Journal of the American Academy of Physician Assistants:
Nesi, Juliana; Niemeyer, Melanie; White, Kristen; Bushardt, Reamer L. PharmD, PA-C
Juliana Nesi, Melanie Niemeyer, and Kristen White are students in the PA program at Wake Forest School of Medicine in Winston-Salem, N.C. Reamer L. Bushardt is professor and chair of the Department of Physician Assistant Studies at Wake Forest School of Medicine and editor-in-chief of JAAPA. The authors have indicated no relationships to disclose relating to the content of this article.
Jennifer M. Coombs, PhD, PA-C, and Alison C. Essary, MHPE, PA-C, department editors
WHO SHOULD READ THIS?
PAs who provide care to older adults and those who refer patients for cancer screenings.
WHY IS COLORECTAL CANCER SCREENING IMPORTANT?
According to the US Preventive Services Task Force (USPSTF), colorectal cancer is the second leading cause of cancer deaths in the United States and the third most common type of cancer.1 Colorectal cancer typically originates from small benign polyps within the colonic mucosa. A majority of these polyps are histologically identified as adenomatous.2 A small percentage of adenomatous polyps progress to cancer; however, the risk of developing colon cancer significantly increases with increasing number of adenomatous polyps.2 Therefore, colorectal cancer screening is an essential component in preventive medicine and may save up to 18,800 lives per year.1
WHICH SCREENING TESTS ARE USED TO DIAGNOSE COLORECTAL CANCER?
The three most common screening tools used in the detection of colorectal cancer are guaiac-based fecal occult blood tests, flexible sigmoidoscopy, and optical colonoscopy. Other screening tools include the immunochemical-based fecal occult blood test, stool DNA panel, double-contrast barium enema, and CT colonography. Colonoscopy allows visualization of the entire colon and is widely regarded as the gold standard for detecting colorectal cancer.3 Other screening tests generally serve as adjuncts to colonoscopy or are used in patients who are not candidates for colonoscopy because of age or comorbidities.
WHO BENEFITS FROM COLONOSCOPY SCREENINGS?
Only about half of all routine screening colonoscopies are normal and require no polypectomy.4 The USPSTF recommends that screenings begin at age 50 years for normal-risk patients and continue every 10 years until age 75 years. For patients older than 85 years, the USPSTF states that the risks outweigh the benefits and routine screening should be discontinued.1 The USPSTF recommends against routine colorectal cancer screening in patients ages 76 to 85 years.1 However, individual circumstances may warrant a routine colorectal cancer screening in a patient aged 76 to 85 years.1 Each provider must decide whether to continue screening based on the benefits and risks for each patient.
WHAT ARE THE RISKS OF COLONOSCOPY SCREENING?
Clinicians must carefully assess comorbidities and procedural risks before recommending that a patient undergo colonoscopy. Serious complications such as perforation, diverticulitis, and adverse cardiovascular events occur in about 25 of 10,000 procedures (Table 1).1 Although these complications are uncommon, adverse events are more likely to occur in older adults and should be taken into account.5 The value of the screening procedure must be carefully evaluated in the context of the patient's age and health status. Common comorbidities in older adults include diabetes, stroke, chronic obstructive pulmonary disease, atrial fibrillation, and heart failure. Patients with these comorbidities have an increased risk of serious adverse events following a colonoscopy.5 These comorbidities increase the risk of complications and contribute to decreased life expectancy that ultimately reduces the benefit of colorectal cancer screening.
WHAT OTHER SIGNIFICANT PROBLEMS SHOULD PAs BE AWARE OF?
Inappropriately shortened intervals between screening colonoscopies continue to be a source of concern during a time of rising healthcare costs. The USPSTF recommends screening colonoscopy every 10 years. However, about 46% of Medicare patients with a negative screening underwent a repeat examination in about 7 years. In more than 42% of cases, no clear indication existed for the early repeated examination.6 In the United States, the average colonoscopy costs $1,185 and overuse contributes to the healthcare burden.7 Since Medicare coverage for colonoscopies was approved in 2001, concern regarding the overuse of screening colonoscopies has intensified.5 Shortened screening intervals not only deplete limited resources but also expose patients to unnecessary procedural risks.8 Following guidelines is an important step in reducing healthcare costs.
Often, discrepancies exist between current guidelines and endoscopists' recommendations for repeat screening colonoscopy intervals. In nearly 40% of cases, endoscopists advise routine colonoscopy screening at shorter intervals than recommended by the current guidelines.4 This puts primary care providers in a difficult situation. Communication between endoscopists and primary care providers is often poor, which may explain why many patients undergo repeat screening earlier than recommended by current guidelines. Medicolegal consequences could arise if primary care providers deviate from endoscopist recommendations.4 Open, timely communication between primary care providers and endoscopists is a best practice for determining when a patient should undergo repeat colonoscopy screening.
IS THERE ANYTHING NEW?
Recommendations stressing the importance of approaching each patient as an individual have been gaining favor recently. The American College of Physicians' guidance statement in 2012 emphasizes that providers should take into account comorbidities such as diabetes, cardiopulmonary disease, and stroke when determining whether a patient is a candidate for colorectal screening.9 Comorbid conditions influence life expectancy, and life expectancy is a major factor shaping the decision to perform routine colorectal screening.
Risk calculators that incorporate patient comorbidities and functional status to generate an estimate of life expectancy are available online. Such tools may aid clinicians in the decision to continue or cease screening. One example is ePrognosis, a website developed by the University of California at San Francisco.10 The website offers online calculators for possible mortality outcomes in older adults. By using resources that help calculate life expectancy, providers are given additional insight into the decision to continue performing routine colorectal cancer screening for patients older than 75 years.
1. Calonge N, Petitti DB, DeWitt TG, et al. Screening for colorectal cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med
2. Cappell MS. The pathophysiology, clinical presentation, and diagnosis of colon cancer and adenomatous polyps. Med Clin N Am
3. Zauber AG, Lansdorp-Vogelaar I, Knudsen AB, et al. Evaluating test strategies for colorectal cancer screening: a decision analysis for the U.S. Preventive Services Task Force. Ann Intern Med
4. Krist AH, Jones RM, Woolf SH, et al. Timing of repeat colonoscopy: disparity between guidelines and endoscopists' recommendation. Am J Prev Med
5. Warren JL, Klabunde CN, Mariotto AB, et al. Adverse events after outpatient colonoscopy in the Medicare population. Ann Intern Med
6. Goodwin JS, Singh A, Reddy N, et al. Overuse of screening colonoscopy in the Medicare population. Arch Intern Med
8. Lin OS, Kozarek RA, Schembre DB, et al. Screening colonoscopy in very elderly patients: prevalence of neoplasia and estimated impact on life expectancy. JAMA
9. Qaseem A, Denberg TD, Hopkins RH Jr, et al.. Screening for colorectal cancer: a guidance statement from the American College of Physicians. Ann Intern Med
© 2014 American Academy of Physician Assistants.