ADDITION OF DOCETAXEL TO EARLY HIGH RISK PROSTATE CANCER

As reported in the Journal of Clinical Oncology by Rosenthal et al, the phase III NRG Oncology RTOG 0521 trial showed that the addition of docetaxel to androgen suppression and radiotherapy improved overall and disease-free survival as well as the distant metastasis rate in patients with high-risk localized prostate cancer.

In the study, 563 patients were randomly assigned between December 2005 and August 2009 to receive either: androgen suppression for 8 weeks, followed by external-beam radiation therapy to 72.0 to 75.6 Gy with concurrent androgen suppression, followed by adjuvant androgen suppression for a total of 24 months (AS + RT group, n = 281); or the same treatment plus 6 cycles of chemotherapy with docetaxel and prednisone concurrently with androgen suppression beginning 28 days after completion of radiotherapy (AS + RT + CT group, n = 282). The primary endpoint was overall survival.

Key Outcomes

The median follow-up was 5.7 years. Overall survival at 4 years was 93% in the AS + RT + CT group vs 89% in the AS + RT group (hazard ratio [HR] = 0.69, P = .034).

Fewer prostate cancer–specific deaths occurred in the AS + RT + CT group (16 vs 23). Rates of distant metastases at 6 years were 9.1% vs 14.0% (HR = 0.60, P = .044). Disease-free survival at 6 years was 65% vs 55% (HR = 0.76, P = .043).

Adverse Events

Grade 3 and grade 4 adverse events considered at least possibly related to treatment occurred in 37.9% and 25.9% of the AS + RT + CT group vs 20.6% and 1.4% in the AS + RT group, with the difference reflecting higher rates of grade 3 (22.0% vs 1.8%) and grade 4 (22.3% vs 0%) hematologic toxicity in the AS + RT + CT group.

The investigators concluded, “For patients with high-risk nonmetastatic prostate cancer, chemotherapy with docetaxel improved [overall survival] from 89% to 93% at 4 years, with improved disease-free survival and reduction in the rate of distant metastasis. The trial suggests that docetaxel chemotherapy may be an option to be discussed with selected men with high-risk prostate cancer.”