Umair Iqbal, MD1, Nicholas J. Talabiska, DO2, Patrick May, MS3, David Talabiska, MD1, Bradley D. Confer, DO1 1Geisinger Medical Center, Danville, PA; 2Temple University Hospital, Philadelphia, PA; 3Geisiger Medical Center, Danville, PA
Introduction: Colonoscopy is the gold standard test for the screening for colorectal cancer. However, a colonoscopy may not be feasible in some patients either due to their reluctance for the procedure, lack of endoscopists in underserved areas and pandemic induced backlog of procedures. A non-invasive multi-target stool DNA test (Cologuard, Exact Sciences, Madison, WI) is an approved CRC screening tool for average-risk adults and is a reasonable alternative in average risk patients. A subset of patients with a positive Cologuard will have a negative colonoscopy and current guidelines recommend routine follow-up screening interval should be followed assuming high quality colonoscopy. However, quality of evidence is low, and these guidelines are based upon limited number of studies. Also, due to fear of missed cancer or large pre-cancerous polyp, many endoscopists do not feel comfortable with long screening intervals and may pursue unnecessary workups or shorten the colonoscopy interval.
Methods: A multicenter historic cohort was conducted at Geisinger Health System from May 2016 to August 2022 including patients over 45 years of age who underwent colonoscopy for a positive Cologuard. Patients with a family history of colon cancer or inflammatory bowel disease were excluded from the study. True positive Cologuard was defined as the finding of colorectal cancer or ≥10 mm colonic polyp.
Results: During the study period, 3444 patients had a colonoscopy for positive Cologuard. Out of these 297 (8.6%) patients with inflammatory bowel disease and 89 (2.6%) patients with a family history of colon cancer were excluded from the final analysis. Therefore, 3065 patients were included in the final analysis. The median age of included patients was 63.0 (56.0, 69.0), there were 1427 males, and the median BMI was 30.3 (26.2, 35.2). The rate of true positive Cologuard was 28% and there was a total of 6 cancers missed on colonoscopy. The rate of missed cancer was 0.2% with a median follow-up of 3.3 years (1.7, 4.3). The median time from missed colon cancer diagnosis on initial colonoscopy to eventual diagnosis was 2.4 years (1.9, 3.1).
Discussion: Our study revealed a very low rate of missed colon cancer in patients with positive Cologuard and negative colonoscopy. This is similar or lower to what has been reported for average risk patients undergoing a routine screening colonoscopy. We suggest following regular screening intervals for these patients and avoiding short interval repeat colonoscopies for re-evaluation.
Disclosures:
Umair Iqbal indicated no relevant financial relationships.
Nicholas Talabiska indicated no relevant financial relationships.
Patrick May indicated no relevant financial relationships.
David Talabiska indicated no relevant financial relationships.
Bradley Confer: Boston Scientific Corporation – Consultant.
Umair Iqbal, MD1, Nicholas J. Talabiska, DO2, Patrick May, MS3, David Talabiska, MD1, Bradley D. Confer, DO1. P3188 - Rate of Missed Colorectal Cancer in Patients With Positive Cologuard and Negative Colonoscopy, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.