Cancer Research Lab

The survival of patients with hormone-resistant prostate cancer is significantly longer after treatment with docetaxel every 3 weeks with prednisone (D3P) compared with other regimens, according to the follow-up of a major study.

The update of the TAX 327 study, which compared D3P to a weekly docetaxel treatment with prednisone (D1P) and with mitoxantrone plus prednisone (MP), was published in the January 10 issue of the Journal of Clinical Oncology.

TAX 327 enrolled 1,006 patients from 24 countries between March 2000 and June 2002. When the original analysis was done in August 2003, 557 deaths had occurred. The D3P arm was found have a median survival time of 18.9 months, versus 17.4 months for the D1P arm and 16.5 months for the MP arm (P = 0.009 for D3P versus MP).

Updated median survival times were 19.2 months for the D3P arm, 17.8 months for the D1P arm and 16.3 months for the MP arm. The p value for D3P versus MP, 0.004, was slightly stronger than in the earlier analysis. Similar trends were seen in subgroup analysis between patients older and younger than the median age of 68.

“The docetaxel every 3 weeks regimen was very well tolerated in this elderly patient population,” Dr. Ronald de Wit, of the Erasmus University Medical Center, Rotterdam, The Netherlands, said. “The most uncomfortable side effects are hair loss and fatigue.”

The incidence of serious toxicity in all courses of treatment was less than 5%, with the exception of neutropenia, Dr. de Wit said.

The researchers concluded that “docetaxel administered every 3 weeks with prednisone remains the preferred treatment option for most patients with metastatic hormone-resistant prostate cancer. The consistency of results among subgroups indicates rigorous data.”

As clear as these results are, they are likely somewhat understated, Dr. de Wit said. “Since docetaxel was commercially available (for other indications, such as breast cancer), up to 30% of patients crossed over to docetaxel after they had disease progression on mitoxantrone, and even despite the confounding effect by this frequent cross-over to the superior treatment, a significant benefit in the docetaxel q3 weekly arm was obtained.”