 µM) individually showed 36 and 70% cell death, respectively. However, radiolabeled complex (Re-188-tricarbonyl tamoxifen) with the same amount of radioactivity (1.480 MBq) increased the cell death to more than 90% with one-fifth to one-tenth molar concentration of tamoxifen (0.0054 μM)., Conclusion: Re-188-tricarbonyl tamoxifen can be synthesized in-house in radiopharmacy lab. Radionuclide therapy with Re-188-tricarbonyl tamoxifen can be given using 10 times less amount of tamoxifen as compared to cold tamoxifen., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Targeted radionuclide therapies (TRT) using 131 I-metaiodobenzylguanidine ( 131 I-MIBG) and peptide receptor radionuclide therapy ( 177 Lu or 90 Y) represent several of the therapeutic options in the management of metastatic/inoperable pheochromocytoma/paraganglioma. Recently, high-specific-activity- 131 I-MIBG therapy was approved by the FDA and both 177 Lu-DOTATATE and 131 I-MIBG therapy were recommended by the National Comprehensive Cancer Network guidelines for the treatment of metastatic pheochromocytoma/paraganglioma. However, a clinical dilemma often arises in the selection of TRT, especially when a patient can be treated with either type of therapy based on eligibility by MIBG and somatostatin receptor imaging. To address this problem, we assembled a group of international experts, including oncologists, endocrinologists, and nuclear medicine physicians, with substantial experience in treating neuroendocrine tumors with TRTs to develop consensus and provide expert recommendations and perspectives on how to select between these two therapeutic options for metastatic/inoperable pheochromocytoma/paraganglioma. This article aims to summarize the survival outcomes of the available TRTs; discuss personalized treatment strategies based on functional imaging scans; address practical issues, including regulatory approvals; and compare toxicities and risk factors across treatments. Furthermore, it discusses the emerging TRTs., (©2021 American Association for Cancer Research.)

BACKGROUND. Early diagnosis is important in the overall management of prostate cancer (PCa). Gallium-68-labeled prostate-specific membrane antigen (PSMA) PET/CT has an established role in the detection of recurrent disease and staging of patients with intermediate- to high-risk PCa. However, only a small number of studies have evaluated its role in the initial diagnosis of PCa. OBJECTIVE. This systematic review was conducted to evaluate the diagnostic performance of 68 Ga-PSMA PET/CT in the initial detection of PCa in patients with clinical or biochemical findings suspicious for PCa. EVIDENCE ACQUISITION. This systematic review followed PRISMA guidelines. Searches in PubMed, Scopus, and Embase were conducted using relevant keywords, and articles published through April 30, 2020, were included. Using histopathology results as the reference standard, the numbers of true- and false-positives and true- and false-negatives were extracted. Pooled estimates of diagnostic test accuracy-including sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and summary ROC (SROC) curve-were generated using bivariate random-effects meta-analysis. EVIDENCE SYNTHESIS. Seven studies comprising 389 patients were included in the systematic review and meta-analysis. The pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio for the initial diagnosis of PCa using 68 Ga-PSMA PET/CT were 0.97 (95% CI, 0.90-0.99), 0.66 (95% CI, 0.52-0.78), 2.86 (95% CI, 1.95-4.20), and 0.05 (95% CI, 0.01-0.15), respectively. The test had high accuracy; the area under the SROC curve was 0.91 (95% CI, 0.88-0.93). CONCLUSION. Gallium-68-labeled PSMA PET/CT had excellent sensitivity and negative likelihood ratio in the initial diagnosis of PCa in patients with clinical or biochemical findings suspicious for PCa. CLINICAL IMPACT. Gallium-68-labeled PSMA PET/CT had high diagnostic accuracy for the initial detection of PCa in patients with clinical or biochemical findings suspicious for PCa and has potential utility as a rule-out test for these patients.

Background: Stomach wall uptake (SWU) of tracer in 99m Tc-MIBI myocardial perfusion imaging (MPI) occasionally leads to imaging artifacts, thereby lowering the diagnostic accuracy. It is less-studied phenomenon for possible link with proton pump inhibitors (PPIs) intake. This prospective work looked for association of SWU with PPI intake and compared its incidence with H 2 antagonists (H 2 A) users and patients not on either gastroprotective medication., Methods: One hundred fifty-six patients undergoing one day stress/rest 99m Tc-MIBI SPECT-MPI were distributed into four groups: control group (n = 48, not on any gastroprotective medication), PPI group (n = 47, on PPI treatment), H 2 A group (n = 19, on H 2 A therapy), and intervention group (N = 42, PPI discontinued for 3 days before MPI). Poststress planar images were analyzed for clinically relevant SWU., Results: Clinically relevant SWU was seen in 36% of PPI group patients compared to 8% in the control group, 10.5% in the H 2 A group, and 9.5% in the intervention group, respectively, with statistically significant difference. Only 1/40 patients undergoing exercise stress showed clinically relevant SWU compared to 26/116 patients undergoing adenosine stress (P = .020)., Conclusion: Patients on PPIs scheduled for vasodilator stress MPI may discontinue PPIs for 3 days, or replace with H 2 A to reduce the incidence of clinically relevant SWU associated with PPI therapy.

Estrogen receptor-expressing breast cancer exhibits better prognosis due to responsiveness to antiestrogen treatment. Therefore, knowledge of the estrogen receptor status of a tumor is an important prognostic and predictive indicator in breast cancer. We present noninvasive imaging of estrogen receptors with Tc tamoxifen that can identify the active tumor and approachable sites for biopsy. It may help in selection of patients for hormone replacement therapy and in assessment of receptor status in recurrent disease and also in response evaluation.

Breast cancer is the most common cancer in women with rising incidence worldwide. F-FDG PET/CT imaging has already established itself as a pivotal modality for staging, restating and response assessment in patients with carcinoma breast. The complex biology of this cancer is increasingly being decoded and various molecular targets have been identified and exploited for guiding the treatment at various time points during the course of the disease. We here depict a series of various metabolic and receptor targeting PET radiotracers in breast cancer patients which may help us understand the in vivo biology of this tumor.

