Page 3 - CUA2018 Abstracts - Oncology-Prostate

Podium session 1: Prostate Cancer

Marsden Hospital, London, United Kingdom; St. Vincent’s Hospital, multimodality agreement. SRT response was defined as a PSA drop of
9
Sydney, Australia >50% without androgen–deprivaton therapy (ADT).
Introduction: A significant proportion of men will not benefit from salvage Results: Median PSA at imaging was 0.4±1.2, median Gleason score
radiotherapy (SRT) after radical prostatectomy (RP). This study aims to was 8, and median PSA doubling time was five months. Detection rates
evaluate the predictive value of new imaging methods, such as fluoro- for any recurrent prosate cancer were 27% (24/89), 32% (29/90), and
methylcholine (FCH) and prostate–specific membrane antigen ligand– 43% (13/30) for mpMRI, FCH, and PSMA, respectively. In these, extra-
positron–emission tomography/computed tomography (PSMA–PET/CT), prostatic bed disease was identified in 41% (11/24) (mpMRI), 58% (17/29)
or multiparametric magnetic resonance imaging (mpMRI) in triaging men (FCH), and 69% (9/13) (PSMA); prostatic bed disease was found in 15%
unlikely to benefit from SRT. (mpMRI), 13% (FCH), and 13% (PSMA). Imaging findings changed man-
Methods: This study is a prospective trial in men post–RP with poor agement in 46% for FCH and 24% for MRI. An incremental management
response features (prostate–specific antigen [PSA] >0.2 ng/ml and impact of PSMA over FCH was identified in 27% (8/30). Among men with
>Gleason 7 or PSA doubling time (DT) <10 months, or PSA >1.0 ng/ml) negative or fossa–confined PSMA or FCH, treatment response to prostate
with a rising PSA and being considered for SRT after negative conventional bed SRT was 78% (7/9) and 72% (33/46), respectively.
imaging. Ninety eligible men underwent FCH PET/CT, mp–MRI within two Conclusions: PSMA or choline PET/CT detected most extraprostatic dis-
weeks, with a subset of men (30) undergoing an additional PSMA PET/CT. ease in men with rising PSA post–RP being considered for SRT with
Imaging was double–read with consensus. There was documentation of poor response features. The findings had a significant impact on patient
the treatment plan before and after imaging to assess management impact. management and treatment outcomes.
Imaging results were validated using a composite reference standard of
biopsy, repeat imaging, PSA response to targeted treatment, and complete

CUAJ • June 2018 • Volume 12(6Suppl2) S53