Collett J A, Platell C, Fletcher D R, Aquilia S, Olynyk J K
Department of Gastroenterology, Fremantle Hospital, Western Australia, Australia.
J Gastroenterol Hepatol. 1999 Jan;14(1):67-71. doi: 10.1046/j.1440-1746.1999.01804.x.
Flexible sigmoidoscopy has been recommended as a screening method to reduce the incidence of colorectal cancer in asymptomatic, average-risk subjects through the early detection and removal of polyps. However, the association between distal and proximal colonic neoplasia and, hence, the requirement for colonoscopic follow up of screen-detected distal neoplasms is unclear. Our aims were: (i) to evaluate the risk of having proximal neoplasms in those with distal colonic neoplasms; and (ii) to determine whether the risk was dependent on the number, size, histology or morphology of the distal lesions. We prospectively evaluated asymptomatic subjects in a flexible sigmoidoscopy based screening programme. Those with rectosigmoid neoplasia underwent colonoscopy. The number, size, histology and morphology of the polyps were recorded. Advanced lesions were defined as adenomas > 1 cm or with a villous component or severe dysplasia, carcinoma in situ or cancer. Adenomatous polyps were found in 17% (135) of screening flexible sigmoidoscopies. At colonoscopy, up to 30% of subjects with distal colonic neoplasms had synchronous proximal lesions at colonoscopy and up to 20% had advanced proximal lesions. The risk of proximal colonic neoplasia was increased in those with distal sessile colonic neoplasms but appeared independent of distal lesion size, number or morphology. In conclusion, distal colonic neoplasia predicts proximal neoplasia in up to 30% of subjects and these were advanced lesions in up to 20%. We recommend that all subjects with biopsy proven distal colonic neoplasia undergo colonoscopy.
柔性乙状结肠镜检查已被推荐作为一种筛查方法，通过早期发现和切除息肉来降低无症状、平均风险人群患结直肠癌的发病率。然而，远端和近端结肠肿瘤之间的关联，以及因此对筛查发现的远端肿瘤进行结肠镜随访的必要性尚不清楚。我们的目的是：（i）评估患有远端结肠肿瘤的患者发生近端肿瘤的风险；（ii）确定该风险是否取决于远端病变的数量、大小、组织学或形态。我们对一个基于柔性乙状结肠镜检查的筛查项目中的无症状受试者进行了前瞻性评估。患有直肠乙状结肠肿瘤的患者接受了结肠镜检查。记录息肉的数量、大小、组织学和形态。高级别病变定义为腺瘤>1 cm或具有绒毛成分或重度发育异常、原位癌或癌。在17%（135例）的筛查柔性乙状结肠镜检查中发现了腺瘤性息肉。在结肠镜检查中，高达30%的远端结肠肿瘤患者在结肠镜检查时有同步近端病变，高达20%的患者有高级别近端病变。患有远端无蒂结肠肿瘤的患者发生近端结肠肿瘤的风险增加，但似乎与远端病变的大小、数量或形态无关。总之，远端结肠肿瘤在高达30%的患者中预示着近端肿瘤，其中高达20%为高级别病变。我们建议所有经活检证实患有远端结肠肿瘤的患者都应接受结肠镜检查。
