Androgen deprivation therapy does not impact cause-specific or overall survival in high-risk prostate cancer managed with brachytherapy and supplemental external beam.

Abstract

To determine cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in high-risk prostate cancer patients undergoing brachytherapy with or without supplemental therapies. Between April 1995 and July 2002, 204 patients with high-risk prostate cancer (Gleason score > or = 8 or prostate-specific antigen [PSA] >20 ng/mL or clinical stage > or = T2c) underwent brachytherapy. Median follow-up was 7.0 years. The bPFS was defined by a PSA < or = 0.40 ng/mL after nadir. Multiple clinical, treatment, and dosimetric parameters were evaluated for the impact on survival. The 10-year CSS, bPFS, and OS were 88.9%, 86.6%, and 68.6%, respectively. A statistically significant difference in bPFS was discerned between hormone naive, ADT < or = 6 months, and ADT >6 month cohorts (79.7% vs. 95.% vs. 89.9%, p = 0.032). Androgen deprivation therapy (ADT) did not impact CSS or OS. For bPFS patients, the median posttreatment PSA was <0.04 ng/mL. A Cox linear regression analysis demonstrated that Gleason score was the best predictor of CSS, whereas percent positive biopsies and duration of ADT best predicted for bPFS. The OS was best predicted by Gleason score and diabetes. Thirty-eight patients have died, with 26 of the deaths from cardiovascular/pulmonary disease or second malignancy. Eleven patients have died of metastatic prostate cancer. The ADT improved 10-year bPFS without statistical impact on CSS or OS. Death as a result of cardiovascular/pulmonary disease and second malignancies were more than twice as common as prostate cancer deaths. Strategies to improve cardiovascular health should positively impact OS.