PS02.090: WHY BARRETT’S ESOPHAGEAL ADENOCARCINOMAS WERE FOUND AS WIDE LESIONS

Abstract Background Barrett's esohageal adenocarcinoma(BEA) originated from Long-segment Barrett's esophagus(LSBE) were found to be larger lesions than BEA from Short-segment Barrett's esophagus(SSBE). In Japan, superficial BEA were found and treated by ESD. However, most of superficial BEA in Japan are originated from SSBE. We investigated about the differences between BEA from SSBE and LSBE. Methods We examined macroscopic appearance and histology for superficial BEA. And we compared with BEA between SSBE and LSBE.And then we examined imminohistochemical study using p53 for operated specimens of superficial BEA. Results The multiple lesions were presented only LSBE cases. Operations were the far more common treatment for LSBE. The ratio of lesions involving more than one-half of the lumen was significantly larger in LSBE cases. The percentage of type 0-IIb was only 3.2%(3/95) for SSBE, whereas 32.6%(15/46) for LSBE (P < 0.05). When we placed each macroscopic type into one of two groups (Elevated and Flat or depressed type), we found that elevated types accounted for 63.2%(60/95) in SSBE cases. In LSBE cases, 50.0%(23/46) were of the flat or depressed type. In SSBE, simple macroscopic types accounted for 69.5%(66/95). Whereas, in LSBE cases, 50.0%(23/46) were of complex macroscopic types (P < 0.05). The lesions with accompanied type 0- IIb accounted for 2.1%(2/95) of SSBE and 21.7%(10/46) of LSBE(P < 0.05). The more common macroscopic type of T1b invasion was type 0- IIa +  IIc. p53 immunohistochemical study was done for an operated specimen. This case was operated for superficial BEA. p53 was strongly positive on adenocarcinoma. However, we could find p53 strongly positive part on other part of the specimens. There were three part of p53 positive are in this operated specimens. These parts were not defined adenocarcinoma by HE stained. Conclusion Most superficial BEA originated from SSBE could be distinguished by the elevated lesions. Whereas, in cases of LSBE, flat type lesions including the accompanied type 0- IIb and multiple lesions, operation cases, the ratios of lesions involving a large range and the complex macroscopic types were significantly higher. When we diagnose and treat superficial BEA, it is necessary to consider the differences between SSBE and LSBE, such as macroscopic types. Disclosure All authors have declared no conflicts of interest.