Recent docetaxel studies establish a new standard of care in hormone refractory prostate cancer

Treatment of hormone refractory prostate cancer (HRPC) has generally aimed at increasing symptom free survival in asymptomatic patients and improving quality of life in symptomatic patients. However, recent randomized studies might be shifting the paradigm towards achieving an improved overall survival.

Two large randomized controlled studies were conducted using mitoxantrone plus prednisone as a control arm compared to docetaxel-based regimens.

In the TAX 327 trial, 3-weekly docetaxel plus prednisone proved significantly superior to mitoxantrone plus prednisone (an established reference regimen) in extending survival, reducing levels of prostate specific antigen (PSA), controlling pain and improving quality of life. The Southwest Oncology Group's study (protocol 99-16) randomized patients to either docetaxel plus estramustine or mitoxantrone plus prednisone. Compared with the mitoxantrone regimen, docetaxel plus estramustine significantly extended median overall survival and time to progression. Men treated with the docetaxel regimen were also more likely to have a PSA response. In this study, the two regimens were similarly effective in relieving pain.

These studies have an important impact on the management strategy of hormone refractory prostate cancer. Docetaxel is the first agent shown significantly to extend survival in HRPC. Although this proven benefit must be balanced against toxicity, docetaxel should now be considered the standard of care for most patients that fail first-line or more hormonal manipulations. Drug combinations which may further extend survival and improve quality of life are actively being pursued, as is the possibility of using docetaxel in the adjuvant setting.