Gastric ESD may be useful as accurate staging and decision of future therapeutic strategy.

We sometimes perform gastric endoscopic submucosal dissection (ESD) for total pathologic diagnosis when preoperative diagnosis is difficult. In the present study we analyzed the treatment outcomes and adverse events of diagnostic ESD for early gastric cancer (EGC).  We conducted a retrospective analysis of 18 consecutive cases of EGC in 18 patients with a suspected out-of-indication diagnosis who underwent diagnostic ESD, between June 2010 and November 2014. The following parameters were examined: the average length of the longer axis of the lesion; the procedure time; the rates of en bloc resection (ER), complete en bloc resection (CER), and curative resection (CR) as treatment outcomes; and the rates of perforation, delayed bleeding, aspiration pneumonia, disease-related death, and emergency surgery as adverse events. The treatment outcomes were as follows: average length of the longer axis of the lesion, 27.4 ± 10.0 mm; procedure time, 87.0 ± 43.1 minutes; ER rate, 18/18 (100.0 %); CER rate, 13/18 (72.2 %); CR rate, 4/18 (22.2 %). CR rate was achieved 37.5 % for the lesions which preoperative diagnosis was more than 30 mm (> 30 mm) in diameter differentiated type with mucosal layer/submucosal layer 1 invasion and ulceration positive. The adverse events (AEs) were perforation in 1 of 18 (5.5 %) patients and delayed bleeding in 1 of 18 (5.5 %). There were no other AEs. Diagnostic ESD may be acceptable for future therapeutic strategy when we unconfirmed the pre ESD diagnosis because of lower rate of adverse events and high rate of ER.