Background and purpose: Several recent randomized controlled trials (RCTs) in non-metastatic castration resistant prostate cancer (nmCRPC) have demonstrated a significant improvement in metastasis-free survival (MFS); however, an improvement in overall survival (OS) is not reported yet. Since the surrogacy of MFS to OS has not been formally investigated in nmCRPC in Japan, this study evaluated the correlation between MFS and OS among a nmCRPC population in Japan. Methods: This is a retrospective longitudinal observational cohort study in patients with nmCRPC using the Japanese Medical Data Vision (MDV) database covering over 20 million patients. A total of 1236 patients with CRPC who had no prior medical history of cancer except prostate cancer and no distant metastasis, and who fulfilled PCWG2 criteria, were identified. Following the identification of nmCRPC, patients' medical records were investigated for subsequent events of metastasis and death. Results: The median follow-up time was 24 months. Median MFS was 28 months (95% CI: 24.0 to 33.0 months) and median OS could not be estimated (95% CI: not estimated). There was a statistically significant correlation between MFS and OS (Pearson's correlation coefficient = 0.62; 95% CI: 0.58-0.65; p
It is of much interest to understand the efficacy of abiraterone acetate (AA) in routine clinical practice. We assessed the clinical outcome of AA in patients with metastatic castration-resistant prostate cancer (mCRPC) and determined clinical factors associated with AA treatment duration in real-world setting. This real-world cohort consisted of 93 patients with mCRPC treated with AA in Thailand (58.1%) and Malaysia (41.9%). Primary endpoints were overall survival (OS) and biochemical progression-free survival (bPFS). Secondary endpoints were predictors associated with AA treatment duration evaluated with Cox proportional hazards regression. Around 74% were chemotherapy-naïve. The median AA treatment duration was 10 months (IQR 5.6-17.1). Malaysians had a relatively lower median OS and bPFS (OS 17.8 months; 95% CI 6.4-29.1, bPFS 10.4 months; 95% CI 8.8-12.0) compared to Thais (OS 27.0 months; 95% CI 11.3-42.7, bPFS 14.0 months; 95% CI 5.8-22.2), although it did not achieve statistical significance (P > .05). Patients with longer AA treatment duration (>10 months) had lower risk of death and longer bPFS, compared to those with shorter AA treatment duration (≤10 months) (hazard ratio [HR] 0.10, 95% CI 0.05-0.22 and HR 0.13, 95% CI 0.06-0.25, respectively). Multivariable analysis showed that PSA at AA initiation, presence of PSA response and chemotherapy-naive were independently associated with AA duration (P