Time from definitive therapy for localized prostate cancer to the start of androgen deprivation therapy (ADT) independently predicts the risk of metastatic castration-resistant prostate cancer (mCRPC) and death, a new study suggests.
The study, led by Neeraj Agarwal, MD, of the Huntsman Cancer Institute at the University of Utah in Salt Lake City, included 253 men with newly diagnosed metastatic hormone-sensitive prostate cancer (mHSPC), of whom 115 (45%) received prior definitive therapy (DT) for localized prostate cancer. Prior DT was associated with longer time to mCRPC (24 vs 13.8 months) and overall survival (117.5 vs 45.6 months).
In the DT group, each additional year from DT to the start of ADT was significantly associated with a 9% decreased risk of mCPRC and 13% decreased risk of death on multivariate analysis that adjusted for Gleason score, PSA, race, and other possible confounders, the investigators reported in Urologic Oncology.
In addition, compared with men who had 5 or more years between DT and ADT initiation, those with less than 5 years between those events had a nearly 1.8-fold higher risk of mCRPC.
“If this hypothesis-generating data can be validated independently, time to DT to the start of ADT for new mHSPC may assist with risk stratification and systemic therapy selection in these men,” Dr Agarwal’s team concluded.
As a result of its multi-institutional design, the study was limited by potential patient selection and treatment selection bias, the investigators stated. Moreover, they noted that their limited cohort size prevented them from performing a subgroup analysis by type of DT or volume of disease.
Hahn AW, Stenehjem DD, Alex AB, et al. Time from definitive therapy to onset of metastatic disease predicts outcomes in men with metastatic hormone sensitive prostate cancer. Urol Oncol. 2019; published online ahead of print.