Pathobiological characteristics of intestinal and diffuse-type gastric carcinoma in Japan: an immunostaining study on the tissue microarray

AIM: To investigate the pathobiological features of intestinal and diffuse-type gastric carcinomas in the Japanese population. METHODS: The expression of fragile histine triad (FHIT), phosphatase and tensin homology deleted from human chromosome 10 (PTEN), caspase-3, Ki-67, mutant p53, matrix metalloproteinase (MMP)-2, MMP-9, and extracellular matrix metalloproteinase inducer (EMMPRIN) on tissue microarrays of gastric carcinomas by immunostaining was examined in comparison with the clinicopathological characteristics between intestinal and diffuse-type cases. RESULTS: Intestinal-type carcinoma frequently occurred in old men, whereas the diffuse type comparatively occurred more in young women (p<0.05). The diffuse-type carcinoma was more inclined to invasion into muscularis propria, lymphatic invasion and lymph node metastasis, and belonged to higher International Union against Cancer (UICC) staging (p<0.05) compared with intestinal-type counterparts. Expression of FHIT, PTEN, Ki-67, caspase-3, mutant p53 and EMPPRIN was higher in intestinal-type carcinomas than in diffuse-type carcinomas (p<0.05). Kaplan-Meier analysis indicated that patients with intestinal-type carcinomas had a higher cumulative survival rate (p<0.05). CONCLUSION: Intestinal-type gastric carcinomas with a more favourable prognosis frequently show high levels of proliferation and apoptosis, and always accompany strong expression of FHIT, PTEN and mutant p53 and EMMPRIN. EMMPRIN expression might underlie the molecular basis of liver metastasis and higher proliferation of intestinal-type gastric carcinomas in Japan. Lauren's classification thus proved pathologically relevant for the clinical treatment of gastric carcinomas.