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Risk factors for postoperative stricture after endoscopic submucosal dissection for superficial esophageal carcinoma.

BACKGROUND AND STUDY AIMS
Endoscopic submucosal dissection (ESD) is accepted as an established treatment modality for superficial esophageal carcinoma (SEC). The aim of this study was to identify risk factors for postoperative stricture after ESD for SEC.


PATIENTS AND METHODS
This was a retrospective study at a single institution. A total of 362 patients with SEC treated by ESD at Zhongshan Hospital, Shanghai, were enrolled between January 2007 and February 2012. Demographic and clinical parameters, including patient-, lesion-, and procedure-related factors, were analyzed for postoperative stricture risk factors.


RESULTS
The postoperative stricture rate was 11.6 % (42/362). The mean and median time from ESD to stricture was 58.5 ± 12.3 days (range 21 - 90 days) and 28 days, respectively. Mild, median, and severe stricture were observed in 16.7 % (7/42), 38.1 % (16 /42), and 45.2 % (19/42) of patients, respectively. Multivariate analysis revealed that circumferential extension of > 3/4 (odds ratio [OR] 44.2, 95 % confidence interval [CI] 4.4 - 443.6) and the depth of invasion above m2 (OR 14.2, 95 %CI 2.7 - 74.2) were independent risk factors for stricture. The degree of stricture was also related to lesion circumferential extension (relational coefficient φ = 0.47; P < 0.05) and histological depth (relational coefficient φ = 0.647; P < 0.05).


CONCLUSIONS
Circumferential extension and histological depth were reliable risk factors for postoperative stricture.