Prostate-specific Antigen Screening For Prostate Cancer Research Articles

Selections from current literature: PSA screening for prostate cancer.

Prostate cancer has been the focus of several recent reports in the US news media.Additional attention has been focused on this issue due to the disclosure by several prominent US individuals that they have or have had prostate cancer. These include US presidential candidate, Senator Robert Dole, Gulf War hero, retired General Norman Schwarzkopf and the billionaire financier Michael Milken. Such specific cases highlight the fact that prostate cancer—'the man's cancer'—has risen sharply both in incidence and prevalence over the last few years. In men, prostate cancer is the most common type of cancer in the US and the second leading cause of cancer mortality. In 1996, it is estimated that there will be 317 100 new cases and 41 400 deaths as a result of prostate cancer in the US. The lifetime probability of a man developing prostate cancer is one in five. Currently the adjusted death rate from this disease among men living in industrialized countries of the world is greater than 15 per 100 000 population. What has caused this epidemic? A partial answer is the use of prostate specific antigen (PSA) as a screening test which has led to the diagnosis of many cancers that would have otherwise have remained undiagnosed, and never become clinically significant. This then leads to the question now being debated in the literature, fuelled by contradictory guidelines from several highly respected agencies: to screen or not to screen with PSA? The American Cancer Society (ACS) and the American Urological Association (AUA) currently recommend annual PSA testing for all men aged 50 years and older. The American Academy of Family Physicians (AAFP), Canadian Task Force on the Periodic Health Examination (CTF) and National Cancer Institute (NCI) all recommend against routine PSA screening in asymptomatic men. Furthermore, the recently published guidelines by the United States Preventive Services Task Force (USPSTF) also recommend against routine PSA screening.

Prostate-specific antigen in mass screening for carcinoma of the prostate.

Prostate-specific antigen (PSA) has various advantages over prostatic acid phosphatase (PAP) as a marker for prostate cancer, but its role in prostate cancer mass screening remains controversial. We measured serum PSA in addition to serum PAP determination and digital rectal examination (DRE) in our mass screening program to assess the usefulness of PSA for prostate cancer mass screening. Serum PSA and PAP measurements and DRE were performed in 1249 patients in mass screening for carcinoma of the prostate in 1989 and 1990. Thirteen cancers were diagnosed. We calculated the mean plus standard deviations (2SD) of the PSA and PAP values of men without cancer, and assessed the usefulness of PSA for prostate cancer screening by using these figures as the upper limit of normal. The number positive for PSA, PAP and DRE were 39, 36 and 48, respectively. If our screening had been performed without DRE, three cancers would have remained undetected, and the number would have been the same if performed without PSA. If the screening had been performed without PAP, on the other hand, no cancers would have remained undetected. The sensitivities of PSA and PAP were 54% and 23%, respectively. The screening detection rate with DRE and PSA was 0.88%, and with DRE and PAP was 0.64%. Measurement of serum PSA values with adjustment of the cut-off value was considered more useful than PAP in mass screening for prostate cancer.