Examination of NBI magnifying endoscopic findings “irregularity vessel” and histologic type of gastric cancer

We studied 32 patients with gastric lesions whose biopsy specimens showed moderately to poorly differentiated adenocarcinoma and who were treated by ESD from April 2007 to March 2010 at the Cancer Institute Hospital. All patients were observed by NBI magnified endoscopy and en bloc resection was performed. We defined NBI findings of characteristic blood vessels of undifferentiated-type early gastric cancer as “irregular vessels”. We compared the presence of irregular vessels with the histology of ESD specimens. In total, 20 of the 32 patients had irregular vessels, and all 20 cases were of the undifferentiated mixed-type. 6 of the 12 cases that were not observed to have irregular vessels were purely differentiated adenocarcinoma. 12 out of 13 mixed-type cases in which the undifferentiated type was dominant were observed to have irregular vessels (92.3%) . 8 out of 13 mixed-type cases in which the differentiated type was dominant were observed to have irregular vessels (61.5%) . Despite the presence of undifferentiated mixed-type gastric cancer, 6 patients were not observed to have irregular vessels. The reason for this is the narrow area of undifferentiated adenocarcinoma and localization of the undifferentiated adenocarcinoma at a deeper part of mucosa.