Sequential Therapy with Docetaxel and Cabazitaxel Starting at Low PSA Levels was Associated with Longer Survival in Patients with Castration-Resistant Prostate Cancer

<jats:title>Abstract</jats:title> <jats:p><jats:bold>Background:</jats:bold> This study investigated the optimal timing for starting docetaxel (DOC) and cabazitaxel (CBZ) by examining the correlation of their efficacy and evaluating factors associated with the prognosis of patients with castration-resistant prostate cancer (CRPC) receiving DOC-CBZ sequential treatment.<jats:bold>Methods:</jats:bold> We retrospectively evaluated data for 146 patients who received DOC followed by CBZ. The correlations of prostate specific antigen (PSA) decrease rate and time to progression between DOC and CBZ treatment were examined. The association of parameters with progression-free survival (PFS) and overall survival (OS) were evaluated. Survival rates were compared between patients with high and low PSA levels at the start of DOC and CBZ treatment.<jats:bold>Results:</jats:bold> No correlations of PSA decrease rate and time to progression were observed between DOC and CBZ. In multivariate analyses, higher PSA level at the start of DOC was significantly associated with shorter PFS (<jats:italic>P</jats:italic> = 0.004) and OS (<jats:italic>P</jats:italic> = 0.001). The OS of patients who started DOC and CBZ at low PSA levels was significantly longer than those that started at high PSA levels (<jats:italic>P</jats:italic> = 0.002 and <jats:italic>P</jats:italic> = 0.003). In patients who started DOC at high PSA levels, those who switched to CBZ at low PSA levels had longer OS than those who switched at high PSA levels (<jats:italic>P</jats:italic> = 0.048).<jats:bold>Conclusions:</jats:bold> For patients for whom DOC was not effective, sequential CBZ might reduce PSA for a long duration. Starting DOC and switching to CBZ at low PSA levels might result in improved prognoses in CRPC patients.<jats:bold>Trial registration:</jats:bold> This study was registered retrospectively.</jats:p>