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Background. Positron emission tomography-computed tomography (PET/CT) with 18F-fluorocholine (FCH) is routinely performed in patients with prostate cancer. In this clinical context, foci of FCH uptake in the head or in the neck were considered as incidentalomas, except for those suggestive of multiple bone metastases.

Purpose: To determine when 18F-choline PET/CT can truly identify local recurrence of prostate cancer., Methods: 1031 patients from 3 European centers underwent (18)F-choline PET/CT (FCH PET/CT) for recurrent disease; 131 subjects (12.7%) showed a positive FCH uptake in the prostatic gland or prostatic fossa. Median age was 72 years (range 48-87 years), and the median PSA level at the time of FCH PET/CT scan was 4.41 ng/mL (0.22-18.13 ng/mL). 45 patients (34.4%) had a Gleason score (GS) >7, and the residual subjects had a GS ≤ 7. The assessment of true or false-positive FCH PET/CT findings was made by magnetic resonance imaging (n = 34) and/or biopsy in 75/131 cases. A χ (2) test and a Z Kolmogorov-Smirnov test were used to assess the correlation between clinical variables (age, PSA, GS, type of therapy) and FCH PET/CT findings., Results: FCH PET/CT resulted truly positive (TP) for recurrent disease in the prostatic gland/fossa in 59/75 patients (79%) and falsely positive (FP) in 16 subjects (21%). The median value of PSA at the time of FCH PET/CT scan was higher in TP as compared to FP, although not statistically significant (4.76 vs. 3.04 ng/mL p > 0.05). Similarly, median age, GS categories, and the type of therapy were similar between the two groups (p > 0.05). However, when matching GS categories and PSA values, we found that the number of patients with TP findings were higher in the case of a PSA > 2 ng/mL, independently from the GS (ranging between 74% and 92%). Conversely, FP rate ranged between 50% and 65% in patients with a PSA ≤ 2 ng/mL, especially in the case of GS ≤ 7, whereas FP was around 25% in those with a GS >7 and PSA > 2 ng/mL., Conclusions: FCH PET/CT has a limited role in evaluation of prostatic gland/fossa recurrence, due to the physiological biodistribution of the radiopharmaceutical agent. However, in 70-90% of patients with a PSA >2 ng/mL, independently from GS, a focal FCH uptake is compatible with a true local recurrence.

Unlabelled: The objective of this study was to explore the ability of the initial Gleason score (GS) to predict the rate of detection of recurrent prostate cancer (PCa) with (18)F-choline PET/CT in a large cohort of patients., Methods: Data from 1,000 patients who had undergone (18)F-choline PET/CT because of biochemical evidence of relapse of PCa between 2004 and 2013 were retrieved from databases at 4 centers. Continuous data were compared by the Student t test or ANOVA, and categoric variables were compared by the χ(2) test. Univariable and multivariable analyses were performed by logistic regression., Results: The GS at diagnosis was less than or equal to 6 in 257 patients, 7 in 347 patients, and greater than 7 in 396 patients. The results of 645 PET/CT scans were positive for PCa recurrence. Eighty-one percent of the positive PET/CT results were found in patients with a PSA level of greater than or equal to 2 ng/mL, 43% were found in patients with a PSA level of 1-2 ng/mL, and 31% were found in patients with a PSA level of less than or equal to 1 ng/mL; 78.8% of patients with positive PET/CT results had a GS of greater than 7. The results of (18)F-choline PET/CT scans were negative in 300 patients; 44% had a GS of less than or equal to 6, 35% had a GS of 7, and 17% had a GS of greater than 7. PET/CT results were rated as doubtful in only 5.5% of patients (median PSA, 1.8 ng/mL). When the GS was greater than 7, the rates of detection of (18)F-choline PET/CT were 51%, 65%, and 91% for a PSA level of less than 1 ng/mL, 1-2 ng/mL, and greater than 2 ng/mL, respectively. In univariable and multivariable analyses, both a GS of 7 and a GS of greater than 7 were independent predictors for positive (18)F-choline PET/CT results (odds ratios, 0.226 and 0.330, respectively; P values for both, <0.001)., Conclusion: A high GS at diagnosis is a strong predictive factor for positive (18)F-choline PET/CT scan results for recurrent PCa, even when the PSA level is low (i.e., ≤1 ng/mL)., (© 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.)

Objective: The aim of this study was to evaluate the efficiency of [(18)F]fluorocholine positron emission tomography/computed tomography (FCH PET/CT) in detecting lymph-node and bone involvement in comparison with conventional imaging, such as abdominal-pelvic CT and bone scan, in the initial staging of prostate cancer (PCa)., Materials and Methods: The study retrospectively evaluated 48 patients who had FCH PET/CT for the initial staging of PCa. At the same time, 32 of the 48 patients had a bone scan and 26 of the 48 patients had abdominal-pelvic diagnostic CT. Diagnostic performance of FCH PET/CT, i.e. sensitivity, specificity and accuracy, was evaluated on a per-patient basis for the whole population and then separately on a per-risk classification, and later in comparison with conventional imaging. Histological specimens or follow-up data were used as the standard of reference., Results: The overall accuracy of FCH PET/CT for lymph-node involvement was 83.3%. The sensitivity of FCH was higher in the high-risk subset (83.3%) than in the intermediate-risk group (33.3%), whereas FCH specificity was similar. In comparison with dedicated CT scan, FCH PET/CT showed a higher sensitivity and a similar specificity (46.2% vs 69.2% and 92.3% vs 92.3%, respectively). Moreover, the sensitivity and specificity of PET/CT were higher than those of bone scan (100% vs 90% and 86.4% vs 77.2%, respectively). In contrast with conventional imaging, PET/CT changed the staging of the PCa in 33.3% patients., Conclusions: The efficiency of FCH PET/CT in detecting both bone and lymph-node involvement of PCa at initial staging was found to be higher than that of conventional imaging. Prospective clinical trials are needed to confirm these findings.

