Prostate Cancer

Reviewing the Literature

RIU0368_12-12.qxd 12/12/07 8:29 PM Page 243 Prostate Cancer Prostate Cancer PSA Report Card Reviewed by Danil V. Makarov, MD, Alan W. Partin, MD, PhD The James Buchanan Brady Urological Institute, Department of Urology, The Johns Hopkins Medical Institutions, Baltimore, MD [Rev Urol. 2007;9(4):243-244] © 2007 MedReviews, LLC ince its discovery as a forensic agent in the 1960s1 and its subsequent identification in plasma,2 there have been many great advances in the use of prostate-specific antigen (PSA) in the diagnosis and screening of men with prostate cancer. Intuitively, there must be lag between discoveries being made in the laboratory, described in the medical literature, and applied in the care of the typical patient seen in the typical clinic. National medical organizations such as the American Cancer Society,3 the American Urological Association,4 the National Comprehensive Cancer Network,5 and the Veterans Affairs (VA) Health System6 bridge this gap by publishing guidelines, accessible to all, regarding the best practice use of PSA screening. It is interesting, however, to ask how well we as a profession are practicing what we preach and following those guidelines. How well are we educating our internal medicine colleagues regarding the best use of PSA? These several articles utilizing VA data published in the recent literature address this topic and seem to indicate that we have a ways to go before every patient receives “best practice” care. S out to characterize the extent of PSA screening in the VA health system among elderly men with limited life expectancies. The authors examined a cohort of 597,642 male veterans aged 70 years and older who received their medical care at 104 VA health centers during the years 2002 and 2003. These men had no prior history of prostate cancer, elevated PSA, or prostate cancer symptoms. Any serum PSA measurements, therefore, would presumably be for the purpose of prostate cancer screening. Data from the VA and Medicare 2003 claims were extracted to determine whether PSA had been measured. Health assessment was made using Charlson comorbidity scores, stratifying men into 3 groups: 0 representing best health at one extreme and 4 or greater representing worst health at the other. Despite the advanced age of this cohort, in whom screening is not recommended, 56% had serum PSA tests performed. As one might expect, PSA screening did decrease with advancing age. Surprisingly, it did not substantively decrease with declining health status. PSA rates ranged from 58% for men with the lowest Charlson scores, but decreased only to 51% in men with the highest. The large numbers of men in this study rendered this difference statistically significant, and these results are clearly higher than ideal. Indeed, among men aged 85 years and older, 34% in best health had a PSA test compared with 36% in worst health. In multivariable analyses, marital status and geographic region had a greater effect on the rate of PSA screening than did health. The authors conclude that PSA screening rates among these elderly men in poor health are too high and should be lower. Life expectancy should play a greater role in determining who should and should not be screened for prostate cancer using serum PSA. Walter LC, Bertenthal D, Lindquist K, Konety BR. Practitioner-Level Determinants of Inappropriate Prostate-Specific Antigen Screening JAMA. 2006;296:2336-2342. Kerfoot BP, Holmberg EF, Lawler EV, et al. PSA Screening Among Elderly Men With Limited Life Expectancies Arch Intern Med. 2007;167:1367-1372. An often frustrating situation for many urologists is the referral of an aged patient for “elevated PSA.” In many cases, these can be elderly and frail patients whom most urologists would never screen with serum PSA testing. Walter and colleagues begin by noting that guidelines do not recommend PSA screening in elderly men with limited life expectancies because the harms of screening (psychological and treatment related) outweigh whatever benefit someone with a short life expectancy may derive. They set The second study attempts to further characterize the root causes of inappropriate PSA screening. Also analyzing data from the VA health system, Kerfoot and associates examined a cohort of 181,139 male patients from 7 VA hospitals. Data on serum PSA screening from the years 1997 to 2004 were extracted. In an effort to determine whether specific physician characteristics or biases could explain inappropriate PSA testing, specific data on the VOL. 9 NO. 4 2007 REVIEWS IN UROLOGY 243 RIU0368_12-12.qxd 12/12/07 8:29 PM Page 244 Prostate Cancer continued 4823 health care providers ordering the PSA tests were also extracted. The analysis excluded patients who might have undergone PSA testing for non-screening reasons, such as those with a diagnosis of prostate cancer, taking prostate cancer-specific medications, or undergoing any prostate cancer-specific procedures. Inappropriate PSA testing was defined as PSA screening in patients older than 75 years or younger than 40 years. A mean of 19.3% of all PSA tests ordered were inappropriate, with 18.4% / 14.9% of providers ordering tests in patients older than 75 years and 0.8% / 3.0% in patients younger than 40 years. As one might expect, specific hospitals and infrequent PSA test orderers had significantly high levels of inappropriate testing. Less expected was the finding that urologists and male providers also had significantly higher levels of inappropriate PSA screening. Also unexpectedly, nurses and physician assistants had significantly lower levels of inappropriate PSA screening compared with attending physicians. Only infrequent PSA test ordering and hospital affiliation retained statistical significance in the final multivariable model. The percentage of inappropriate PSA screening increased significantly with the age of male health care providers ordering the PSA test. The authors conclude that several characteristics of health care providers are associated with PSA screening misuse. Like the previous study, this one demonstrates just 244 VOL. 9 NO. 4 2007 REVIEWS IN UROLOGY how frequently PSA screening is performed counter to evidence-based guidelines. There have been great advances made in PSA screening, yet these 2 studies clearly demonstrate that actual clinical practice significantly lags behind published guidelines for use of PSA screening. Although great controversy exists as to whether PSA screening for prostate cancer confers a survival advantage, in the absence of clear data demonstrating such an advantage, it is important for urologists and non-urologists alike to adhere to current screening guidelines and avoid PSA tests in populations where they may actually be harmful. References 1. 2. 3. 4. 5. 6. Makarov DV, Carter HB. The discovery of prostate specific antigen as a biomarker for the early detection of adenocarcinoma of the prostate. J Urol. 2006;176:2383-2385. Wang MC, Papsidero LD, Chu TM. Prostate-specific antigen, p30, gammaseminoprotein, and E1. Prostate. 1994;24:107-110. Smith RA, Cokkinides V, von Eschenbach AC, et al. American Cancer Society guidelines for the early detection of cancer. CA Cancer J Clin. 2002;52:8-22. Prostate-specific antigen (PSA) best practice policy. American Urological Association (AUA). Oncology. 2000;14:267-286. Prostate Cancer Early Detection. NCCN Clinical Practice Guidelines in Oncology. V.2; 2007 ed: National Comprehensive Cancer Network; 2006. Available at: http://www.nccn.org/professionals/physician_gls/ f_guidelines.asp?button=I+Agree#detection. Accessed October 15, 2007. National Veterans Administration Center for Health Promotion and Disease Prevention. Proposal for new clinical practice guideline for screening men for prostate cancer. 2004. Available at: http://www.oqp.med.va.gov/cpg/ Publications/USPSTF/Prostate%20Cancer.doc. Accessed October 2, 2007.