Frequency of c-Met, HGF, and HER-2 expression and evaluation of their association with clinicopathologic and prognostic factors in gastric cancer.

Abstract

88 Background: Met and HER-2 are protoonkogenes encoding receptor tyrosin kinases c-Met and HER-2 respectively. HGF is c-Met’s ligand. We aimed to determine the frequency of c-Met, HGF and HER-2 overexpression in gastric cancer and investigated their association with clinicopathological factors and prognosis. Methods: Patients withstage 1-4 disease were analyzed. Overexpressions of c-Met, HGF and HER-2 were carried out with immunohistochemistry. Results: A total of 143 patients, 97 male 46 female were enrolled. C-Met score was 3(+) in 31.5%, 2(+) in 27.3% and 1 (+) in 10.5% of the patients. There was no statistically significant difference in age, sex, tumor location, differentiation, Lauren classification, TNM staging, presence of distant metastasis, depth of tumor invasion (T), lymphovascular invasion, and survival between c-Met subgroups. HGF positivity was 20.6%. HER-2 was 3(+) in 9.1%, 2(+) in 9.8%, and 1(+) in 16.1% of the patients. HER-2 overexpression was associated with better differentiation, intestinal subtype and advanced stage. C-Met overexpression was 84.6% in HER-2 overexpression positive group and 56,2% in HER-2 overexpression negative group. There was no statistically significant difference in survival between the c-Met overexpression positive and negative stage 3 and 4 patients and there was no statistically significant differences in survival between the HGF positive and negative groups. The median survival was 11.6±6.3 months in HER-2 overexpression positive stage 4 group and 11.9±6.8 months in HER-2 overexpression negative stage 4 group. There was no statistically significant differences in survival between the two groups. Conclusions: C-Met was not associated with any negative prognostic factors in gastric cancer. HER2 was associated with better differentiation, intestinal subtype, advanced stage and c-met overexpression. HGF expression was not asscociated with any clinicopathological factor.