2型糖尿病患者易罹患结直肠癌，若接受胰岛素治疗，则不仅结直肠癌发病率更高，且肿瘤进展更加迅速。高胰岛素血症假说认为,异常增高的胰岛素及游离胰岛素样生长因子-1水平可促进结肠细胞增殖,最终导致结直肠癌的发生。由于结直肠癌可通过筛选试验得以早期发现,故建议2型糖尿病患者均应选择合适的筛选形式，特别是接受胰岛素治疗的患者应建议进行结肠镜检查，并且筛选间隔时间不得超过5年。

Colorectal cancer occurs more frequently in patients with Type 2 diabetes mellitus. If patients are treated with insulin, the rate of colorectal cancer would be higher, and the tumor progression would be even more rapid. The hyperinsulinemia-hypothesis suggests that the elevated levels of insulin and free IGF-1 could promote the proliferation of colon cells, and ultimately result in colorectal cancer. Because colorectal cancer can be early detected by screening tests, all patients with Type 2 diabetes mellitus should be recommended to choose appropriate screening modality. In particular, the patients, who are under insulin treatment, should routinely undergo colonoscopy and the screening intervals should not exceed 5 years.

湖南省自然科学基金

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