Objective: To evaluate 18F-fluorodeoxyglucose (FDG) PET/CT in the assessment of disease activity, extent of the disease and response to therapy in relapsing polychondritis., Methods: Twenty-five patients (9 men, 16 women) with a mean age of 38.2 years (s.d. 13.7; range 18-62), diagnosed to have relapsing polychondritis according to Damiani and Levine's modification of McAdam's criteria, who underwent PET/CT examination were included. Ten patients underwent a second PET/CT examination after therapy or during follow-up. Clinical symptoms and auxiliary examination findings were recorded. PET/CT findings were reviewed and correlated with the clinical symptoms., Results: The major symptoms were aural pain (n = 21), nasal pain (n = 10), stridor (n = 5), cough (n = 9), fever (n = 8) and laryngeal tenderness (n = 8). The initial PET/CT was positive in 23/25 patients. PET/CT revealed involvement of auricular (n = 14), nasal (n = 8), laryngeal (n = 7), tracheobronchial (n = 6) and Eustachian (n = 3) cartilages with a mean maximum standardized uptake value (SUVmax) of 4.1 (s.d. 2.5; range 1.7-12.7). Fair correlation of aural/nasal pain/stridor with FDG avidity of cartilage involvement on PET/CT was noted. The key finding was detection of asymptomatic large airway involvement in seven patients (28%). Re-examination PET in 10 patients revealed complete therapeutic response (n = 5), partial response (n = 1), stable disease (n = 1), progressive disease (n = 1) and disease recurrence (n = 2)., Conclusion: FDG PET/CT is a useful tool for the assessment of the disease activity and extent. It identified activity in clinically inaccessible sites that are of clinical significance. It is also useful in assessing treatment response and finding relapse., (© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Aim: Thick-walled gallbladder is difficult to characterize on conventional imaging. 18F-FDG PET was used to differentiate benign and malignant wall thickness and compared with histopathology., Methods: Thirty patients with gallbladder (GB) wall thickening (focal > 4 mm and diffuse > 7 mm), underwents uspected on  ultrasound, or CT scan, and underwent 18F-FDG PET. Histopathology of the specimen was compared with imaging findings., Results: The mean age was 48.22 ± 31.33 years with a M:F 1:4 ratio. Twenty patients had diffuse and 10 had focal thickening. On 18F-FDG PET, lesion was benign in 12, malignant in 13, and indeterminate in 5. Histopathology was malignancy in 12; benign in 18-chronic cholecystitis in 11, xanthogranulomatous in 4, IgG4 related in 2, and polyp in 1. The mean GB wall thickness was 7.79 ± 3.59 mm (10.34 malignant and 6.10 in benign, p = 0.001). At a cutoff of 8.5 mm, the sensitivity and specificity of detecting malignancy was 94% and 67%. The mean SUV uptake was 7.46 (benign 4.51, malignant 14.26, p = 0.0102). At a cutoff of 5.95, the sensitivity and specificity of detecting malignancy was 92% and 79%. For 18F-FDG PET, overall sensitivity was 91%, specificity 79%, PPV 77%, NPV 92%, and diagnostic accuracy was 84%., Conclusion: 18F-FDG PET is a reliable method of differentiation between benign and malignant thickening of the gallbladder particularly when wall thickness and SUV value is taken into account.

Objective: Inoperable and metastatic pheochromocytomas and paragangliomas (PPGLs) present a therapeutic challenge with current treatment options being limited to radiolabelled meta-iodo-benzyl-guanidine (MIBG) and systemic chemotherapy. Peptide receptor radionuclide therapy (PRRT) seems to be a promising option for these patients with few studies reporting favourable response. This systematic review was conducted to evaluate the efficacy and safety of PRRT in patients with advanced PPGLs., Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Searches in PubMed, Scopus and Embase were made using relevant keywords and articles up to May 2019 were included. Data on efficacy and toxicity were extracted from the individual articles, and pooled estimates were generated using meta-analysis., Results: Twelve articles consisting of 201 patients with advanced PPGLs were included. Overall, treatment with PRRT achieved an objective response rate of 25% (95% CI: 19%-32%) and a disease control rate of 84% (95% CI: 77%-89%). Clinical and biochemical responses were seen in 61% and 64% of the patients, respectively. Among the PRRTs, similar tumour response rates were noted for 90 Y-yttrium- and 177 Lu-lutetium-based agents. Treatment-related adverse effects were minimal with grade 3/4 neutropenia, thrombocytopenia, lymphopenia and nephrotoxicity observed in 3%, 9%, 11% and 4% of the patients, respectively. Treatment discontinuation was noted in five out of 102 patients., Conclusions: Peptide receptor radionuclide therapy is a safe and efficacious treatment option for advanced PPGLs and may be considered a viable alternative to chemotherapy and I- 131 MIBG., (© 2019 John Wiley & Sons Ltd.)

Objective: Glutathione (GSH) plays an important role in a horde of cellular events that include cell proliferation and apoptosis.The present study describes the radio-synthesis and characterization of gallium-68 ( 68 Ga)-labelled glutathione for its application in radionuclide imaging of cancer., Subject and Methods: The radio-synthesis of radio-complex 68 Ga-GSH was performed by the direct labeling method. The developed radio-complex was subjected to quality control tests. Colon tumors were developed in healthy male Sprague Dawley (S.D) rats by giving subcutaneous injections of dimethylhydrazine (DMH) in order to monitor the uptake of 68 Ga-GSH radio-complex., Results: Gallium-68-labelled glutathione was synthesized with a labeling efficiency of 73.5%±1%. Percentage plasma protein binding and log Po/w values for the radio-complex were found to be 20%-30% and -0.223±0.12, respectively. A significantly higher percentage specific uptake value of newly developed 68 Ga-GSH complex was observed in colon tumor in comparison to soft tissue at 90 minutes post administration thereby exhibiting specificity for cancerous cells, which was also witnessed significantly increased overtime from the ratio of colon tumor uptake to normal colon uptake (P≤0.05)., Conclusion: Therefore, 68 Ga-labelled glutathione can further be exploited for radionuclide imaging and assessment of tumor drug resistance in patients.

