Nilutamide as second line hormone therapy for prostate cancer after androgen ablation fails.

OBJECTIVE

We investigate the prostate specific antigen (PSA) response rate with nilutamide as a second line hormonal agent in patients with advanced prostate cancer in whom androgen ablation failed.

METHODS

From 1998 to 2001, 28 patients with hormone resistant prostate cancer were treated with nilutamide as second line hormonal therapy. Average patient age +/- SD was 72.9 +/- 9.1 years. Median time from diagnosis of cancer to hormone failure was 48 months (range 2 to 120). Median followup from initiation of nilutamide therapy was 26 months (range 15 to 44). All patients had previously received at least 1 antiandrogen (flutamide or bicalutamide) in addition to medical or surgical castration, which failed.

RESULTS

Upon initiation of nilutamide therapy 18 of the 28 patients (64%) had an initial reduction in PSA and 8 (29%) sustained a PSA response (greater than 50% decrease) beyond 3 months (range 3 to 21). PSA response to nilutamide in patients with a previous antiandrogen withdrawal response versus nonresponse was 100% and 18%, respectively. In 10 of the 28 patients, (36%) PSA continued to increase. Interstitial pneumonitis developed, in 1 patient and 5 had nonspecific complaints (headaches, nausea, dizziness). During followup 6 of the 28 patients died 1 of whom was a nilutamide responder. No patient died while on nilutamide.

CONCLUSIONS

Nilutamide can achieve a significant sustained PSA response with a favorable toxicity profile. Patients with a previous antiandrogen withdrawal response have a significantly greater chance of responding to nilutamide.