Endoscopic submucosal dissection for undifferentiated-type early gastric cancer: Do we have enough data to support this?

Although endoscopic submucosal dissection(ESD)is now accepted for treatment of early gastric cancers(EGC)with negligible risk of lymph node(LN)metastasis,ESD for intramucosal undifferentiated type EGC without ulceration and with diameter≤2 cm is regarded as an investigational treatment according to the Japanese gastric cancer treatment guidelines.This consideration was largely based on the analysis of surgically resected EGCs that contained undifferentiated type EGCs;however,results from several institutes showed some discrepancies in sample size and incidence of LN metastasis.Recently,some reports about the safety and efficacy of ESD for undifferentiated type EGC meeting the expanded criteria have been published.Nonetheless,only limited data are available regarding long-term outcomes of ESD for EGC with undifferentiated histology so far.At the same time,endoscopists cannot ignore the patients’desire to guarantee quality of life after the relatively non-invasive endoscopic treatment when compared to conventional surgery.To satisfy the needs of patients and provide solid evidence to support ESD for undifferentiated EGC,we need more delicate tools to predict undetected LN metastasis and more data that can reveal predictive factors for LN metastasis.

Impact of tumor location on clinical outcomes of gastric endoscopic submucosal dissection

AIM:To determine whether there is a correlation between the location of the lesion and endoscopic submucosal dissection(ESD)outcome.METHODS:From January 2008 to December 2010,ESD of 1443 gastric tumors was performed.En bloc resection rate,complete resection rate,procedure time and complication rate were analyzed according to the tumor location.RESULTS:The rates of en bloc resection and complete resection were 91%(1318/1443)and 89%(1287/1443),respectively.The post-ESD bleeding rate was 4.3%,and perforation rate was 2.7%.Tumors located in the upper third of the stomach were associated with a longer procedure time and significantly higher rates of incomplete resection,piecemeal resection,and perforation than tumors below the upper third of the stomach.Posterior wall lesions had significantly longer procedure times and higher rates of incomplete resection and piecemeal resection than lesions in other locations.In multivariate analysis,posterior wall lesions and upper third lesions were significantly associated with incomplete resection and perforation,respectively.In post-ESD bleeding analysis,location was not a significant related factor.CONCLUSION:More advanced endoscopic techniques are required during ESD for lesions located in the upper third or posterior wall of the stomach to decrease complications and improve therapeutic outcomes.