目的 探讨近端和远端结直肠无蒂锯齿状病变在临床和内镜特征上的区别。方法 回顾性分析103例结直肠无蒂锯齿状病变患者的临床内镜资料,对近端和远端结直肠无蒂锯齿状病变患者在性别、年龄、内镜特征（息肉大小、山田分型、内镜NICE分型、蛇形微血管、黏液帽）等方面进行比较。结果 与远端结直肠无蒂锯齿状病变相比,近端结肠无蒂锯齿状病变发病年龄更早（P=0.014）,内镜下山田1型息肉更为常见（P=0.050）,黏液帽也是近端结肠无蒂锯齿状病变的重要内镜特征（P<0.001）。结论 近端无蒂锯齿状病变内镜下扁平隐匿,容易漏诊,掌握其内镜特征有助于提高该病的检出率。

Objective To explore the differences in clinical and endoscopic characteristics of sessile serrated lesions in the proximal and distal colorectum．Methods The clinical endoscopic data of 103 patients with sessile serrated lesions of the colorectum were retrospectively analyzed．The gender,age and endoscopic features（polyp size,Yamada classification,NICE classification,dilate vessels and the mucus cap）of patients with proximal and distal colorectal sessile serrated lesions were compared retrospectively．Results Compared with distal colorectal sessile serrated lesions,the age of onset of proximal colon sessile serrated lesions was earlier（P=0.014）,endoscopic Yamada type 1 polyps were more common（P=0.050）,and mucus cap was also an important endoscopic feature of proximal colon sessile serrated lesions（P<0.001）．Conclusions The proximal sessile serrated lesions are flat and hidden under endoscopic examination which are easily missed．Understanding their endoscopic characteristics can help improve the detection rate of the disease．