Value or Transrectal Ultrasonography in the Detection of Occult Prostate Cancer

Sung, Luck Hee; Chung, Jae Yeng; Noh, Choong Hee

Abstract

Historically, digital rectal examination (DRE) had been the only method available to evaluate the prostate gland for malignant tumor. Recently, serum prostate specific antigen (PSA), transrectal ultrasonography (TRUS) and magnetic resonance imaging (MRI) using endorectal coil have been added to the methods used to detect prostate cancer. But the roles of these tests in detecting cancer are currently undefined. Because of its low specificity, some reports have suggested the routine use of TRUS be discouraged. The present study was undertaken to evaluate the value of TRUS in the detection of prostate cancer. In a retrospective study, 123 BPH patients were examined by TRUS and PSA measurement. All patients were planned for prostatectomy and they had no evidence for prostate cancer at DRE. Of 123 patients with pathologically proven diagnosis, 10 patients had prostate cancer and 113 patients had BPH. Among the patients with prostate cancer, 6 patients had elevated PSA level ( >10ng/mL), while a patient had normal PSA level. Of 66 patients whose PSA levels were between 4 and 10ng/mL, only 3 patients had prostate cancer. Among 10 patients with prostate cancer, one patient had positive finding in TRUS, while 9 patients had negative finding. Among 113 patients with BPH, 17 patients had positive findings in TRUS and 96 patients had negative findings. Over all TRUS sensitivity and specificity for prostate cancer detection was 10% and 84.9% respectively. From our data we conclude; 1. The use of TRUS in BPH patients with negative DRE and PSA less than 10ng/mL seems to be questionable. 2. For the patients with negative DRE and PSA higher than 10ng/mL, sono-guided biopsy should be done regardless of the result of TRUS.