A phase II trial of chemotherapy plus hormone therapy as initial treatment of unresectable/metastatic adenocarcinoma of the prostate.

Abstract

247 Background: Chemotherapy for hormone-refractory prostate cancer reduces PSA levels and enhances overall survival (OS), suggesting that administration in earlier disease stages may be beneficial. If expansion of an androgen-independent clone is present during androgen deprivation mediates the transformation from an androgen-dependent to an androgen-independent phenotype, combination chemohormonal therapy could be effective initial treatment for locally advanced or metastatic prostate cancer. This study examined the efficacy and safety of chemohormal therapy approach. Methods: Patients received medical castration plus an anti-androgen and chemotherapy (nab-paclitaxel, leuprolide, bicalutamide). Patients were followed with PSA levels and radiographic assessments. Results: Forty-six men (median age) 64.7 years were treated. Fifty-eight percent underwent prior local therapy including prostatectomy (30%), prior radiation (15%), or both (13%). Median baseline PSA was 8.9 ng/ml, and 96% of patients had a Gleason score of ≥7%. At 2 years, 78% of patients experienced tumor regression with a median reduction in PSA level of >90%. Median time to progression was 28.43 months measured by PSA and 34.52 months measured radiographically. Median OS was 62.4 months. The most frequent significant adverse events included grade 3 hypokalemia (17%) and lymphopenia (59%). Conclusions: Combination chemohormonal therapy for locally advanced and metastatic prostate cancer delayed disease progression and enhanced OS. Information presented will include curves and correlation detailing efficacy and adverse events of various sub-populations.