Maximal androgen blockade versus castration alone in patients with metastatic prostate cancer

Objective: Maximum androgen blockade (MAB), consisting of an antiandrogen plus either a luteinizing hormone-releasing hormone agonist (LHRHA) or orchiectomy, is a standard care for patients with prostate cancer. Although, clinical trial results have been equivocal, none has shown a significant advantage in favor of MAB over castration alone in metastatic prostate cancer and MAB has been the subject of considerable controversy. The aim of this study was to compare MAB (orchiectomy or LHRHA “Goserelin”) and anti-androgen “Bicalutamide” with castration alone (orchiectomy or LHRHA) in previ-ously untreated metastatic prostate cancer patients.Methods: Hundred eligible patients with adequate performance status and adequate hematologic, hepatic and renal functions were included. MAB arm, fifty patients underwent castration either surgicaly by orchiectomy or medicaly by receiving Goserelin (3.6 mg) depot, which was injected subcutaneously every 28 days plus bicalutamide 50 mg once daily. Castration alone arm, fifty patients underwent castration alone either surgicaly by orchiectomy or medicaly by receiving Goserelin (3.6 mg) depot.Results: During the period from January 2011 to January 2013, with a median folow up of 18 months (range 6 to 24 months), there were eight deaths (16%), in MAB arm and ten deaths (20%) in castration alone arm. At three months, there were 35 patients (70%) with prostate specific antigen (PSA) normalization (≤ 4 mg/dL) in MAB arm versus 17 patients (34%) with PSA normalization in castration alone arm (P = 0.001). The median progression free survival (PFS) times were 22.18 months (95% CI, 19.7 to 24.2 months) for MAB arm versus 22 months in castration alone arm (95% CI, 18 to 25.9 months;P = 0.045). The survival rates for MAB arm were 82% at 18 months and 70.6% at 24 months versus 78.7% at 18 months and 75.1% at 24 months in castration alone arm (P > 0.05). The median overal survival (OS) was not reached in either arm. Both hematological and non-hematological toxicities were com-parable in both arms.Conclusion: MAB significantly improves the PSA normalization rate at 12 weeks and PFS compared to castration alone with no significant diference in overal survival and with comparable acceptable toxicities. However further studies are needed to document such findings.