Rhenium-188 (Re) is a β, γ emitter and considered a theranostic radionuclide. It is used for bone pain palliation, treatment of unresectable hepatocellular carcinoma, skin keloids, etc. Re perrhenate is eluted from a W/Re generator in large volumes (8-14 ml) of 0.9% normal saline. Concentrating Re to 1-2 ml volume is important for high radiolabelling yield of various Re radiopharmaceuticals, especially when the generator is old. For this, ion exchange column was prepared in-house, and Re was concentrated using silver ion exchange column and QMA cartridge. Re perrhenate eluted in saline was concentrated to 1 ml with more than 99% yield.

Myocardial perfusion imaging (MPI) is one of the most commonly used nuclear medicine imaging modalities for coronary artery disease evaluation and risk stratification. The authors present incidental image findings in a patient who underwent MPI twice because of development of seizures just before the first SPECT-MPI acquisition. The projection images for first MPI done without medication (phenytoin) showed the retention of hepatic tracer activity. After a few days from restarting of phenytoin, the repeat MPI showed complete hepatic clearance of tracer. This case highlights the possible pharmacokinetic interaction between phenytoin intake and Tc-sestamibi, resulting in faster hepatic clearance of the radiotracer.

PET/CT with Ga-labeled prostate-specific membrane antigen (PSMA) is increasingly recognized as the best imaging modality for disease staging and detection of recurrent prostate cancer. Despite its name, PSMA expression has been reported in a number of nonprostatic benign and malignant pathologies. Apparently, angioneogenesis is the mechanism attributed to increased Ga-PSMA uptake at these sites. Here we illustrate the utility of Ga-PSMA in 5 nonprostatic malignancies that could open up new possibilities for diagnostics and theranostic concepts with PSMA labeled radioligands in nonprostate tumor entities.

Purpose: The aim of this study was to evaluate the incremental value of cocktail F-FDG/F-NaF PET/CT over F-FDG PET/CT alone for detection of skeletal metastases in breast cancer patients., Methods: Seventy patients with locally advanced/recurrent breast cancer were prospectively included. All patients underwent whole-body F-FDG PET/CT and cocktail F-FDG/F-NaF PET/CT within a span of 1 week. Both studies were evaluated to detect presence of skeletal/marrow metastases on PET/CT images by 2 nuclear medicine physicians. Clinical and radiological correlation/follow-up was used as criterion standard., Results: Of 70 patients, 50 (71.0%) had locally advanced breast cancer, and 20 had recurrent breast cancer. On patient-wise analysis, both cocktail PET/CT and F-FDG PET/CT identified skeletal/marrow lesions in 23 (32.8%) of 70 patients. In 8 patients (11.4%), only cocktail PET/CT identified skeletal/marrow lesions, whereas F-FDG PET/CT was negative. In the rest of the 39 patients (55.8%), no skeletal/marrow lesion was identified on both scans. Good correlation was noted between cocktail PET/CT and F-FDG PET/CT results (r = 0.785, P < 0.0001). Cocktail PET/CT detected lesions in significantly more number of patients than F-FDG PET/CT alone (P = 0.007). On lesion-wise analysis, cocktail PET/CT detected more number of lesions in 20 patients as compared with F-FDG-PET/CT alone. Both scans detected same number of lesions in the rest of 11 patients with positive findings. A total of 32 additional lesions were identified on cocktail PET/CT imaging as compared with F PET/CT alone (P < 0.0001)., Conclusions: Cocktail F-FDG and F-NaF PET/CT is superior to F-FDG PET/CT alone for the detection of skeletal/marrow metastases in breast cancer. It can be a better alternative to F-FDG PET/CT alone in facilities where both tracers are available.

Objective: Accurate pre-treatment grading and staging of bladder cancer are vital for better therapeutic decision and prognosis. The aim of the present study was to evaluate the correlation between maximum standardized uptake value (SUV max ) calculated during early dynamic and post-diuretic fluorine-18 fludeoxyglucose ( 18 F-FDG) positron emission tomography (PET)/CT studies with grade and pT-stage of bladder cancer., Methods: 39 patients with suspected/proven bladder carcinoma underwent 10-min early dynamic pelvic imaging and delayed post-diuretic whole-body FDG PET/CT imaging. SUV max of the lesions derived from both studies was compared with grade and pT-stage. Relationship of SUV max with grade and pT-stage was analyzed using independent sample t-test and analysis of variance., Results: SUV max of the early dynamic imaging showing tumour perfusion was independent from the SUV max of delayed imaging. High-grade tumours showed higher SUV max than low-grade tumours in the early dynamic imaging (5.4 ± 1.4 vs 4.7 ± 1.6; p-value 0.144) with statistically significant higher value in Stage pT1 tumours (6.8 ± 0.8 vs 5.5 ± 1.2; p-value 0.04). Non-invasive pTa tumours had significantly less SUV max than higher stage tumours during early dynamic imaging [F(4,29) = 6.860, p 0.001]., Conclusion: Early dynamic imaging may have a role in predicting the grade and aggressiveness of the bladder tumours and thus can help in treatment planning and prognostication. Advances in knowledge: Dynamic PET/CT is a limitedly explored imaging technique. This prospective pilot study demonstrates the utility of this modality as a potential adjunct to standard FDG PET/CT imaging in predicting the grade and aggressiveness of the bladder tumours and thus can impact the patient management.

Primary neuroendocrine tumors of the liver are a diagnostic challenge. We present a rare case of primary hepatic neuroendocrine tumor in which Ga-DOTATATE PET/CT imaging played an important role in the diagnosis and follow-up.

ackground: Monitoring disease activity in sarcoidosis remains a clinical challenge as there is no gold standard. Positron emission tomography (PET) imaging is a novel tool to assess the metabolic activity. There is limited data on the role of serial PET scans in monitoring the disease activity., Methods: This is a prospective study of 27 sarcoidosis patients treated with systemic corticosteroids. Patients underwent two serial PET/CT scans: one before initiating therapy and the follow up scan at end of therapy. The metabolic response on PET scan was classified as: (a) complete metabolic response (CMR); (b) partial metabolic response (PMR); (c) stable metabolic disease (SMD); and, (d) progressive metabolic disease (PMD). Patients with either CMR or PMR were classified as PET responders while those with SMD or PMD were considered as PET non-responders. All patients were followed at 3, 6 and 12 months after completion of therapy. Relapse rates and relapse-free survival was compared between the various groups., Results: There was significant decline in the median SUVmax of the mediastinal lymph nodes, peripheral lymph nodes and the lung parenchyma in the follow up PET scan. Eight patients achieved CMR, 6 patients achieved PMR while 13 patients were PET non-responders. There was no difference in the clinical remission rates between the responders and non-responders. However, the relapse rate was significantly higher in non-responders vs. responders (61.5% vs. 14.2%, p=0.018). None of the patients who achieved a CMR relapsed during the study period., Conclusions: Patients with metabolic response on PET scan have significantly fewer relapses as compared to those with no response on PET scan.

