OBJECTIVES: I. Estimate the maximum tolerated dose of weekly intravenous doxorubicin (DOX) that can be given in combination with oral estramustine (EM) in patients with metastatic prostate cancer refractory to treatment with hormonal agents. II. Assess the frequency of expression of the multidrug resistance phenotype in biopsy specimens from these patients. III. Assess the response to DOX/EM in these patients.