Abstract
56 Background: There are no available imaging biomarkers that can prognosticate for clinical outcomes for patients treated with AA. FDG and FDHT PET demonstrate glucose metabolism and androgen receptor expression, respectively. This is the first study of FDG and FDHT PET as a prognostic biomarker for pts treated with AA. Methods: Pts with progressive metastatic castration resistant prostate cancer (mCRPC) starting AA underwent FDG and FDHT PET scans on an imaging clinical trial. PSA, SUVmax (hottest slice of hottest lesion), and SUVmaxavg (average SUVmax of 5 index lesions) were collected. An SUV value of 1 was imputed for calculating SUVmaxavg in the absence of 5 index lesions. Imaging characteristics were compared to PFS, defined as time to radiographic progression, biochemical relapse or death. The Cox proportional hazards model was used to determine the association between the PET measurements and PFS. The statistics used to measure the association was the concordance probability estimate (CPE). Results: 24 scans sets were obtained. Median pt characteristics were: age 70 (48-85), Gleason score 8 (range 6-10), PSA 85 (2-459). Radiographic and PSA progression occurred in 15/24 (63%), radiographic only 4/24 (17%), and biochemical only 2/24 (9%). 1 pt died on study, 1 elected to discontinue tx, and 1 remains on AA. 16/24 (67%) and 18/24 (75%) of FDG and FDHT PET scans respectively had ≥ 5 hypermetabolic lesions. Median FDG SUVmax was 8 (2-15), FDG SUVmaxavg 5 (1-11), FDHT SUVmax 11 (3-28) and FDHT SUVmaxavg 7 (1-16). The correlation between PET measurements and PFS is described (Table). Conclusions: Preliminarily, baseline FDG SUVmax and SUVmaxavg appear to be prognostic for PFS in pts treated with AA. Higher SUV values prognosticate for a shorter time to progression. Further evaluations of FDG/FDHT PET in mCRPC are underway to better define the role each modality has as a prognostic and response biomarker for AA. Clinical trial information: NCT00588185. [Table: see text]
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
