No decrease in the rate of early or missed colorectal cancers after colonoscopy with polypectomy over a 10-year period: A population-based analysis

Background & Aims: It is not clear whether the incidence of missed or early colorectal cancers (CRCs) has decreased over time. We compared the rates of missed or early CRC after polypectomy between 1996 and 2006, and aimed to identify risk factors for these. Methods: We performed a population-based, case-control study linking data from the Dutch Pathology Registry with data from The Netherlands Cancer Registry. Of all patients with an incident CRC in 1996 and 2006, we identified whether colonic histology specimens were available in the preceding 3 years. Patients with early or missed CRC were defined as those with previous colonic histology in the 6 to 36 months preceding CRC diagnosis. We performed multivariate logistic regression analysis to identify factors associated with missed or early CRCs. Results: CRC was diagnosed in 6941 patients in 1996 and in 10,963 patients in 2006. The proportion of patients with early or missed CRC was 1.7% of all CRC patients in 1996 and 2.3% in 2006 ( P= .012). Early or missed CRCs had a lower tumor, nodal, and metastasis stage than regularly diagnosed CRCs ( P < .001), but rate of survival, adjusted for TNM stage, did not differ. CRCs of the right colon and transverse colon and splenic flexure were associated with a missed or early CRC (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.80-3.05; and OR, 2.14; 95% CI, 1.49-3.08, respectively), as was male sex (OR, 1.31; 95% CI, 1.06-1.62). Conclusions: Based on an analysis of the Dutch population, there has been no decrease in the occurrence of missed or early CRCs over a 10-year period. Location in the right side of the colon was an independent risk factor for missed or early CRCs