Non-invasive characterization of adrenal lesions is a commonly encountered diagnostic challenge. Characteristic clinical and correlative imaging findings may assist in only arriving at a probable diagnosis. Currently, (18)F-FDG PET/CT is considered to provide the most comprehensive imaging information. We here present a case of bilateral adrenal tuberculosis that highlights the need for caution during the interpretation of (18)F-FDG PET/CT and also the need to suggest histopathological correlation., (Copyright © 2016 Elsevier España, S.L.U. and SEMNIM. All rights reserved.)

Purpose: F-fluorothymidine (FLT), unlike FDG, is incorporated exclusively into DNA and is considered a specific marker of cell proliferation. The role of FLT PET/CT scan in differentiating benign from malignant pancreatobiliary tumors is unknown., Patients and Methods: Twenty-five suspected pancreatobiliary tumors on contrast-enhanced CT (CECT) scan in 23 patients were evaluated by FDG PET/CT and FLT PET/CT scans. The histopathology or fine-needle aspiration cytology was considered as criterion standard for the diagnosis. Surgeons were blinded to FLT PET/CT results. Management decision was guided by clinical and CECT scan and FDG PET/CT., Results: Five of 23 patients had metastatic disease on CECT imaging. The remaining 18 underwent exploratory laparotomy. Two of them had synchronous lesions. Histopathology/fine-needle aspiration cytology confirmed malignancy in 17 lesions and benign disease in the remaining 8 lesions. All 8 benign lesions were negative on FLT PET/CT. Seven of the 8 benign lesions were clinically diagnosed as malignancy on CECT and FDG PET/CT. The specificity, positive predictive value, and accuracy were higher for FLT PET/CT (100%, 100%, and 92%) compared with CECT (12.5%, 70.83%, and 72%) and FDG PET/CT (12.50%, 69.57%, and 68%). However, the sensitivity of FLT PET/CT (88.24%) was similar to CECT (100%) and FDG PET/CT (94.12%)., Conclusions: Molecular-based FLT PET/CT is a better imaging than FDG PET/CT in differentiating benign from malignant lesions in the pancreatobiliary region. It has a potential to bring down the incidence of preventable radical resection in suspected pancreatobiliary tumors.

Anti-histidyl (Jo-1) antibodies have been implicated in the pathogenesis of anti-synthetase syndrome (ASS). A case is presented of a 55-year-old male patient presenting with pyrexia of unknown origin and inconclusive routine investigations. (18)F-FDG PET/CT was performed to locate any abnormal focus, which showed increased FDG uptake in the proximal shoulder muscles, as well as lung lesions. Subsequent investigation showed the presence of anti Jo-1 antibody, and diagnosed as an anti-synthetase syndrome. The patient was successfully treated with glucocorticoids and cyclophosphamide, and the response was assessed with symptomatic relief and disappearance of FDG uptake in lung and muscle lesions on post-treatment FDG PET/CT., (Copyright © 2016 Elsevier España, S.L.U. and SEMNIM. All rights reserved.)

The present study is aimed at carrying out a comparative performance evaluation of different types of (68)Ge/(68)Ga generators to identify the best choice for use in (68)Ga-radiopharmacy. Over the 1 year period of evaluation, the elution yields from the CeO2-based and SiO2-based (68)Ge/(68) Ga generators remained almost consistent, in contrast to the sharp decrease observed in the elution yields from TiO2 and SnO2-based generators. The level of (68)Ge impurity in (68)Ga eluates from the CeO2 and SiO2-based (68)Ge/(68)Ga generator was always <10(-3)%, while this level increased from 10(-3)% to 10(-1)% in case of TiO2 and SnO2-based generators. The level of chemical impurities in (68)Ga eluates from CeO2 and SiO2-based (68)Ge/(68)Ga generators was negligibly low (<0.1 ppm) in contrast to the significantly higher level (1-20 ppm) of such impurities in eluates from other two generators. As demonstrated by radiolabeling studies carried out using DOTA-coupled dimeric cyclic RGD peptide derivative (DOTA-RGD2), CeO2-PAN and SiO2-based generators are directly amenable for radiopharmaceutical preparation, whereas the other generators can be only used after post-elution purification of (68)Ga eluates. Clinically relevant dose of (68)Ga-DOTA-RGD2 was prepared in a hospital radiopharmacy for non-invasive visualization of tumors in breast cancer patients using positron emission tomography., (Copyright © 2016 John Wiley & Sons, Ltd.)

Metastatic jugular paraganglioma are rare tumors and account for less than 1% of the cases of head and neck tumors. We report a 40-year-old woman of jugular paraganglioma, presenting with right-sided neck swelling, hearing loss, and pulsatile tinnitus. Contrast-enhanced CT temporal bone revealed a mass in the right jugular foramina and extending inferiorly to internal jugular vein. Ga DOTANOC PET/CT was performed, which revealed somatostatin receptor expressing lesion in the right internal jugular vein and extension into sigmoid sinus and additional metastatic focus in the sacrum.

PET with fluorodeoxyglucose F 18 (FDG)/computed tomography (CT) imaging has significantly improved the management of head and neck cancer. FDG, however, is not tumor-specific and various image interpretation pitfalls may occur because of false-positive and -negative causes of FDG uptake. Routine imaging examination of head and neck malignancies does not yield all of the necessary data, even with the most advanced imaging technique. Specific interventions, such as use of different dynamic maneuvers and pharmacologic interventions, may provide useful information about the lesion. This article reviews the use of special techniques in FDG PET/CT imaging and whole-body FDG PET/CT imaging for evaluation of head and neck cancer., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Hydronephrosis is a common finding in urinary tract outflow obstruction. Chronically obstructed hydronephrotic system may be associated with parenchymal changes. Ultrasound, intravenous urography, micturating cysto-urethrogram and scintigraphy are commonly performed to evaluate the cause of obstruction. In childhood, pelviureteric junction obstruction is a common cause of the hydronephrosis. Hydronephrosis can also be present in horseshoe kidneys due to poor drainage. However, a large sized hydronephrotic cavity may obscure the finding of horseshoe kidney. A case was reported, and it was diagnosed as horseshoe kidney on follow-up renal dynamic scan and confirmed with the help of dimercaptosuccinic acid SPECT/CT., (Copyright © 2015 Elsevier España, S.L.U. and SEMNIM. All rights reserved.)

