CHEMOTHERAPY AND CASTRATE RESISTANT PROSTATE CANCER

Chemotherapy Does Not Delay Appearance of Castrate-Resistant Prostate Cancer

NEW YORK (Reuters Health) Dec 12 - In men receiving androgen ablation for advanced prostate cancer, the emergence of castrate-resistant disease is not delayed by three cycles of systemic chemotherapy, according to a report in the Journal of Clinical Oncology published ahead of print on November 24th.

"Do not assume that taxotere or any other chemotherapy works in androgen dependent disease," Dr. Randall E. Millikan advised in comments to Reuters Health.

Dr. Millikan from the University of Texas M. D. Anderson Cancer Center, Houston, and colleagues conducted a phase 3 trial in patients with previously untreated metastatic prostate cancer to test the hypothesis that three 8-week cycles of ketoconazole and doxorubicin alternating with vinblastine and estramustine, given in addition to standard androgen deprivation, would delay the appearance of castrate-resistant disease.

Overall, median time to castrate-resistant progression did not differ significantly between the androgen ablation arm (24 months) and the chemohormonal therapy arm (35 months), the researchers report.

Median overall survival was similar for patients in the control arm (5.4 years) and in the chemotherapy arm (6.1 years), the report indicates.

Just over half the patients exposed to chemotherapy had at least one grade 3 adverse event (most of them attributed to treatment), compared with only 9% of the patients in the androgen-ablation control group (with most events considered unrelated to treatment).

"For the present," the authors conclude, "it is remarkable that more than half a century after its introduction, androgen suppression remains the preferred front-line approach to the treatment of metastatic prostate cancer, and that so far, there is no cytotoxic regimen with clinically relevant activity against hormone-sensitive prostate cancer."

Dr. Millikan added, "We have many phase 2 studies of novel approaches for these patients -- tyrosine kinase inhibitors, immune based therapy, therapy aimed at other growth-stimulating pathways, etc."