Histopathologie des adénomes et cancers colorectaux superficiels: que devrait connaître un endoscopiste à ce sujet?
Histopathology of adenomas and early colorectal cancers: what should an endoscopist know about it?
Colorectal cancer is a major cause of morbidity and mortality worldwide. It is now well established that most colorectal carcinomas arise from adenomas. Such lesions present many different microscopic features as tubulous, villous or serrated adenomas and are characterized by intraepithelial neoplasia with different degrees of severity. In some conditions such as inflammatory bowel diseases, precursor lesions and their management are slightly different from those occurring in sporadic cases.
Early colorectal cancer is an invasive lesion limited to the submucosa (pathologic T category p T1 in the TNM classification.
Macroscopically, early colorectal cancer and its precursor lesions present as elevated polyps or flat lesions. It can be treated by endoscopic resection. Nevertheless, careful handling of the specimen is required in order to optimally identify the factors which may predict an adverse outcome (lymph node metastasis, residual tumour…) which should lead to laparotomy. Because precursor lesions are not necessarily homogeneous, the entire lesion should be removed and examined. Simple biopsies are not reliable.
Anne JOURET, K. GEBOES
adenoma, DALM, early colorectal carcinoma, flat adenoma, intraepithelial neoplasia, serrated polyp