[Screening of cancer of the prostate: study in a Spanish population].

OBJECTIVES: A population of Spanish men aged over 49 years were screened for prostate cancer. The detection rate and the clinical features of the tumors found are analyzed.

METHODS: The study comprised two phases: Phase I: Subjects were evaluated by digital rectal examination (DRE) and prostate-specific antigen (PSA) was determined. Phase II: Subjects with a positive DRE or PSA > 4 ng/ml were evaluated by transrectal US. If PSA was > 10 ng/ml or DRE or transrectal US were abnormal, a transrectal biopsy was performed; most of these were sextant. PSA density was used as a criterion for biopsy in subjects with PSA 4-10 ng/ml and normal DRE and transrectal US. From June, 1993 to August 1994, 1091 subjects have been evaluated.

RESULTS: 1) The mean age was 59.32 years; 379 (34.7%) had low voiding symptoms. 2) 5.07% and 9.07% had abnormal DRE and PSA, respectively; 135 subjects (12.4%) with a questionable DRE and/or PSA were evaluated by transrectal US. 3) Of the 97 biopsies (8.8%) performed, prostate cancer was detected in only 11 (1%); 8.8 biopsies were required to detect one case of prostate cancer. 4) Clinically, 7 tumors (63.6%) were localized and 4 (36.3%) were in the advanced stages.

CONCLUSIONS: 1) The participation rate was low (21%). 2) The PSA mean increased with age. Prostate volume was the factor that most influenced PSA changes. 3) PSA detected more tumors (10 cases; 90.9%) than DRE (8 cases; 72.7%). Approximately 27.27% of the lesions were detected by PSA and not by DRE, while 9.09% were detected by DRE alone. 4) The detection rate was low (1.008%); 0.91% for PSA, 0.73% for DRE and 51% (n = 135) for transrectal US. 5) We have detected more tumors in the clinically advanced stages (36.6%) than other series, perhaps because this is the first time this type of study has been performed in this population. In view of the foregoing results, we do not advocate performing these studies routinely. Perhaps in subsequent studies with a longer follow up, a higher detection rate can be achieved for localized tumors that are potentially curable.