直肠癌的致病因素很多,近年来认为直肠部分之息肉恶变是主要原因之一。息肉有单发或多发,有遗传性或非遗传性,直肠息肉在组织学上大多为肿瘤性,但也含有多种疾病,故息肉不是某一疾病特定的专一名词,而是突出于肠粘膜表面任何病变的总称。直肠息肉可势为:①新生物性,②化生性,③炎 There are many pathogenic factors of rectal cancer. In recent years, malignant transformation of polyps in the rectum is considered to be one of the major causes. Polyps have single or multiple, heritable or non-genetic, rectal polyps are mostly neoplastic in histology, but also contain a variety of diseases, so polyps are not specific to a specific disease, but prominent in the intestine The general name of any lesion on the mucosal surface. Rectal polyps can be: 1 new biological, 2 metaplastic, 3 inflammation