PSA Screening for Prostate Cancer at Western Medical Clinic Kardy Fedorowich University of Manitoba Max Rady College of Medicine

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1 PSA Screening for Prostate Cancer at Western Medical Clinic Kardy Fedorowich University of Manitoba Max Rady College of Medicine Abstract While PSA screening for prostate cancer remains a widely used tool by physicians across Canada, there are conflicting guidelines regarding its use. The Canadian Urology Association recommends the use of PSA screening annually in men between the ages of 50 and 75, whereas the Canadian Task Force for Preventative Health Care recommends against PSA screening from a population health perspective. With the disagreement of guidelines, the decision to screen for prostate cancer falls upon the family physician. At Western Medical Clinic in Brandon, MB a chart audit revealed a screening rate of 73% for prostate cancer. While this indicates a clear tendency to utilize PSA screening, the development of congruent guidelines in Canada is necessary to optimize health outcomes and financial considerations at the population health level. Introduction Prostate cancer represents a significant burden in Canada, both in terms of economics and health status. The Canadian Cancer Society estimated 24,000 men to be diagnosed with prostate cancer in 2015, equivalent to an incidence rate of 99 per 100, Furthermore, the lifetime probability of a Canadian man developing prostate cancer is 1 in 8, while 1 in 27 will die from it. To put this in perspective, prostate cancer accounts for 10% of all cancer deaths in men and is the third leading cause of death from cancer in Canada as such. From a financial outlook, studies have reported that the average cost of prostate management over a five-year period is more than $42, As with most cancers, there are a number of risk factors which may increase a patient s probability of developing prostate cancer. Perhaps the most significant risk factor is age, with the incidence rate rising steadily after the age of Other risk factors include family history and genetics, race, diet, smoking and a history of chemical exposures. Definitive diagnosis of prostate cancer requires tissue biopsy and is typically followed by assessment via the Gleason Score, indicating the aggressiveness of the tumor. Prognosis clearly depends on the cancer staging, however in Canada, the 5-year relative survival is 96% 1, reflecting the responsiveness of prostate cancer to treatment. A multitude of treatment options exist and are dependent on the specifics of the malignancy itself, as well as the patient and their situation. Treatment modalities include active surveillance without intervention, a radical prostatectomy, radiation therapy, hormonal therapy, chemotherapy or a combination of the latter three. To further improve survival outcomes of those diagnosed with prostate cancer, the emphasis turns to detecting the cancer in its early stages when patients do have it. The two primary methods of screening for prostate cancer include the digital rectal exam and PSA blood test. The digital rectal exam alone can be useful in detecting abnormalities

2 of the prostate, however it is not specific nor sensitive enough to be used as the sole method for prostate cancer screening. 4 For this reason, the PSA value is the most commonly used method for prostate cancer screening, despite conflicting guidelines regarding its use. Prostate specific antigen (PSA) is a glycoprotein produced by epithelium of the prostate and can be detected in the circulating bloodstream. The normal range of the PSA varies with age and the individual, however a general guideline that has been suggested is shown in Figure 1. 5 PSA screening for prostate cancer relies on the principle that the PSA value will be elevated in the case of an individual with prostate cancer. While this is true, it is important to realize that this principle is not exclusive as there are a variety of causes of an elevated PSA. The most common benign causes for an elevated PSA value include benign prostatic hyperplasia and prostatitis, however other inconsistent causes include an immediately recent digital rectal examination or ejaculation. 5 Figure 1. Normal PSA ranges based on age. 5 To distinguish between benign and malignant causes of an elevated PSA, it is important to follow the trend of the PSA value over time and utilize objective measures such as PSA velocity, which measures the rate of PSA increase over time. Those with a change in their PSA levels of 0.75 ng/ml/yr have been found to be at at an increased risk for being diagnosed with prostate cancer. 6 Additionally, it has been suggested that circulating levels of free PSA, as opposed to that which is protein bound, are relatively lower in the case of prostate cancer as compared to benign causes of elevated PSA. 7 There is conflicting evidence regarding the use of PSA levels alone as a predictor of prostate cancer in men. One randomized trial of nearly 77,000 men found there to be no significant benefit of routine PSA screening as compared to opportunistic PSA screening at a thirteen year follow up. 8 In contrast, a different randomized study of more than 162,000 men indicated a 21% relative risk reduction of PSA screening for prostate cancer at thirteen year follow up. 9 While the potential benefits for a screening program are more obvious, it is also necessary to consider the potential harms incurred to patients as a result. Perhaps the most concerning harm is the risk of a false-positive, which has been found to range from 3% to 12%. 10 A false positive may lead a patient to undergo an invasive prostate biopsy, carrying its own significant risks including infection and hospital admission. One most also consider the psychosocial stress placed on a patient who believes they may have cancer and is undergoing an invasive procedure. Another potential harm involves a patient undergoing treatment for prostate cancer, when they may have been otherwise asymptomatic and died from unrelated causes. While the incidence of this occurring cannot be measured, it has been suggested as another consideration to be made when evaluating a prostate cancer screening program. 11 The disagreement in evidence surrounding PSA screening has led to the presence of opposing guidelines in Canada at this time. The Canadian Task Force for Preventative Health Care (CTFPHC) released a guideline in 2014 in conjunction with the College of Family Physicians of Canada which recommended against PSA screening for prostate cancer, regardless of patient age 11.In opposition is a guideline developed by the Canadian Urological Association in 2011, recommending PSA screening in men between the ages of 50 and 75 with an average risk of developing prostate cancer. 12 Furthermore, the Canadian Urological Association suggests the

