To compare the efficacy of digital rectal examination and serum prostate specific antigen (PSA) in the early detection of prostate cancer, we conducted a prospective clinical trial at 6 university centers of 6,630 male volunteers 50 years old or older who underwent PSA determination (Hybritech Tandom-E or Tandem-R assays) and digital rectal examination. Quadrant biopsies were performed if the PSA level was greater than 4 μg./l. or digital rectal examination was suspicious, even if transrectal ultrasonography revealed no areas suspicious for cancer. The results showed that 15% of the men had a PSA level of greater than 4 μg./l., 15% had a suspicious digital rectal examination and 26% had suspicious findings on either or both tests. Of 1,167 biopsies performed cancer was detected in 264. PSA detected significantly more tumors (82%, 216 of 264 cancers) than digital rectal examination (55%, 146 of 264, p = 0.001). The cancer detection rate was 3.2% for digital rectal examination, 4.6% for PSA and 5.8% for the 2 methods combined. Positive predictive value was 32% for PSA and 21% for digital rectal examination. Of 160 patients who underwent radical prostatectomy and pathological staging 114 (71%) had organ confined cancer: PSA detected 85 (75%) and digital rectal examination detected 64 (56%, p = 0.003). Use of the 2 methods in combination increased detection of organ confined disease by 78% (50 of 64 cases) over digital rectal examination alone. If the performance of a biopsy would have required suspicious transrectal ultrasonography findings, nearly 40% of the tumors would have been missed. We conclude that the use of PSA in conjunction with digital rectal examination enhances early prostate cancer detection. Prostatic biopsy should be considered if either the PSA level is greater than 4 μg./l. or digital rectal examination is suspicious for cancer, even in the absence of abnormal transrectal ultrasonography findings.
The Journal of urology. 2016 Dec 21 [Epub ahead of print]
William J Catalona, Jerome P Richie, Frederick R Ahmann, M'liss A Hudson, Peter T Scardino, Robert C Flanigan, Jean B DeKernion, Timothy L Ratliff, Louis R Kavoussi, Bruce L Dalkin, W Bedford Waters, Michael T MacFarlane, Paula C Southwick
Division of Urologic Surgery, Washington University School of Medicine, St. Louis, Missouri; Division of Urologic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts; Divisions of Urology and Hematology-Oncology, University of Arizona college of Medicine and Tucson Veterans Affairs Medical Center, Tucson, Arizona; Scott Department of Urology, Baylor College of Medicine, Houston, Texas; Department of Urology, Loyola University Medical Center, Chicago, Illinois; Division of Urology, UCLA School of Medicine, Los Angeles and Department of Clinical Research, Hybritech Incorporated, San Diego, California.