[Diagnosis of localized prostate cancer: screening and preoperative staging]

In 712 patients, mapping of the prostate by six systematic ultrasound-guided core biopsies was performed without major side effects using the "biopyt gun". The histologic findings provided data on patients with normal and those with abnormal prostates on digital rectal examination (DRE). Only 3 of 72 (4%) nonurologic patients with normal prostate-specific antigen (PSA; less than 4 ng/ml) had prostate cancer. In patients with firm prostates on DRE and normal PSA, 13 out of 101 (13%) had prostate cancer. In patients in whom PSA was greater than or equal to 4 ng/ml, 92 of 158 (58%) had prostate cancer. In patients with clinical stage B or C and PSA less than 4 ng/ml, 20/56 (36%) had prostate cancer, compared to 155 of 187 (83%) patients with PSA greater than or equal to 4 ng/ml. Transrectal ultrasound (TRUS) seemed not to be useful in screening for prostate cancer, due to its low specificity of 54%, although in patients with clinical stage B or C TRUS identified 157/175 (90%) patients with prostate cancer. For staging prostate cancer we compared in 103 men with pelvic lymph node dissection the value of digital rectal examination, computerized tomography (CT), magnetic resonance imaging (MRI), PAS, TRUS, and random systematic biopsy for identification of lymph-node-positive patients before radical prostatectomy. CT had a sensitivity of only 7% and a specificity of 96% in detecting lymph nodes, whereas MRI had a sensitivity of 50% and a specificity of 100%.(ABSTRACT TRUNCATED AT 250 WORDS)