Relationship between Her2 oncoprotein and microvessel density (MVD) in different histological types of gastric adenocarcinoma

Background: Gastric adenocarcinoma is the fifth most common cause of cancer worldwide and sixth most common cancer in Bangladesh. So, it is important to predict the biological behavior of gastric adenocarcinoma to predict the prognosis and select the appropriate treatment. Her2 and MVD correlate with clinical outcomes in many human tumors including gastric adenocarcinoma. Malignant tumors associated with decreased Her2 expression and increased MVD tend to show worse prognosis. The purpose of the present study is to explore the correlation between Her2 amplification and microvessel density in patients with gastric adenocarcinoma. Methods: This cross-sectional study was carried out in the Department of Pathology, Satkhira Medical College, Satkhira, from August 2022 to July 2024, to evaluate the relationship between Her2 and microvessel density in gastric carcinoma. Fifty cases of invasive gastric adenocarcinoma were included in this study. Specimen were processed routinely for Hematoxylin and Eosin stain. Her2 immunostaining and CD31 immunostaining for microvessel were done following standard protocol. Histopathological results were analyzed, and statistical analysis was done using Statistical Package for Social Science version twenty-eight. Results: Among the fifty cases of gastric adenocarcinomas, 15 (30%) were Her2 positive (3+) and 35 (70%) were Her2 negative. Positive Her2 expression was higher in 78.6% of intestinal type of gastric adenocarcinoma whereas diffuse type showed Her2 positivity in 21.4% cases which was not statistically significant (p-value >0.05). High MVD was found in 18 (58.1%) cases of intestinal type of gastric adenocarcinoma and in only 07 (36.8%) cases of diffuse type of gastric adenocarcinoma. The MVD count in Her2-positive gastric cancer was significantly higher than that in Her2-negative gastric cancer, (P < 0.001). 93.3% of Her2 positive cases demonstrated high MVD, in contrast 68.6% Her2 negative cases showed high MVD (P <0.001). Conclusion: These results indicated that intestinal type of gastric adenocarcinoma with positive Her2 expression exhibited higher CD31 positive angiogenesis implying aggressive biological behaviors. So, it would be a reasonable approach to consider Her2 and CD31 simultaneously as target of gastric cancer treatment.