Aim and Objectives: The study aims to carry out in vivo tracking of stem cells labeled with positron emission tomography (PET) tracer fluorine 18-fluorodeoxyglucose (F-FDG) and find adequate administration methods for these cells in diabetic patients., Material and Methods: Bone marrow aspirate was taken from the iliac crest of patients. Bone marrow mononuclear cells were separated and purified using centrifugation. These cells were then labeled with PET tracer F-FDG. The labeled stem cells were given in a total of 21 type 2 diabetes mellitus patients comprising 3 groups of 7 patients each. Cells were infused either in peripheral intravenous route or through the targeted routes into the superior pancreaticoduodenal artery and the splenic artery respectively. Biodistribution and quantification studies were carried out at 30 and 90 minutes of stem cell infusion., Results: Our results show that targeted approach resulted in homing and retention of stem cells in pancreas as compared with the intravenous route where no discernible homing of stem cells was there. Outside the pancreas, liver and spleen showed intense FDG labeled stem cell accumulation. In the intravenous group, lung fields showed retention of cells in the initial biodistribution study at 30 minutes with significant clearance in the delayed 90 minute image., Conclusions: Infusion into the superior pancreaticoduodenal artery should be a preferred route than into the splenic artery as the former method resulted in better homing and retention of labeled stem cells. Homing is least likely to occur when the intravenous route is used.

For the growth and spread of a tumor beyond 2 mm, angiogenesis plays a crucial role, and association of various integrins with angiogenesis is evidential. The aim of the study was radiolabeling of DOTA-chelated RGD (arginine-glycine-aspartic acid) peptide with (68)Ga for PET imaging in locally advanced breast carcinoma. DOTA-RGD was incubated with (68)GaCl3, eluted in 0.05 m HCl. Elution volume, peptide amount, and reaction pH were studied. Radio-ITLC, gas chromatography, endotoxin, and sterility testing were performed. Serial (n=3) and whole-body (n=2) PET/CT imaging was done on patients post i.v. injection of 111-185 MBq of (68)Ga-DOTA-RGD. Maximum radiolabeling yield was achieved with 3 mL elution volume of 15-20 μg peptide at pH 3.5-4.0 with 10 minutes of incubation at 95°C. Product samples were sterile having 99.5% radiochemical purity with residual ethanol content and endotoxins in injectable limits. Intense radiotracer uptake was noticed in the tumor with SUVmax 15.3 at 45 minutes in serial images. Physiological radiotracer uptake was seen in the liver, spleen, ventricles, and thyroid with excretion through the kidneys. The authors concluded that (68)Ga-DOTA-RGD has the potential for imaging α,vβ3 integrin-expressing tumors.

Purpose: To evaluate the additive value of whole-body F-18 fluoro-deoxyglucose positron emission tomography (FDG PET) as an adjunct to contrast-enhanced computed tomography (CECT) for detecting recurrence following Whipple's resection for periampullary carcinoma and to analyze the prognostic significance of FDG PET-/CECT-based detection of recurrence., Methods: Fifty patients (34 males, 16 females; mean age: 55 ± 11 years) who underwent PET/CECT following resection of periampullary carcinoma were included. The study was duly approved by the institutional ethical committee for retrospective analysis of the data. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of FDG PET/CECT and CECT alone for detection of recurrence were calculated, and the accuracy was compared with ROC analysis. The prognostic factors for survival following recurrence were analyzed by univariate and multivariate methods., Results: PET/CECT indicated recurrence of disease in 26 (52%) patients. The overall mean survival time was 46 months with an overall survival rate of 42%. The sensitivity, specificity, PPV, NPV and accuracy of PET/CECT and CECT for detection of recurrence were 96.1%, 91.6%, 92.6%, 95.6%, 94% and 76.9%, 75%, 76.9%, 75%, 76%, respectively (p = 0.037). Also change in management could have been achieved in 18% of patients based on the PET/CECT results. In univariate analyses, SUVmax >7.3 was the only predictor of poor survival (p < 0.05)., Conclusion: PET/CECT could be used as a one-stop imaging tool for staging and prognostication of recurrent periampullary carcinoma that could result in better patient management.

The present study describes the successful radiolabeling of [99mTcO(-) 4 ] with doxorubicin, and the resultant product was formulated in to a ready-to-label lyophilized single vial kit preparation for convenient use in a routine clinical setting. The radiolabeled preparation of [99mTc]-doxorubicin exhibited a high radiolabeling efficiency of more than 95.0%, serum stability for up to 24 h, and shelf-life of lyophilized cold kits was more than 6 months. Animal imaging data in tumor-bearing mice demonstrated that [99mTc]-doxorubicin accumulated in the tumor site with high target (tumor) to non-target (contra-lateral thigh) ratio (3.2 ± 0.5). The ratio decreased to 1.2 ± 0.6 indicating a good response on follow up imaging performed after 2 weeks of doxorubicin treatment. [99mTc]-doxorubicin scintigraphic data in human volunteers supported the hepato-renal excretion of the radiotracer as reflected by the increased accumulation of the radiotracer as a function of time in intestine, kidneys, and urinary bladder. Further, imaging in patients (very limited number) indicated that the technique may be useful in the detection of active sarcoma and post treatment (surgery/chemotherapy) remission or absence of the disease. The technique, however, needs validation through further preclinical evaluation and imaging in a larger number of patients., (Copyright © 2015 John Wiley & Sons, Ltd.)

Neurolymphomatosis, a rare extranodal lymphoma, may involve the cranial nerves, peripheral nerves, spinal nerve roots, or nerve plexus. F-FDG PET/CT however shows increased FDG uptake in the nerves but is not specific for malignancy. We report a patient with neurolymphomatosis who underwent F-FDG PET/CT and F-fluorothymidine PET/CT where both the scans showed increased tracer uptake in the right sciatic nerve, proven later as neurolymphomatosis on nerve biopsy. Furthermore, the F-FDG avid mediastinal lymph nodes did not show F-fluorothymidine avidity, suggesting an inflammatory etiology.