3 option of acquiring baseline PSA levels in average risk men from age 40 to 49 for use later in life, as well as screening high risk patients at age Patients classified as high risk have a higher than average baseline PSA level, as well as the presence of one or multiple risk factors mentioned above. With the differences in guidelines, the decision to routinely screen for prostate cancer using the PSA test falls upon the family physician. This study looks at the rates of PSA screening within Western Medical Clinic to obtain a better understanding as to which guideline physicians within the clinic tend to follow. Methods The electronic medical records at Western Medical Clinic are managed through Accuro, a suite of medical software. Within Accuro, a chart audit was performed to evaluate the rate of PSA screening within Western Medical Clinic. The inclusion criteria were male patients over the age of 50 who have had an appointment for a full physical with their family physician since June 1, The exclusion criteria were the following: female, younger than age 50, appointment for full physical prior to June 1, 2015, history of prostatectomy, or current diagnosis of prostate cancer. These criteria are provided in Figure 2. From these criteria, the chart audit revealed 1065 patient charts, of which 100 were randomly selected and identifying data was removed. There were six charts which met one or more of the exclusion criteria, resulting in a total of 94 charts for the audit. Figure 2. The inclusion and exclusion criteria defined and used for the chart audit. Each chart was evaluated on an individual basis to determine whether a PSA test had been ordered at the patient s physical. PSA screening was considered to have been done if a lab requisition for a PSA value was ordered either at the appointment of the physical, or within the previous six months prior to the patient s physical. If a PSA test was not ordered, the patient encounter note written by the physician was examined to determine if the patient voluntarily chose not to undergo PSA screening. In conjunction with the chart audit, an anonymous survey regarding PSA screening was distributed via Google Forms to all family physicians at Western Medical Clinic. This survey inquired as to which guideline regarding PSA screening physicians tended to agree with/follow, whether physicians informed patients of risks/benefits of PSA screening, and the subsequent course of action if a patient s lab work revealed an elevated PSA value. A full copy of the survey can be found in the attached appendix. The results of this survey were analyzed and are discussed below. Results Of the 94 charts randomly selected which fit the inclusion criteria and subsequently evaluated for PSA screening, there were 69 cases of routine PSA screening, translating to a rate

4 of 73.4% (illustrated in Figure 3). In the cases of the 25 charts where PSA screening was performed, there was no documented incidences of discussion with the patient regarding PSA screening, nor was there any cases in which the patient voluntarily declined to undergo screening. There were three incidences of an elevated PSA value. One of the cases was referred for urology consultation given a history of consecutive elevated PSA values. Another was dismissed given the patients high age and known history of benign prostatic hypertrophy. A repeat PSA test was ordered in six months time in the third case of elevated PSA. Despite the survey regarding PSA Figure 3. Results of the chart audit indicating a 73.4% PSA screening rate for prostate cancer at Western Medical Clinic. screening being distributed to thirteen physicians within Western Medical Clinic, only five responses were obtained. Four out of the five physicians who completed the survey indicated they agreed with the guideline set forth by the Canadian Urology Association. All physicians indicated they routinely discuss the PSA test with their patients, including information regarding risks and benefits, before moving forth with screening. Of the four physicians who indicated they routinely utilize PSA screening, a general consensus was set forth that they generally require three consecutive, elevated PSA values over the course of months before referring the patient for further investigation. Discussion Without consistent guidelines in Canada, family physicians are left at their own clinical judgement and discretion whether or not to routinely conduct PSA screening for prostate cancer. Given the discrepancies in guidelines at this time, this study aimed to evaluate the rates of PSA screening at Western Medical Clinic and to obtain an appreciation as to physicians thoughts regarding the use of screening for prostate cancer. A screening rate of 73% clearly indicates a tendency for most physicians to routinely utilize the PSA test as a component of a patient s annual physical. In comparison, the screening rate illustrates agreeance with the results of the survey conducted, where 80% of responses favored to follow the Canadian Urology Association s recommendation to screen men between the age of 50 and Despite the congruence between the results of the chart audit and the survey, it is necessary to realize the sub-optimal study size and lack of survey responses. If time permitted, a thorough audit of all 1065 charts which met the inclusion criteria would provide more significant information for the results of the study. Furthermore, survey responses from all physicians in the clinic and even throughout the province would provide a better appreciation of family physicians clinical opinion regarding PSA screening guidelines.

