It is a long-held belief in the United States that early detection and treatment of prostate cancer can lead to lower rates of metastasis and death. However, findings from some well-designed studies do not support this belief. The American Urologic Association and the American Cancer Society recommend routine screening for prostate specific antigen (PSA) in men older than 50 years of age, whereas the U.S. Preventive Services Task Force recommends against this screening. Fowler and colleagues conducted two national surveys of physicians to determine if primary care physicians and urologists had similar beliefs about early detection of prostate cancer and the effectiveness of different therapies for patients with prostate cancer at various stages.
Two survey instruments were developed, one for primary care physicians and the other for urologists. Both surveys asked about diagnosis of and treatment practices for benign prostatic hyperplasia and prostate cancer. Specifically, primary care physicians were asked how often they performed digital rectal examinations (DRE) and PSA tests and how often they recommended biopsy in patients with PSA levels of 4 to 10 ng per mL (4 to 10 mg per L). Urologists were asked if they thought primary care physicians should routinely perform DRE and PSA tests, and if they would recommend biopsy in patients with PSA levels of 4 to 10 ng per mL (4 to 10 mg per L). All of the physicians surveyed were asked if they thought radical prostatectomy and radiation therapy offered a survival benefit in patients with more or less than 10 years of life expectancy, or if watchful waiting was the more appropriate approach.
Of the 870 primary care physicians eligible for the study, 444 responded (response rate: 51 percent). Of the 582 urologists surveyed, 394 (68 percent) responded. The authors stress that primary care physicians' responses were compared with urologists' responses not because the latter's answers were necessarily “right,” but because urologists are the subspecialists most likely to treat patients with prostate cancer. Almost all (90 percent) of the primary care physicians included DRE as part of routine examinations in men between 50 and 80 years of age. Urologists concurred that DRE should be part of the routine care for men in this age group. In addition, urologists were almost unanimous in recommending that primary care physicians perform DREs routinely in men between 50 and 75 years of age and that PSA testing be performed in men between 50 and 70 years of age. Eighty-eight percent of urologists also recommended routine PSA testing in men between 70 and 74 years of age. PSA testing was rarely recommended in men older than 80 years of age.
The pattern of PSA testing reported by primary care physicians did not change with patient age as sharply as the recommendations reported by the urologists. Most primary care physicians reported that they still routinely order PSA tests in men older than 80 years.
Most urologists (80 percent) recommend prostate biopsy in patients younger than 60 years of age if their PSA levels are between 4 and 10 ng per mL (4 to 10 mg per L). Only one third of urologists would recommend biopsy in patients 70 to 74 years of age. In contrast, primary care physicians said they routinely referred patients in this age group for biopsy. All physicians agreed that radical prostatectomy offered little benefit to patients with a life expectancy of less than 10 years. Most physicians believed that “watchful waiting” was appropriate in these patients.
In an accompanying editorial, Wilt offers several reminders: routine DRE has not been shown to reduce prostate cancer mortality; PSA testing is unlikely to benefit patients with a life expectancy of less than 10 years and surgical treatment for prostate cancer is associated with a high risk of cardiopulmonary complications in the month after surgery in men older than 65 years. He recommends that men requesting PSA testing should be educated about the risks and potential benefits of such screening, and that PSA testing should not be done if a patient's life expectancy is less than 10 years. He further states that the best treatment for clinically localized prostate cancer is currently not known.
editor's note: The American Academy of Family Physicians currently does not recommend routine prostate cancer screening. The editorial clearly underscores the need to use available evidence, not just plausible assumptions, as the basis for medical practice. This step may require extensive education of patients and will certainly require more randomized trials.—g.b.h.