Malignant melanoma is an aggressive tumor with poor prognosis that can have widespread metastases at presentation. Melanoma is known to undergo neuroendocrine differentiation. We report a case of a 60-year-old woman with malignant melanoma showing a metastatic lesion in the thyroid expressing somatostatin receptors as evident by Ga-DOTANOC PET/CT and metabolically active widespread subcutaneous metastases on F-FDG PET/CT imaging.

Background: Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome, usually caused by small benign mesenchymal tumors. The localization of these tumors is challenging, however, essential for the management. We compared the utility of F-FDG PET/CT and Ga DOTATATE PET/CT to detect the site of primary tumor in patients with suspicion of TIO., Patients and Methods: Retrospective analysis of 6 patients with hypophosphatemic osteomalacia and suspicion of TIO was performed. Ga DOTATATE PET/CT study was performed in all 6 patients to localize the tumor. F-FDG PET/CT was performed in 4 of 6 patients. F-FDG and Ga DOTATATE PET/CT studies were performed within 1 week of each other. Both studies were interpreted blindly without the knowledge of other imaging findings., Results: All patients had symptoms of osteomalacia and hypophosphatemia. All except 1 patient had increased level of fibroblast growth factor 23. The lag time (symptoms to PET diagnosis) ranged from 1.5 to 22 years. In 4 patients, where both studies were performed, F-FDG and Ga DOTATATE PET/CT were able to localize the tumor in 2 and 3 patients. Ga DOTATATE PET/CT detected tumor in 5 (83.3%) of 6 patients., Conclusions: Ga DOTATATE PET/CT performed better than F-FDG PET/CT and is useful in the detection of tumors causing oncogenic osteomalacia. Therefore, in clinically suspected cases of hypophosphatemic osteomalacia, Ga DOTATATE PET/CT may be performed as first-line imaging investigation to avoid delay in the treatment of this devastating but curable disease. However, further studies with large patient population are warranted to validate our data.

Objective: The primary aim of our prospective study was to evaluate the usefulness of dual-phase F-fluoro-deoxy-glucose PET/computed tomography (F-FDG PET/CT) in the characterization of pancreatic masses. The secondary aim was to assess whether delayed imaging revealed any prognostic information., Materials and Methods: Fifty patients with periampullary or pancreatic masses on conventional imaging were included in this study. Early and delayed PET/CT was performed, followed by pathological examination in all patients. PET/CT parameters including uptake pattern, SUVearly, SUVdelayed, lesion to background ratio (L/B), and retention index (RI) were assessed for their ability to differentiate benign from malignant lesions. Patients with malignant lesions were followed up for a median duration of 26 months. The association of 11 variables with survival was analyzed by univariate and multivariate methods., Results: Thirty-one patients had malignant lesions and 19 had benign lesions. The mean SUVearly, L/B, SUVdelayed, and RI between the malignant and benign lesions were statistically significant. The F-FDG uptake pattern of the lesions had higher sensitivity (93.5%) and specificity (100%) compared with RI (cutoff 25.7%) (84 and 37%, respectively) for diagnosing malignancy (P<0.05). In univariate analysis both RI (>18.7%) and tumor size (>2.6 cm) predicted significantly poor survival, whereas in multivariate analysis RI (P=0.04) was the only predictor of poor survival., Conclusion: Dual-phase F-FDG PET/CT is not useful in characterizing pancreatic masses as it cannot differentiate benign from malignant lesions, and focal uptake on early PET imaging is the best indicator of malignancy. A possible benefit in performing a delayed scan is that a high RI (>18.7) can predict poor survival and hence may be useful in treatment planning.

The authors present a 20-year-old patient with clinical suspicion of acute pancreatic infection. PET/CT showed significantly higher uptake of F-FDG alone compared with FDG-labeled autologous leukocytes in peritoneal thickening and omental deposits, with no abnormal pancreatic uptake of either tracer. Further investigation led to a diagnosis of peritoneal tuberculosis.

Background: Contrast enhanced computerized tomography (CECT) is used to determine severity of acute pancreatitis based upon the presence and extent of necrosis. However limitations do exist precluding its applicability in renal failure. Positron emission tomography (PET) imaging for cardiac perfusion shows good uptake of N-13 ammonia ((13)NH3) metabolites in pancreas owing to high perfusion., Aim: To evaluate the role of (13)NH3 PET/CT in acute pancreatitis and compare it with CECT in diagnosing and quantifying pancreatic necrosis., Material and Methods: Patients presenting within 1 week of acute pancreatitis were studied. Static PET images were acquired after intravenous injection of 370-740 MBq of (13)NH3. (13)NH3 PET/CT was followed by CECT in the absence of renal impairment. Maximum standard-uptake-value (SUVmax) of pancreas (P) and liver (L) were taken and their ratio (P/L) was estimated to determine perfusion. Areas within pancreas with no tracer uptake were considered necrotic. These patients were managed as per institutional protocol. Patients undergoing (13)NH3 PET/CT for coronary artery disease were used as controls., Results: 29 patients (72% males) were studied of whom 6 had elevated serum creatinine. (13)NH3 PET/CT was done in all patients along with 9 controls while CECT was carried out after PET/CT in 23 patients. Median levels of SUVmax (P/L) in the controls, uninvolved pancreas and necrotic areas were 1.0 (0.86-1.03), 0.66 (0.50-0.92) and 0.12 (0.07-0.21) respectively (p < 0.001). Necrosis estimation was similar in 22/23 patients without renal failure while in one patient only (13)NH3 PET/CT picked up necrosis (<30%). 5/6 patients with renal failure had necrosis on (13)NH(3) PET/CT which was confirmed on surgery or subsequent CECT after improvement of renal failure., Conclusion: This pilot study is the first in literature to diagnose necrosis in patients with acute pancreatitis using (13)NH3 PET/CT. With minimal additional radiation burden, it is possible to estimate the absolute tissue perfusion as well. With no adverse renal side effects, this can be an alternative to CECT in patients with renal failure giving similar information. It has good agreement with CECT with a good interobserver acceptability., (Copyright © 2014 IAP and EPC. Published by Elsevier B.V. All rights reserved.)

