What is the real impact of bone pain on survival in patients with metastatic hormone-refractory prostate cancer treated with docetaxel?

OBJECTIVES: To determine the benefit of starting early chemotherapy with docetaxel (the recommended first-line treatment) for patients with asymptomatic metastatic hormone-refractory prostate cancer (HRPC). PATIENTS AND METHODS: Data were analysed from 145 patients with HRPC treated with chemotherapy between February 2000 and June 2002 in one French centre. Eligible patients were categorized into three groups according to the bone pain at baseline, i.e. minimal/no pain, mild, and moderate/severe pain. The primary endpoint was the effect of bone pain on overall survival (OS). RESULTS: Docetaxel was administered to 67% of patients. The risk of death was 1.56 and 2.11 times higher for patients with mild or moderate/severe pain than for those with minimal/no pain (P = 0.027). The median (95% confidence interval (CI)) OS was 23.1 (18.5-27.6) and 14.1 (8.9-19.2) months (P = 0.001, log-rank-test) for patients with minimal pain or no pain treated with docetaxel-based chemotherapy compared with mitoxantrone, respectively. The prostate-specific antigen doubling time (PSA-DT) had a significant effect on OS in patients with minimal/no pain, with a median of 32.4 and 16.5 months for a PSA-DT of >or=45 and <45 days, respectively (P < 0.001). CONCLUSIONS: Our results suggest that patients with HRPC and minimal or no bone pain could have better survival than those with mild pain or moderate to severe pain, independent of the treatment administered. In addition, patients with HRPC and minimal or no bone pain treated with docetaxel-based chemotherapy have a significantly better OS than those treated with mitoxantrone. The PSA-DT can be useful to identify asymptomatic patients who are candidates for early treatment.