Feasibility of Tri-Weekly Docetaxel-Based Chemotherapy for Elderly Patients (Age 75 and Older) with Castration-Resistant Prostate Cancer

Objectives: To evaluate the efficacy and safety of docetaxel-based chemotherapy for elderly metastatic castration-resistant prostate cancer (CRPC) patients aged 75 or higher. Methods: Twenty CRPC patients aged 75 or higher (older group) and 31 CRPC patients younger than 75 years (younger group) were treated by a regimen of docetaxel (70 mg/m2) once every 3 weeks. Adjustment for docetaxel dosage and period per cycle was subject to investigator’s judgment. Results: The median relative dose intensity of both groups was 0.84, while the median dose intensity and the number of treatment cycles of the younger and older groups were 14.6 versus 12.3 mg/m2/week (p = 0.021), and 9 versus 8 cycles (p = 0.15), respectively. In the older group, PSA response rate was 50%, median time to biochemical progression was 7.5 months, and median survival time was 15.5 months, without any significant difference compared to those of the younger group. No significant difference in the incidence of grade 3–4 adverse events was noted between both groups. All these parameters for efficacy are comparable to those reported for tri-weekly docetaxel regimen. Conclusions: Tri-weekly treatment by docetaxel (70 mg/m2) with proper adjustment might contribute to maintaining efficacy and safety of the treatment for elderly CRPC patients.