5 It is also plausible to consider the current motivation behind the use of PSA screening, as it is entirely possible that without clear guidelines, PSA screening is conducted for liability protection from a physician s perspective. Although impossible to accurately assess, it would be noteworthy to determine what percentage of PSA screening this accounts for. Depending on whether or not this is a true occurrence, there may be substantial financial benefit from developing consistent guidelines that release physicians from the pressure of screening for personal liability issues. Moving forward, it is clear that physician opinion remains the principle factor for decisions of PSA screening at Western Medical Clinic; a statement that can be arguably generalized to describe Canada as a whole. While there have been a number of significant studies which have attempted to objectively evaluate the use of PSA screening for prostate cancer, 8,13,14 the evidence continues to remain conflictive. Perhaps we need to evaluate the use of PSA velocity instead of PSA values alone as the method behind prostate cancer screening, given the thought that PSA velocity may be more specific and sensitive to prostate cancer. 6 Further evidence is required regarding both health outcomes and financial considerations to develop convincing conclusions for a prostate cancer screening program. Until such time, patient involvement remains a necessary component in a physician s decision regarding PSA screening for prostate cancer. References 1. Canadian Cancer Society s Advisory Committee on Cancer Statistics. Canadian Cancer Statistics Wilson LS, Tesoro R, Elkin EP, et al. Cumulative cost pattern comparison of prostate cancer treatments. Cancer. 2007;109(3): doi: /cncr Fradet Y, Klotz L, Trachtenberg J, Zlotta A. The burden of prostate cancer in Canada. J Can Urol Assoc. 2009;3(3 SUPPL. 2): Schroder FH, Kruger AB, Rietbergen J, et al. Evaluation of the Digital Rectal Examination as a Screening Test for Prostate Cancer. JNCI J Natl Cancer Inst. 1998;90(23): doi: /jnci/ Wheeler SG, Wipf JE, Staiger TO, Deyo RA, Park L. Measurement of Prostate Specific Antigen. UptoDate. 2016;(table 2). doi: /j x x. 6. Hutchinson D, Ho V, Dodd M, Dawson HN, Zumwalt AC, Colton CA. Longitudinal Evaluation of Prostate-Specific Antigen Levels in Men With and Without Prostate Disease. 2008;148(4): doi: /jid Catalona WJ, Partin AW, Slawin KM, al. et. Use of the precentagve of free prostatespecific anigen to enhance differentiation of prostate cancer from benign prostatic disease: a prospective multicenter clinical trial. Jama. 1998;279(19): Andriole GL, Crawford ED, Grubb RL, et al. Prostate cancer screening in the randomized prostate, lung, colorectal, and ovarian cancer screening trial: Mortality results after 13 years of follow-up. J Natl Cancer Inst. 2012;104(2): doi: /jnci/djr Nelen V, Kwiatkowski M, Lujan M, Määttänen L. Cancer Prostate Cancer Mortality at 13 Years of Follow-up. 2015;384(9959): doi: /s (14)60525-

6 0.The. 10. Kilpeläinen TP, Tammela TLJ, Määttänen L, et al. False-positive screening results in the Finnish prostate cancer screening trial. Br J Cancer. 2010;102(3): doi: /sj.bjc Krahn M. Prostate cancer screening: Going beyond the clinical evidence. Cmaj. 2014;186(16): doi: /cmaj Izawa JI, Klotz L, Robert Siemens D, et al. Prostate cancer screening: Canadian guidelines J Can Urol Assoc. 2011;5(4): doi: /cuaj Andriole G, Crawford E. Mortality results from a randomized prostate-cancer screening trial. Engl J. 2009;360(13): doi: /nejmoa mortality. 14. Hugosson J, Carlsson S, Aus G et al. Mortality results from the Göteborg Randomised Prostate Cancer Screening Trial. Lancet Oncol. 2011;4(164): doi: /scisignal engineering.

7 APPENDIX A PSA Screening Rates at WMC Kardy Fedorowich M1 Home for the Summer Program As part of the Home for the Summer program, I am required to complete a short project with clinical relevance for submission to the program director. In this regard, I chose to look at the use of PSA screening within the clinic to determine how often it is routinely done and the opinion of physicians as to its clinical significance. If you have time, I would very much appreciate you filling out this quick survey. For each question, please circle/indicate which answer you agree with. Thank you! 1. There are conflicting guidelines in Canada as to whether PSA screening should be routinely ordered or not. Which of the following do you tend to use/agree with? Canadian Urology Association: Annual PSA screening for prostate cancer for men over age 50 Canadian Task Force for Preventative Health Care: No screening recommended for prostate cancer using the PSA test (endorsed by College of Family Physicians of Canada). 2. Do you discuss the risks/benefits of the PSA test with your patients or do you tend to decide whether or not to order the test based on your own clinical judgement? I discuss the risks/benefits of the PSA test with my patients before deciding whether or not to order it. I decide to order/not order the PSA test based on clinical judgement without consulting the patient. Please answer the following questions IF you repeat the PSA test for multiple values before referral. How many consecutive elevated PSA values do you usually wait before referral for further evaluation/biopsy? In what time frame do you order the repeat PSA test(s) (Ex. monthly, every 6 months, etc.)?