We report a case of a 62-year-old man with biochemical recurrence of prostate cancer disease, investigated by fluorine-18-Choline ((18)F-FCH) PET/CT. (18)F-FCH PET/CT demonstrated focal increased uptake of (18)F-FCH inside the right testis, suggestive for distant recurrent disease. On testis removal, a Leydig cell tumor of 2.5 cm in diameter was unexpectedly found. (18)F-FCH PET/CT may demonstrate tumors other than prostate cancer.

A 59-year-old man presented with frequent urination. Six months ago, his prostate-specific antigen (PSA) was 1.56 ng/mL; currently it is 3.5 ng/mL (PSA doubling time = 6 months; PSA velocity = 0.19 ng/mL/mo). Biopsy revealed aggressive prostate cancer (Gleason score 5 + 5). Staging with (18)F-fluorocholine PET/CT ((18)F-FCH PET/CT) demonstrated lymph node metastasis. After 6 months of hormonal therapy with goserelin, PSA decreased to 0.38 ng/mL. A (18)F-FCH PET/CT restaging scan demonstrated a global reduction of (18)F-FCH lesion uptake with disappearance of some mediastinal and iliac pelvic lymph node activity.

Objective: This study aimed to evaluate the efficiency of 18F-FDG PET/CT in suspected recurrence of epithelial ovarian cancer, after treatment, comparing outcomes of PET/CT with histological tumor subtype, CA-125 serum levels, and findings of conventional diagnostic imaging modalities (CI)., Methods: Data from 121 women who underwent FDG PET/CT for suspected recurrence of epithelial ovarian cancer after treatment were reviewed retrospectively., Results: Of all patients, 80% had recurrent disease and 20% were disease-free on the final clinical diagnosis. PET/CT showed true-positive findings in 82% of patients, whereas CI demonstrated true-positives in 70% of cases. At the time of PET/CT scanning, only 55 patients had serum CA-125 level greater than 35 U/mL, whereas 52 patients presented with CA-125 levels in a reference range. PET/CT sensitivity (82%) was significantly higher than that of CA-125 (59%), whereas difference in sensitivity between PET/CT and CI (69%) was limited. PET/CT specificity (87%) was significantly better than that of CI (47%), although no difference in specificity between PET/CT and CA-125 (80%) was found. However, no difference in CA-125 serum levels between patients with local tumor relapse and those with distant metastases was found. PET/CT showed the highest positive predictive value (96%) and negative predictive value (55%) when compared with other modalities. In high-grade tumors (n = 66), PET/CT accuracy was 80%, better than that of serum CA-125 (64%) and that of CI (62%). Equally in low-grade ovarian carcinomas (n = 55), PET/CT accuracy (87%) was significantly higher than that of the tumor marker (60%) and also higher than that of CI (70%)., Conclusions: FDG PET/CT was proven to be more efficient than serum CA-125 assay and CI in detecting recurrences of ovarian cancer after treatment. The sensitivity of FDG PET/CT is not influenced by tumor histology. FDG PET/CT should be considered a useful diagnostic tool in the surveillance of patients that received treatment for epithelial ovarian carcinoma.

Aims and Background: The present study evaluated toxicity, local control, and survival in patients with relapsed high-grade glioma after surgery and external beam radiation therapy and treated with re-operation and GliaSite brachytherapy., Methods: Between 2006 and 2008, 15 patients with recurrent high-grade glioma underwent re-operation and GliaSite brachytherapy. Ten patients were males and 5 females. Median age was 40 years (range, 20-71). Karnofsky performance status was ≥70. All patients but one received GliaSite irradiation of the surgical cavity wall at the dose of 4500 cGy at a depth of 1 cm., Results: No severe acute side effects were observed during GliaSite brachytherapy. Pathologically documented, symptomatic late radiation necrosis was observed in 3 patients (20%); 2 subsequently died of further complications. Two patients were alive at a median follow-up 13 months (range, 1-30). Median overall survival after GliaSite brachytherapy was 13 months., Conclusions: Patients with recurrent high-grade glioma can be treated with additional surgery and GliaSite brachytherapy, delivering 4500 cGy at 1 cm depth without significant acute side effects but with a significant rate (20%) of late radiation necrosis, resulting in 13% of treatment-related deaths. Compared with the literature, survival results in our study appear to be satisfactory, but they may be related to patient selection criteria. Re-intervention followed by GliaSite brachytherapy should not be offered as a standard treatment for recurrent high-grade glioma, because of the high rate of late complications, treatment-related deaths, and high treatment costs.