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Objective: To evaluate the role of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ( 18 F-FDG PET/CT) in identifying the cause of fever of unknown origin (FUO) in patients on renal replacement therapy (RRT) for end-stage renal disease (ESRD)., Subjects and Methods: We retrospectively reviewed the 18 F-FDG PET/CT scans of 46 patients with a mean age of 39.28±12.50 years on RRT for ESRD. All patients with abnormal scans had histopathologic examination and microbial cultures of tissue samples from areas with increased standardized uptake value maximum (SUVmax) suggesting the cause of FUO in the 18 F-FDG PET/CT scan. Fluorine-18-FDG PET/CT was considered helpful if it led to the diagnosis of the cause of FUO after histopathologic and microbiologic examinations., Results: Fluorine-18-FDG PET/CT was helpful in identifying the cause of FUO in 22/46 patients (47.83%). Infection was the cause of fever in all these 22 patients. C-reactive protein (CRP) (P=0.003) and procalcitonin levels (P=0.021) were higher in patients with helpful 18 F-FDG PET/CT. No significant difference was found in blood sugar levels and leucocytes counts between patients with helpful 18 F-FDG PET/CT outcome and those without. By multiple regression analysis, the odds of a helpful 18 F-FDG PET/CT increased with every unit increase in CRP level (OR: 1.009; 95% CI: 1.003-1.016; P=0.005)., Conclusion: About half of the 18 F-FDG-PET/CT scans (22/46) identified the cause of FUO in patients on RRT for ESRD. The clinical utility of 18 F-FDG PET/CT in this group of patients is comparable to its average performance in the unselected patients' population evaluated for FUO. A higher CRP level was predictive of a positive 18 F-FDG PET/CT outcome.

Objective: In this study we aimed to present our experience on the use of Gallium-68-dotatate with positron emission tomography, computed tomography ( 68 Ga-dotatate PET/CT) in the management of neuroendocrine tumors (NET) and other somatostatin expressing tumors., Subjects and Methods: We retrospectively reviewed patients with histologically confirmed or biochemically suspected NET and other somatostatin expressing (SSTR) tumors imaged at our department with 68 Ga-dotatate PET/CT. We determined the performance of this imaging technique as well as its impact on patients management. A total of 203 patients were studied: 103 females, 100 males median age 52years., Results: The commonest tumor type was gastroenteropancreatic NET (41% of patients) and the commonest sites of distant metastases were lymph nodes and the liver 34.0% and 30.5% respectively. Positron emission tomography detected foci of disease in 19 patients where CT was falsely negative. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 68 Ga-dotatate PET/CT imaging of NET and other SST expressing tumors were 94.16%, 91.89%, 95.55%, 89.47% and 96.55% respectively., Conclusion: Gallium-68-dotatate PET/CT was better than CT in detecting primary sites of the disease and highly sensitive and specific for diagnosis and treatment of NET and other SSTR expressing tumors.

Objective: Imaging with fluorine-18-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) has, until recently provided disappointing results with low sensitivity ranging from 31%-64% in patients with well-differentiated prostate cancer (PC) at all prostatic specific antigen (PSA) levels while fluorine-18-fluoroethylcholine ((18)F-FECh) PET/CT showed about 85% sensitivity in restaging patients after relapse. We present our experience of the sensitivity of (18)F-FECh PET/CT in the early stages of PC., Subject and Methods: Fifty patients were prospectively recruited and imaged, of which 40 fulfilled all inclusion criteria. Our patients had an average age of 65.5 years. Fifteen patients were referred for initial staging, with the remaining 25 referred for restaging and all patients had histologically confirmed adenocarcinoma. Patients were imaged by (18)F-FECh PET/CT. Findings were evaluated qualitatively and quantitatively and compared to the results of histology, PSA, Gleason score and bone scintigraphy. The prostate SUVmax was also used., Results: Thirty-one patients demonstrated abnormal pelvic- and or extra- pelvic findings on (18)F-FECh PET/CT, which was consistent with malignant or metastatic involvement. The prostate SUVmax could not be used to predict the presence or absence of metastatic disease., Conclusion: Findings of this paper suggest that (18)F-FECh PET/CT in 30/40 cases (estimated as 75%) was helpful in the initial staging, restaging and lymph node detection of patients with PC. The SUVmax was not helpful. We diagnosed more PC cases in our African-American patients as compared to the Caucasian patients.

Our aim was to develop a practical method to prepare 68Ga-citrate using a SnO2-based 68Ge/68Ga generator and evaluate its use in infection imaging. 68Ga-citrate synthesis was performed in a straight forward, quantitative, one-step-aseptic procedure; an amended labeling method was applied using ACD-A buffered citrate as a precursor. Study participants were imaged on a Siemens Biograph 40 PET/CT scanner 60 min post intravenous injection. Our results showed: 90%-95% 68Ga-yield was obtained and subsequently used at 324-527 MBq to perform three to four parallel 68Ga-citrate syntheses. 68Ga-citrate of 96%-99% was yielded after 10 min incubation. The radiochemical purity was >99% with a pH value of 4.0-4.5. All other quality control requirements were met. The 68Ga-citrate stability was >96%. The final product was sterile, pyrogen and solvent-free, with very low 68Ge-levels, with 191±33 MBq in 6.6±2.8 mL. High quality images were obtained at 60 min post injection of 185 MBq of 68Ga-citrate. In conclusion, a fast, direct and cheap method with a quantitative preparation of 68Ga-citrate was described. We reported on the adaptations needed when using a SnO2-based 68Ge/68Ga generator and ACD-A buffered citrate as a precursor. This method allowed for multiple patient productions from one generator elution, with 300 MBq/patient of 68Ga-citrate produced in less than 30 min and excellent labeling reproducibility for routine infection imaging.