Background and Aim: Early detection and differentiation of malignant from benign pancreatic tumors is very essential as mass-forming pancreatitis is a frequently encountered problem. Positron emission tomography (PET) has a role in establishing the diagnosis of pancreatic carcinoma when the conventional imaging modalities or biopsies are nondiagnostic. In this prospective study, the utility of fluorodeoxyglucose (FDG)-PET/computed tomography (CT) in the characterization of mass-forming lesions of the pancreas was reported., Methods: (18)F-FDG-PET/CT was prospectively performed in 87 patients diagnosed to have periampullary or pancreatic mass. Lesions with focally increased FDG uptake in PET/CT were considered malignant, whereas those with diffuse or no FDG uptake were considered benign. Semiquantitative analysis with maximum standardized uptake value (SUVmax) was also calculated. The PET/CT results were compared with histopathological results in all patients., Results: Based on the FDG uptake pattern, sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for FDG-PET/CT in characterizing the periampullary and pancreatic masses into benign and malignant lesions were 93%, 90%, 95%, 87%, and 92% respectively. Receiver operating characteristics curve analysis of the SUVmax of the lesions yielded a cut-off value of 2.8, with a sensitivity and specificity of 87.5% and 45% respectively., Conclusion: The FDG uptake pattern in PET/CT can differentiate malignant from benign mass-forming lesions of the pancreas with high accuracy and a discrete cut-off value of SUVmax could not be defined for the same as even lesions with pancreatic tuberculosis showed very high FDG uptake. Hence, in patients with a suspicion of malignancy in the pancreas, a focally increase FDG uptake in PET/CT suggests the diagnosis of malignancy., (© 2012 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.)

Background: Of various nuclear medicine techniques, F-18/flourodeoxyglucose (FDG) positron emission tomography (PET) is considered as the best modality for the assessment of viable myocardium (VM). In this study, we compared the diagnostic accuracy of nitrate augmented Tc-99m tetrofosmin gated G-single-photon emission computed tomography (SPECT) with FDG PET., Methods: 54 consecutive cases of angiographically proven CAD with severe LV dysfunction were enrolled in the study. The patients underwent Tc-99m tetrofosmin G-SPECT and FDG PET as per the standard protocols and were compared., Results: SPECT data analysis indicated functional abnormalities in 661/918 myocardial segments. F-18 FDG PET revealed VM in 496/661 segments. The diagnostic accuracy of baseline NAC, postnitrate NAC, baseline AC, and postnitrate AC Tc-99m tetrofosmin SPECT was 84%, 87%, 90%, and 94%, respectively. κ values for NAC baseline, NAC postnitrate, AC baseline, and AC postnitrate Tc-99m tetrofosmin G-SPECT were 0.65, 0.70, 0.77, and 0.85, respectively. Attenuation correction revealed viability additionally in 46 segments which were non-viable on NAC postnitrate study (P < .001). Nitrate augmentation showed viability additionally in 25 segments which were non-viable on AC baseline scan (P = .004). On patient-based analysis FDG PET changes the management only in 13% (7/54) of patients., Conclusions: Nitrate augmented AC Tc-99m tetrofosmin G-SPECT shows excellent (κ = .85) agreement with FDG PET. FDG PET changes management only in 13% of the patients. Tc-99m tetrofosmin G-SPECT being more widely available and cheaper imaging modality can be reliably used to detect VM where FDG PET is not available.

Purpose: Although initial studies have shown the utility of fluorine-18 fluorodeoxyglucose (F-18 FDG) PET in the detection and restaging of recurrent breast carcinoma, scarce literature exists on F-18 FDG PET/computed tomography (CT). This retrospective study was carried out to evaluate the role of F-18-FDG PET/CT in recurrent breast carcinoma and its impact on management., Materials and Methods: Retrospective analysis of data of 111 patients who underwent F-18 FDG PET/CT and were suspected of having recurrent breast carcinoma was carried out. PET/CT imaging was carried out for distant metastases in histologically proven locoregional recurrence in 23 patients, clinically suspicious locoregional recurrence in nine patients, increasing tumour markers in two patients, suspicion of distant metastatic disease in 61 patients or as a part of surveillance in 16 patients. The final diagnosis of recurrence and stage of disease was made after histopathological analysis, correlative imaging and clinical or imaging follow-up of at least 6 months., Results: The final diagnosis of recurrent breast carcinoma was made in 76 patients and no evidence of recurrence was found in the remaining 35 patients. Locoregional disease requiring local radiotherapy or surgery was diagnosed in 14 patients and distant metastatic disease was diagnosed in 62 patients. FDG PET/CT was true positive in 75 patients, false positive in six patients, true negative in 35 patients and false negative in one patient, with a sensitivity, specificity, positive predictive value and a negative predictive value of 98.7, 85.3, 92.5 and 97.2%, respectively. FDG PET/CT also accurately restaged 22/23 patients with proven locoregional recurrence with an accuracy of 95.45%. Of 53 patients suspected of having distant metastatic disease on other imaging modalities, true distant metastatic disease was diagnosed in 36 patients and FDG PET/CT identified true metastatic disease in 35/36 patients, accurately ruling out metastases in the remaining 17 patients, and was false negative in one patient. In addition to confirming distant metastatic disease, it revealed more metastatic sites in 22 patients. Overall, F-18 FDG PET/CT had a major impact on management in 41% of the 103 patients being analysed for a major change in treatment., Conclusion: F-18 FDG PET/CT is a very sensitive and specific imaging tool in detecting and restaging recurrent breast carcinoma. It can be a very useful imaging tool for restaging locoregional recurrences, and as a one-stop shop imaging technique to confirm suspicious metastatic disease on conventional imaging and to define the total burden of disease.

Adrenocortical carcinoma is a rare and aggressive tumour. Inferior vena caval (IVC) involvement by the tumour thrombus is a rare phenomenon, and extension into the right atrium is even more rare. We describe a patient with Cushing's syndrome for whom (18)F-fluorodeoxyglucose (FDG) PET/CT showed FDG avid right adrenal mass with tumour extension to the IVC and right atrium.

