Roel Bogie

Chapter 9

Abstract Introduction

Post-colonoscopy colorectal cancers (PCCRCs) are considered to be a crucial quality outcome measure for colonoscopy. PCCRCs may occur due to various reasons such as non-adherence to surveillance intervals, inadequate bowel examination, incomplete polyp resection, missed lesions or newly developed cancers. Recent studies indicate that non-polypoid colorectal neoplasms (NP CRNs) and serrated lesions, which are smaller and more easily overlooked during colonoscopy, may be important precursor lesions of PCCRC. The present study was undertaken to investigate whether systematic training in detection and resection of NP-CRN reduces the PCCRC rate. Methods In the Maastricht UMC+, all endoscopists were systematically trained in 2008 to optimize detection and resection of NP-CRNs. PCCRCs found after colonoscopy performed 4 years before and 4 years after training were included. For PCCRC identification, we used follow-up data until 2014. Results After training the PCCRC rate decreased by more than 50% from 2.0 per 1000 colonoscopies to 0.8 per 1000 colonoscopies. Of the 11 PCCRCs found after training, 45% was associated with missed lesions, 18% due to non-adherence to surveillance intervals, 18% due to newly developed CRC, 18% due to inadequate bowel examination and none due to incomplete polyp resection. Conclusion Systematic training in detection and resection of NP-CRNs appears to be able to reduce the PCCRC rate. However, to further minimize the PCCRC rate a multifactorial approach is needed, where training, but also adherence to surveillance intervals and employing quality indicators for colonoscopy are of importance.

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