Efficacy of cabazitaxel and the influence of clinical factors on the overall survival of patients with castration-resistant prostate cancer: A local experience of a multicenter retrospective study

Aim To date, the optimal sequencing of life-prolonging therapies for patients with metastatic castration-resistant prostate cancer (mCRPC) remains unclear owing to a lack of prospective trials. This study aimed to evaluate the efficacy and safety of cabazitaxel (CBZ) treatment and examine the prognostic factors for oncological outcomes in patients with mCRPC who received CBZ after docetaxel (DOC). Methods This multi-institutional retrospective study included 44 patients with mCRPC who received CBZ. All enrolled patients had histologically confirmed prostate cancer (PCa) with distant metastases and had received DOC before CBZ administration. The primary endpoint was the oncological outcomes, including the overall (OS) and progression-free survival (PFS). The secondary endpoints were adverse events due to CBZ and rates of >= 30% reduction in prostate-specific antigen (PSA) levels. Results The median follow-up period was 9.2 months (range, 0.2-34 months). During this time, 34 patients (77%) died of PCa. The median OS and PFS were 12.2 (range, 0.2-34 months) and 1.4 months (range, 0.4-17 months), respectively. According to the PSA decline rate, patients who achieved a >= 30% reduction in PSA levels had significantly longer OS than those who showed a <30% reduction in PSA levels (P = 0.002). Regarding the number of cycles of CBZ, patients who received >= 4 cycles of CBZ showed significantly longer OS than those who received <4 cycles of CBZ (P < 0.001). Patients who had visceral metastasis showed significantly shorter OS than those without visceral metastasis (P = 0.012). Conclusion This study demonstrated that CBZ was effective and safe in Japanese local patients in a real-world setting. Patients with mCRPC who received >= 4 cycles of CBZ showed a >= 30% reduction in the serum PSA levels, and did not have visceral metastasis might achieve longer OS.