Benign prostatic hyperplasia (BPH) is a very common condition affecting over 800,000 American males each year. A standard, effective, and well-proven therapy is prostatectomy. This surgical procedure is used to treat, in the United States, approximately 400,000 BPH patients annually. Major treatment benefit is expected in 70% to 80% of patients. Complications are seen in 20% of the surgically treated patients. Due to the advanced age of BPH patients and the presence of other serious coexisting medical problems, surgical therapy may be difficult to utilize. These patients, who present a high risk for surgery, are in need of alternative treatments. Alternative therapy in BPH patients with clinically important symptoms and signs of urinary outflow obstruction include treatment with pharmacological agents, balloon dilatation, laser beam therapy, transurethral thermal therapy, transrectal microwave hyperthermia, and transurethral microwave hyperthermia. These alternative treatment modalities are currently under intensive study. These new treatment modalities ultimately must be compared with the standard treatment, which is prostatectomy. Due to the unpredictable natural history of BPH, it is desirable that each Phase III study should contain a no-treatment observation-only arm. Adenocarcinoma of the prostate (CaP) has become a tumor, which first in frequency, and second in importance in cancer mortality statistics of American males. Local tumor control rates and long-term survivals, with radical prostatectomy or radiation therapy, have been excellent. There was, however, recent concern regarding a high incidence of microscopic local tumor recurrence following a definitive course of irradiation. Deep regional or intracavitary hyperthermia (HT) with phase steering may be of value as an adjuvant treatment to radiotherapy. This HT may increase the incidence of local tumor control obtained with radiotherapy. Phase I-II clinical studies are currently underway.