Appropriateness and Completion of Multitarget Stool DNA Testing in Primary and Subspecialty Care

ABSTRACT

Introduction: Colorectal cancer (CRC) is the third most prevalent cancer in the United States, with a 4% lifetime incidence. While more clinicians have begun ordering multitarget stool DNA (mt-sDNA) testing due to the COVID-19 pandemic, adherence to guidelines on mt-sDNA and rates of subsequent follow-up testing has not been well studied. We assessed the appropriateness of mt-sDNA orders and rate of high-quality colonoscopy completion following a positive result in a large academic medical center. Method(s) We identified patients ordered for mt-sDNA in primary care and gastroenterology clinics at our institution between April 2020 and July 2021. For each case, we reviewed the appropriateness of mtsDNA testing, documentation of shared decision making, result of testing, and subsequent follow-up. Appropriateness was defined in accordance to the most recent American College of Gastroenterology guidelines on mt-sDNA use for CRC screening. Result(s) Of the 797 patients in our study, 685 (86%) met all appropriateness criteria for mt-sDNA testing (Table). Shared decision making was documented in 488 (62%) cases, and the most common reason for ordering mt-SDNA was hesitancy for colonoscopy. 483 patients (61%) completed mt-sDNA testing, of which 74 cases (15%) were positive. Rates of positivity were higher in cases of inappropriate (28%) rather than appropriate (13.7%) orders (p = 0.01). Colonoscopy was ordered in 73 cases (99%) and completed by 59 patients (80%). Of the 56 patients who underwent colonoscopy at our institution, most had documentation of a high-quality colonoscopy, defined as adequate prep (84%), cecal intubation (93%), visualization of the appendiceal orifice and ileocecal valve (94%), and right colon retroflexion (83%). Sixteen patients (29%) were found with advanced adenomas and 19 (34%) had other adenomas or sessile polyps. Among the 409 patients with negative tests, a 3-year follow-up recommendation was documented for 369 patients (90%). Conclusion(s) Most clinicians at our institution identified appropriate patients for mt-sDNA testing and provided appropriate follow-up< and the majority of patients who underwent colonoscopy had documentation of a high-quality colonoscopy. In contrast, there were suboptimal rates of mt-sDNA completion and documentation of shared decision making. Further studies are needed to identify barriers to documentation of shared-decision making and to completion of high-quality colonoscopies in patients being screened with mt-sDNA.