Objective To observe the expression of cytokeratin 14,15 (CK14,CK15) expression level in normal esophageal tissues and esophageal squamous cell carcinoma tissues of different differentiation degree and to analyze the relationship between occurrence,development of esophageal squamous cell carcinoma and CK14,CK15 expression level.Methods Esophageal squamous epithelial tissue from 55 cases of carcinoma tissues and 55 cases of adjacent tissues were collected.Immunohistochemical method was used to compare CK14,CK15 and PCNA expression levels in esophageal squamous carcinoma.Results Expression positive rates of CK14,CK15 and PCNA in esophageal squamous carcinoma were 72.7 ％ (40/55),63.6 ％ (35/55) and 65.5 ％ (36/55),respectively,and PCNA expression was correlated with CK14 or CK15 expression (C =0.585,P ＜ 0.001; C =0.405,P ＜ 0.001).CK14 and CK15 levels were higher in high differentiation carcinoma tissue than those in low differentiation carcinoma tissue,and PCNA expression level was increased in low differentiated carcinoma tissue.CK14,CK15 and PCNA were expressed located in base layer of esophageal squamous epithelial adjacent to carcinoma tissue,and their expression positive rates were 56.4 ％ (31/55),52.7 ％ (29/55) and 56.4 ％ (31/55).CK14 and CK15 levels were higher in esophageal squamous epithelial tissues of far-cut edge than those in tissues of near-cut edge (intraepithelial neoplasia).There were no associations between CK14,CK15 expression and the clinical parameters (P ＞ 0.05).Postoperative survival time in patients with CK14 or CK15 positive expression was shorter than that of patients with negative expression (P ＜ 0.05).Conclusions CK14 or CK15 positive expressions localized to base layer of esophageal squamous epithelial adjacent to carcinoma tissue may play some roles in generation and differentiation of esophageal squamous cell cancer.CK14 or CK15 positive expression in esophageal squamous carcinoma involves in differentiation process.Joint detection of CK14 and CK15 expression has clinical application value for early diagnosis,the degree of differentiation and prognostic judgment in esophageal squamous carcinoma.

Objective To investigate the clinical efficacy of endoscopic submucosal dissection (ESD)for the treatment of colorectal tumors, and to analyze risk factors affecting operation time. Methods A retrospective study was conducted using data of 74 cases with colorectal tumor,who underwent ESD in Department of Gastroenterology of Wuhan University Renmin Hospital from January 2014 to September 2015. The clinical efficacy of ESD, occurrence of complications and follow-up results were summarized,and the risk factors of operation time were analyzed. Results The rate of ESD en bloc resection and histological complete resection was 97.30%(72/74)and 89.19%(66/74), respectively. Among the 8 cases of histological non-curative resection, 2 cases received appended surgical procedures because of deep invasion of tumor(SM2),6 cases were given close follow-up according to the pathological result of adenomas. Among the 74 cases, no acute hemorrhage or pneumoperitoneum occurred. Four cases (5.41%, 4/74)had postoperative delayed bleeding, and were successfully treated by endoscopic hemostasis. Four cases(5.41%, 4/74)had intraoperative perforation, and were successfully treated by endoscope. No recurrence or abnormal lesions occurred during the follow-up of 15-35 months. Multivariate linear regression analysis showed that tumor size was a main risk factor for ESD operation time(P=0.000). Conclusion ESD, as a minimally invasive treatment, is safe and effective for the treatment of colorectal tumors,and the tumor size is a main risk factor of ESD operation time.