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．

目的 探讨直肠神经内分泌肿瘤的临床病理特征。方法 回顾性分析46例直肠神经内分泌肿瘤患者的临床病理资料,对不同病理分级的患者在性别、年龄、肿瘤直径、浸润深度、肝及淋巴结转移等方面进行比较。结果 直肠神经内分泌肿瘤男性多见,肿瘤多位于直肠中下段。免疫组化检测显示CgA、Syn、CD56阳性率分别为40.0%、97.8%、100%。36例Ki-67阳性指数≤2％,6例Ki-67阳性指数在3％～20％,4例Ki-67阳性指数＞20％。不同病理分级的肿瘤与患者年龄、肿瘤直径、浸润深度、淋巴结及肝转移相关,与性别不相关。结论 直肠神经内分泌肿瘤缺乏临床特异性症状,联合CgA、Syn和CD56染色可提高直肠神经内分泌肿瘤的诊断率。病理分级对预测肿瘤浸润深度、肝或淋巴结转移有重要参考价值。

Objective To investigate the pathological and clinical significance of 46 cases of rectal neuroendocrine tumors(NET). Methods Retrospectively analyzed the clinical and pathological feature of 46 patients with rectal NET, and assessed possible interactions between different pathological grades and gender, age, tumor diameter, depth of invasion, lymph node and liver metastasis. Results Rectal NET appeared more frequently in males than in females. Most tumors located in middle and distal third of rectum. The positivity rates of immunohistochemical marker CgA, Syn, CD56 were 40.0%, 97.8%, 100.0%, respectively. The cases of Ki-67 positivity rate under 2%, ranged between 3%-20%, above 20% were 36, 6, 4, respectively. Different pathological grades were significantly correlated with age, tumor diameter, depth of invasion, lymph node and liver metastasis, but not with gender. Conclusion Rectal NET had nonspecific symptoms. Combined immunohistochemical staining, such as CgA, Syn and CD56, was important in the evaluation of rectal NET. Pathological grading might be very useful for prediction of invasion depth, lymph node and liver metastasis.