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Prostate specific antigen--a screening test for prostatic cancer?

C S Powell·A M Fielding·K Rosser·A C Ames·K C Vaughton
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Abstract

A series of 287 patients referred by their family doctors with symptoms of bladder outflow obstruction were asked to attend the hospital for "pre-clinic" screening for carcinoma of prostate (CaP). Blood samples were collected from 211 patients and analysed for serum prostate specific antigen (PSA) and prostatic acid phosphatase (PAP). Thirty-six patients had a serum PSA greater than 10 micrograms/l and 7 had PAP levels greater than 5 iu/l. In no instance was the PAP elevated without an associated increase in PSA concentration. Patients with raised markers underwent further investigations which included prostatic biopsy and/or resection; 17 patients were proved to have carcinoma of the prostate, 9 of whom had distant metastases. The specificity of PSA for detecting prostate cancer in this study was 90% with a sensitivity of 89.5%, in contrast to values for PAP of 100% and 36.8%. The routine use of PAP as a marker for prostatic cancer should be abandoned. The use of PSA as a screening test in a group of patients with prostatism appears justified, but with a positive predictive value of only 47%, its use in a mass unselected screening programme is not recommended.

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Acid PhosphataseAgedAged, 80 and overAntigens, NeoplasmBiomarkers, TumorHumansMaleMiddle AgedPredictive Value of TestsProstateProstate-Specific AntigenProstatic NeoplasmsJournal ArticleResearch Support, Non-U.S. Gov't

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C S Powell, A M Fielding, K Rosser, A C Ames, K C Vaughton. 1989. Prostate specific antigen--a screening test for prostatic cancer?. https://doi.org/10.1111/j.1464-410x.1989.tb05287.x

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