Background: The currently available radiopharmaceuticals are not specific for tumor imaging., Purpose: The present study was conducted to radiolabel doxorubicin with Technetium-99m ([99m]Tc) as a scintigraphic marker of high DNA turnover/intercalation in malignant cells., Methods: Labeling was done by direct method and the developed radiotracer was subjected to quality control tests. The blood kinetics, scintigraphy of tumor-bearing mice, and biodistribution were studied after intravenous injection of about 7.4 MBq of [99m]Tc-doxorubicin. The isotime (5 minutes) anterior images were acquired at different time intervals of 1.5, 3, and 4 hours., Results: The labeling efficiency of [99m]Tc-doxorubicin was estimated to be more than 95%. The protein-binding efficiency was greater than 88% and in vitro stability was up to 24 hours. The biodistribution data support the clearance of the radioligand by dual (renal and hepatic) pathways. A semiquantitative data analysis of the anterior images indicated that a focal concentration of the radiotracer was seen in the tumor at 1.5 hours, which persisted in 3-hour and 4-hour images, respectively., Conclusions: This scintigraphic approach, therefore, could be a powerful tool for cancer detection at early stage. The technique, however, needs further validation through animal experimentation and clinical studies.

Introduction: Fluoro-deoxy-glucose (FDG) can be used to visualize inflammation in atherosclerotic plaques in coronary arteries, if myocardial FDG uptake is adequately suppressed. Prolonged fasting for suppressing myocardial FDG uptake is inconsistent. We evaluated the feasibility to consistently suppress myocardial FDG uptake with a low carbohydrate high fat protein permitted (LCHFPP) diet., Materials and Methods: This was a prospective study. 50 patients were included in fasting group (>12 hours fasting) and 60 patients were included into LCHFPP diet. Fasting group had no special dietary preparation. Patients in LCHFPP diet group were asked to consume LCHFPP diet the night before and 4 hours prior to the study. Visual analysis of myocardial FDG uptake was done on maximum intensity projection image. Using CT images for localization, the ability to delineate possible FDG uptake in the left coronary artery was assessed in the corresponding PET image and the studies were classified as "interpretable" or "Not interpretable"., Results: 60 patients (mean age 47 years) from LCHFPP diet group and 50 patients (mean age 49.9 years) from fasting group were included. None of the patients were known diabetics. The mean blood glucose level was 96 mg/dL. Forty-eight patients had consumed LCHFPP diet as per protocol. Twelve had consumed LCHFPP diet only on the night before the study (non-compliant). The average duration of fasting in compliant patients was 5.9 ± 0.9 hours in the diet group and 14.6 hours in fasting group. In LCHFPP diet group, the myocardial FDG uptake was classified as complete suppression in 31; minimal uptake in 15; moderate inhomogenous uptake in 8 and homogenous intense uptake in 6 patients. Fifty-four of the 60 patients had interpretable study. When non-compliant patients were excluded, 84% of the patients had significant FDG uptake suppression and 94% of the studies were classified as interpretable. In the fasting group, complete myocardial suppression of FDG uptake was noticed in 16; minimal in 8; moderate inhomogenous in 15; and homogenous intense in 11 patients. 27 patients (54%) had interpretable study., Conclusion: Consistent and significant myocardial FDG uptake suppression is possible in most patients using LCHFPP diet. The LCHFPP diet, if taken as per protocol, leads to consistent myocardial FDG uptake suppression to allow for adequate evaluation of the left coronary artery inflammation in nearly all the patients. LCHFPP diet is also significantly more efficacious than prolonged (>12 hours) fasting protocol in suppressing myocardial FDG uptake.

We report a 24-year-old woman with corrosive poisoning who was subjected to pertechnetate scintigraphy to evaluate gastric injury. Fusion imaging (SPECT-CT) provided valuable information regarding viability of gastric mucosa, and it helped guide appropriate management.

Introduction: Patients with caustic ingestion may develop esophageal and/or gastric cicatrization., Objective: Scintigraphic assessment of liquid gastric emptying time in patients with caustic ingestion., Materials and Methods: Consecutive patients with caustic-induced esophageal cicatrization attending the gastroenterology clinic of our institute were studied (patients with age >or=60 years, earlier gastric surgery, vagotomy, peptic ulcer disease, diabetes, systemic sclerosis, and those on gastrointestinal motility-altering drugs were excluded). Gastric emptying time was assessed by radionuclide scintigraphy (ingestion of 200 ml mango juice containing of 18.5 MBq 99mTc sulfur colloid after an overnight fast by static imaging in anterior and posterior projections in supine posture at 10 min intervals each for 1 h). A time-activity curve was generated and gastric half-emptying time (GET 1/2) was calculated. Results were compared with GET 1/2 values estimated for normal individuals in our laboratory (mean+/-2 SD). The emptying study protocol for normal individuals was the same as in patients., Results: Twenty patients (males 10) median age 32 years, 16 with acid ingestion and four with alkali ingestion, were studied. No patient had symptoms suggestive of gastric outlet obstruction or gastroparesis. Eight patients had evidence of gastric cicatrization in the form of straightening of the lesser curvature and pulling of incisura and duodenal bulb medially and loss of parallelism between the fundus and left dome of diaphragm. Gastric distensibility was however normal in them. As compared with values for normal controls (25+/-9 min), GET 1/2 was significantly prolonged in the study group as a whole (53.2+/-27.77 min, P=0.000). No significant difference was observed between different age groups, sex, or type of caustic agent consumed. GET 1/2 differed in patients (n=10) with stricture involving lower-third of esophagus (72.2+/-27.67 min) when compared with those (n=10) who had a stricture involving upper and/or middle-third of esophagus (34.3+/-8.02 min, P=0.000). In the former, GET 1/2 was maximally prolonged in patients (n=6) with involvement of the lower esophagus and reduced stomach capacity (84.6+/-27.03 min), followed by patients (n=4) with lower esophageal involvement with normal stomach capacity (53.7+/-17.41 min), but the difference did not reach statistical significance (P=0.078). Patients (n=10) without lower esophageal involvement did not have statistically significant altered GET 1/2 compared with normal controls (P>0.05)., Conclusion: Our results show that patients with caustic ingestion have prolonged liquid gastric emptying even in the absence of any gastric symptoms.