Docetaxel Followed by Hormone Therapy in Men Experiencing Increasing Prostate-Specific Antigen After Primary Local Treatments for Prostate Cancer

Abstract

Purpose: Prostatectomy or radiation for localized prostate cancer (PC) can fail in up to 15% to 30% of patients. The purpose of this study was to determine feasibility, tolerability, and outcome of docetaxel followed by hormone therapy in men experiencing an increasing prostate-specific antigen (PSA) after their primary local treatments for PC. Patients and Methods: Men with increasing serum PSA after prostatectomy or/and radiation were eligible. Serum PSA had to be ≥ 4 ng/mL and serum testosterone had to be in the noncastrate range. Treatment included docetaxel 70 mg/m² every 3 weeks for up to six cycles, followed by total androgen suppression (luteinizing hormone-releasing hormone agonist plus bicalutamide) and peripheral androgen blockade (finasteride plus bicalutamide) for 12 to 20 months. Results: Thirty-nine men were enrolled; 32 had PSA-only failure, seven also had clinical metastasis. Baseline median PSA was 13.7 ng/mL. Serum PSA decreased ≥ 50% in 17 of 35 patients (48.5%) and ≥ 75% in seven of 35 patients (20%) with docetaxel. The PSA decreased to a median of 0.1 ng/mL with subsequent hormone therapy. In 28 of 33 patients the PSA increased (median, 0.41 ng/mL) at a median follow-up of 2.3 months after treatment. In contrast, in five of 33 men the PSA remains at 0.1 ng/mL at a median of 18.9 months after therapy; three of these five men had soft tissue metastasis at entry but remain in complete remission. The most common grade 3 to 4 toxicity was neutropenia (61.5%). Conclusion: Docetaxel followed by hormone therapy of limited duration may provide disease control in subgroups of men experiencing failure after local treatments for PC.