Abstract: Background and purpose: Alpha fetoprotein (AFP)-producing gastric cancer (AFPGC) is considered to be a special type of gastric cancer. Currently, the effect on AFPGC is not as good as the common AFP-negative gastric cancer. Therefore, it is very important to explore clinicopathological features of AFPGC cancer, to improve diagnosis and individualized treatment. This study is to investigate the expressions of hepatocyte growth factor receptor c (c-Met), vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER-2) in the AFPGC. Methods: A total number of 44 cases of AFPGC (serum AFP≥10 μg/L) tissues were selected as a test group. There were 30 cases of serum AFP≥200 μg/L. This study collected 30 cases of gastric cancer with normal AFP and 30 cases of hepatocellular carcinoma with increased AFP (serum AFP≥200 μg/L) as 2 control groups. The cases of the 3 groups had the same clinical stage basically. The expressions of c-Met, VEGF, EGFR and HER-2, CD34 were detected by immunohistochemistry (EnVision staining method). Tumor microvessel density (MVD) was calculated by marking CD34, and the results were analyzed. The clinicopathologic parameters were recorded accurately: gender, age, highest level of serum AFP, tumor differentiation, tumor stage, tumor location, lymph node metastasis, liver metastasis, Lauren classification, etc. These patients were followed up regularly. The clinical pathological features of AFPGC patients were investigated. Results: AFPGC clinical characteristics showed that, among 44 cases of AFPGC group, 86.36% (38/44) had lymph node metastasis, 54.55% (24/44) had hepatic metastasis, intestinal type was 36.36% (16/44), diffuse type was 56.82% (25/44), mixed type was 6.82% (3/44). The positive expression rates of c-Met protein in AFPGC, gastric cancer with normal AFP, hepatocellular carcinoma with increased AFP were 73.33% (22/30), 70.00% (21/30) and 53.33% (16/30), respectively. The positive expression rates of VEGF protein were 76.67% (23/30), 56.67% (17/30) and 66.67% (20/30), respectively. The positive expression rates of EGFR protein were 53.33% (16/30), 40.00% (12/30) and 73.33% (22/30), respectively. The “++ and +++” expression rates of HER-2 in AFPGC, gastric cancer with normal AFP and hepatocellular carcinoma with increased AFP were 38.64% (17/44), 23.33% (7/30) and 26.67% (7/30), respectively. The MVD values in AFPGC, gastric cancer with normal AFP and hepatocellular carcinoma with increased AFP were 23.03±10.24, 21.92±11.45 and 19.43±7.83, respectively. Compared with gastric cancer with normal AFP, expression of VEGF protein was significantly higher in the AFPGC (P<0.05). Compared with hepatocellular carcinoma with increased AFP, the expression of c-Met protein was significantly higher in AFPGC (P<0.05). Conclusion: AFPGC is prone to lymph node metastasis and hepatic metastasis. The major part is the diffuse type in Lauren classification. The positive expression rates of VEGF protein in AFPGC were significantly higher than the gastric cancer with normal AFP. The positive expression rates of c-Met protein in AFPGC were significantly higher than the hepatocellular carcinoma with AFP increased.

Key words: Gastric carcinoma, Alpha fetoprotein, Vascular endothelial growth factor, c-Met