Yield of Index Colonoscopy Screening in Patients Under 50 Years of Age Who Have a Family History of Colon Cancer: A Validation of Current Screening Recommendations

Abstract

Purpose: To evaluate the yield of index screening colonoscopy in a cohort of asymptomatic patients between the ages of 18-49 with a non-syndromic family history of CRC. Methods: A retrospective analysis of Naval Medical Center Portsmouth's endoscopic database, from 2001 to 2009, identified patients with index colonoscopy performed due to family history. Patient information linked with index colonoscopy and pathologic results. Detected polyps were categorized according to their size, number, location and histology. Gender, age, BMI, tobacco and alcohol ingestion were assessed. Those with indications other than family history were excluded as were patients with personal or family history of syndromic large bowel cancers or polyposes. Results: The records 865 patient between the age 19 to 49 with a family history of CRC were reviewed. Eight hundred and forty-one patients (97.2%) were identified who met the inclusion criteria. Identified within this cohort were a total of 1109 polyps. Two hundred and seventy-four (24.7%) of the lesions were adenomatous, while 835 (75.29%) non-adenomatous (P<.001). Nine (.8%) advanced lesions were found. One hundred and twenty three (16.83%) and 145 (19.84%) non-adenomatous lesions localized to the sigmoid and rectum respectively (P<.001). Conclusion: Colonoscopic polypectomy resulted in a lower-than-expected incidence of adenomatous polyps 4,5. The low yield of adenomatous polyps in this study may in part be due to sample size and/or military members and their dependents screened. However this low yield does not lend strong support to the notion that colonoscopy is an appropriate-cost-effective first step in screening the asymptomatic patient with a family history of CRC or advanced adenomatous polyps.