BACKGROUND: The role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in prostate cancer (PCa) has not been well defined yet.
Because high-grade PCa tends to exhibit increased glycolytic rate, FDG-PET/CT could be useful in this setting. The aim of this study was to assess the value of FDG-PET/CT for pre-operative staging and prognostic stratification of patients with high-grade PCa at biopsy.
METHODS: Fifty-four patients with a Gleason sum ≥8 PCa at biopsy underwent FDG-PET/CT as part of the staging workup. Thirty-nine patients underwent radical prostatectomy (RP) and pelvic lymph node (LN) dissection, 2 underwent LN dissection only, and 13 underwent non-surgical treatments. FDG-PET/CT findings from clinical reports, blinded reading and quantitative analysis were correlated with clinico-pathological characteristics at RP.
RESULTS: Suspicious foci of increased FDG uptake were found in the prostate, LNs and bones in 44, 13 and 6% of patients, respectively. Higher clinical stage, post-RP Gleason sum and pattern, and percentage of cancer involvement within the prostate were significantly associated with the presence of intraprostatic FDG uptake (IPFU) (P < 0.05 in all cases). Patients without IPFU who underwent RP were downgraded to Gleason ≤ 7 in 84.6% of cases, as compared to 30.8% when IPFU was reported (P = 0.003). Qualitative and quantitative IPFU were significantly positively correlated with post-RP Gleason pattern and sum, and pathological T stage. Absence and presence of IPFU were associated with a median 5-year cancer-free survival probability of 70.2 and 26.9% (P = 0.0097), respectively, using the CAPRA-S prognostic tool.
CONCLUSION: These results suggest that, among patients with a high-grade PCa at biopsy, FDG-PET/CT could improve pre-treatment prognostic stratification by predicting primary PCa pathological grade and survival probability following RP.
Beauregard JM, Blouin AC, Fradet V, Caron A, Fradet Y, Lemay C, Lacombe L, Dujardin T, Tiguert R, Rimac G, Bouchard F, Pouliot F. Are you the author?
Institution(s): See publishing journal.
Reference: Cancer Imaging. 2015 Mar 3;15(1):2.