48 - Differing Colonic Adenoma Presentation in Adults With Cystic Fibrosis Compared to the General Population With Screening and Surveillance Colonoscopy

J. Alexander Torres, MD¹, Anand Singla, MD, MS¹, James Abraham, MD², Mark D. Derleth, MD^1
1University of Washington, Seattle, WA; ²University of Michigan, Brighton, MI

Introduction: People with CF (PwCF) experience increased rates of early colon polyp development and progression to colorectal cancer compared to the general population; a trend further magnified in patients with solid organ transplant. The exact mechanism for why CF patients develop more polyps and whether different polyp types occur at similar prevalence rates as the general population remains unclear. We developed a database of colonoscopy results in PwCF to better characterize the prevalence and location of varying polyp types.

Methods: In this retrospective chart review, PwCF were identified via the University of Washington (UW) CF Foundation Patient Registry and the UW CF Transplant Registry. Patients with a diagnosis of CF were included, however, those younger than 18 years old were excluded. Electronic medical records (EMR) were accessed using the UW’s Epic EMR system including linked archival data systems. Colonoscopy reports were systematically reviewed with selected variables including patient age at time of procedure, date of colonoscopy, bowel preparation quality, and cecal intubation. Polyp quantity, size, type, location, and presence of cancer were also collected. Statistical analysis was performed to assess our data compared to the general population. This study was approved by the UW IRB.

Results: Of 782 patients were identified, 181 had available colonoscopy records (any indication). A total of 306 colonoscopies were reviewed (53.6% women, 46.4% men). Median age at time of colonoscopy was 42 years old. Cecal intubation rate was 92.5%. A total of 295 polyps were identified; 43.7% of patients had at least 1 polyp and 27.1% had at least 2 or more polyps. Conventional adenomas represented 98.7% (n = 225) of all pre-cancerous polyps resected. Sessile serrated lesions and hyperplastic polyps were significantly less prevalent than what has been previously described in the general population (p< 0.05). Polyp location within the colon was predominantly left-sided (Table 1).

Discussion: PwCF had a significantly different polyp type distribution compared to what has been described in the general population. Conventional adenomas appear to be the near exclusive precancerous polyp type found in CF patients. SSLs appear to be rare in this population. This finding could have bearing on future study, particularly on impacts of highly-effective modulators on polyp formation and the efficacy of stool-based DNA testing for screening in this population.



Disclosures:


J. Alexander Torres, MD¹, Anand Singla, MD, MS¹, James Abraham, MD², Mark D. Derleth, MD¹, 48, Differing Colonic Adenoma Presentation in Adults With Cystic Fibrosis Compared to the General Population With Screening and Surveillance Colonoscopy, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.