DISEASE CHARACTERISTICS: Histologically confirmed metastatic hormone-refractory prostate cancer Castrate serum testosterone less than 30 ng/dL after antiandrogen withdrawal Progressing disease 50% increase in PSA level from the nadir PSA level confirmed twice and measured at least 2 weeks apart OR New bone pain or new lesion on bone scan OR Progression of soft tissue disease by CT or MRI Limited bone disease No more than 3 metastatic sites on bone scan and minimal symptoms No brain metastases