Published online Feb 28, 2018. doi: 10.3748/wjg.v24.i8.905
Peer-review started: August 5, 2017
First decision: August 30, 2017
Revised: November 17, 2017
Accepted: December 5, 2017
Article in press: December 5, 2017
Published online: February 28, 2018
To determine the frequency and risk factors for colorectal cancer (CRC) development among individuals with resected advanced adenoma (AA)/traditional serrated adenoma (TSA)/advanced sessile serrated adenoma (ASSA).
Data was collected from medical records of 14663 subjects found to have AA, TSA, or ASSA at screening or surveillance colonoscopy. Patients with inflammatory bowel disease or known genetic predisposition for CRC were excluded from the study. Factors associated with CRC developing after endoscopic management of high risk polyps were calculated in 4610 such patients who had at least one surveillance colonoscopy within 10 years following the original polypectomy of the incident advanced polyp.
84/4610 (1.8%) patients developed CRC at the polypectomy site within a median of 4.2 years (mean 4.89 years), and 1.2% (54/4610) developed CRC in a region distinct from the AA/TSA/ASSA resection site within a median of 5.1 years (mean 6.67 years). Approximately, 30% (25/84) of patients who developed CRC at the AA/TSA/ASSA site and 27.8% (15/54) of patients who developed CRC at another site had colonoscopy at recommended surveillance intervals. Increasing age; polyp size; male sex; right-sided location; high degree of dysplasia; higher number of polyps resected; and piecemeal removal were associated with an increased risk for CRC development at the same site as the index polyp. Increasing age; right-sided location; higher number of polyps resected and sessile endoscopic appearance of the index AA/TSA/ASSA were significantly associated with an increased risk for CRC development at a different site.
Recognition that CRC may develop following AA/TSA/ASSA removal is one step toward improving our practice efficiency and preventing a portion of CRC related morbidity and mortality.
Core tip: Screening colonoscopy reduces colorectal cancer morbidity and mortality risks through detection and treatment of precursor lesions. However, screening colonoscopy has a 3.5% false negative rate for detection of colorectal cancer (CRC) resulting in 17% of patients who had undergone colon screening within 3 years being diagnosed with CRC. We report that 3% of patients with advanced polyps in a surveillance program developed interval CRC. Recognition that CRC could develop following advanced polyp removal despite adherence to guidelines is one step toward improving our practice efficiency and preventing a portion of CRC related morbidity and mortality.