[Technical review of advanced diagnostic endoscopy in patients at high risk of colorectal cancer]

Hereditary colorectal cancer syndromes

SUMMARY Colorectal cancer (CRC) is one of the most common malignancies and the second-leading cause of cancer death in both sexes in developed countries. Over the last 25 years, highly penetrant monogenic germline mutations that predispose to CRC and other digestive tumors have been identified, accounting for up to 5% of all CRC cases. Identification and characterization of these disorders have allowed modification of their natural history, with a substantial decrease in morbidity and mortality among high-risk patients. Recognizing hereditary CRC has also impacted predictive genetic testing and personalized medicine based on genomic information. This review summarizes the current knowledge on hereditary CRC regarding pathogenesis, clinical features, diagnostic evaluation and management recommendations.

Overcoming challenges in IBD management: management of colonic dysplastic lesions

The aim of any screening or surveillance program must be to identify early lesions to enable treatment and prevention before the development of invasive cancer. A surveillance program must be acceptable to patients and practically possible to implement. There is a move away from using random colonic biopsies towards targeted biopsies aimed at abnormal areas identified by newer colonoscopic techniques (narrow band imaging, chromoendoscopy, confocal microendoscopy). However, the attitude towards a patient with a dysplastic lesion is not well established. Bowel cancer screening in the general population relies on identification of adenomatous lesions which can be resected before they transform into carcinoma. The therapeutic approach to such lesions, the patient groups at risk and the intervals of surveillance are reasonably established. In contrast, inflammatory bowel disease (IBD)-colorectal cancer (CRC) poses different challenges: dysplastic lesions do not follow the adenoma-carcinoma sequence, they can be difficult to see (flat lesions), difficult to resect completely, and multifocal. Prophylactic proctocolectomy eliminates the risk of CRC, but this strategy is not acceptable to most patients or physicians. Moreover, IBD patients can harbor dysplastic lesions related to the sporadic CRC pathway, the clinical significance of which differs clearly from colitis-associated dysplastic lesions. Nowadays, therapeutic recommendations for the management of dysplasia in IBD are based on macroscopic pattern and microscopic characteristics. As an example, consensus guidelines state that adenoma-like lesions can be adequately treated by polypectomy unlike non-adenoma-like raised lesions or flat high-grade dysplasia that should undergo colectomy. The present article is aimed to summarize the existing evidence on this thorny matter.