From the Department of Medicine, University of Chicago, Chicago, Ill.
Edited by Ronna Henry Siegel, MD, Contributing Editor.
CANCER DETECTION continues to be an important focus of primary care.
Many groups, including the American Cancer Society and the US Preventive Services
Task Force, periodically publish recommendations for cancer screening. As
new information becomes available, these recommendations need reevaluation
and revision. In this article, we review recent studies that have modified
our approach to the detection of prostate cancer and colorectal cancer.
Screening for prostate cancer by serum prostate-specific antigen (PSA)
measurement continues to generate controversy. PSA testing is recommended
by the American Cancer Society1 but not by
the US Preventive Services Task Force.2 Critics
of PSA screening raise several concerns. First, there have been no randomized
trials showing that the detection of prostate cancer by PSA screening decreases
prostate cancer–associated morbidity or mortality. Second, autopsy studies
suggest that 30% of men have indolent tumors that develop late in life and
often do not affect survival.2 Third, PSA testing
has a high false-positive rate: in 1 study,3
78% of men with PSA levels of 4 to 10 ng/mL did not have prostate cancer on
prostate biopsy specimens. In addition, combined digital rectal examination
(DRE) and PSA screening may lead to prostate biopsies for 15% to 40% of tested
men.4 Finally, prostate cancer therapy is associated
with significant morbidity: radical prostatectomy has an estimated 30-day
mortality rate of 0.5%, a 30% risk of incontinence, and a 20% to 85% risk
of erectile dysfunction.4 Complications of
radiotherapy include gastrointestinal and genitourinary problems (8%-43%),
erectile dysfunction (40%-67%), incontinence (1%-2%), and death (0.2%-0.5%).2
Stern S, Altkorn D, Levinson W. Detection of Prostate and Colon Cancer. JAMA. 1998;280(2):117-118. doi:10.1001/jama.280.2.117