Combination of hemoglobin,alkaline phosphatase,and age predicts optimal docetaxel regimen for patients with castration-resistant prostate cancer

Background

We aimed to find the prognostic factors predicting overall survival (OS) in patients with castration-resistant prostate cancer (CRPC) who had docetaxel (DTX) chemotherapy, and to construct a model predicting the optimum number of cycles of DTX.

Methods

A total of 279 CRPC patients who received DTX (≥50 mg/m²) every 3–4 weeks were studied retrospectively. Prognostic factors predicting treatment cycles as well as OS were analyzed, and a risk table for predicting treatment cycles was constructed.

Results

The longer treatment group (>10 cycles) had a significantly longer OS than the standard treatment group (p < 0.0001). Multivariate analysis demonstrated that a decrease of ≥50 % in prostate-specific antigen (PSA), serum markers at the start of DTX therapy [PSA, alkaline phosphatase (ALP), and C-reactive protein (CRP)], and the number of DTX courses were independent predictors of OS. The risk table employing the combination of three factors [ALP (cut-off 189 IU/L), hemoglobin (11.3 g/dL), and age (65 years) at the start of DTX therapy], and scoring based on the hazard ratio of each risk factor (ALP 4, hemoglobin 2, age 3) could effectively predict the probability of the length of DTX therapy, with lower score (0–6) predicting >10 cycles, and higher score (7–9) predicting ≤5 cycles (p < 0.0001). No significant difference was found regarding grade 3/4 adverse events between the two groups.

Conclusion

A model using three factors prior to chemotherapy may be beneficial for deciding the duration of DTX therapy in patients with CRPC.