Expression of pRb, Ki67 and HER 2/neu in gastric carcinomas: Relation to different histopathological grades and stages.

Gastric carcinoma is one of the aggressive malignancies with poor prognosis. The expression of pRb, Ki67, Her-2 in relation to tumor grade and stage in gastric carcinoma still needs more exploration. This study was performed aiming to study the immunohistochemical expression of altered retinoblastoma encoding protein (pRb), Ki67 and Her-2 in gastric carcinoma and to investigate their clinical and pathological significance. We studied tumor tissue specimens from 48 patients with gastric carcinoma. Paraffin sections were submitted for immunohistochemistry using pRb, Ki67 and Her-2. Statistical analysis was performed for clinical and pathological data of all studied cases. Altered pRb was expressed in 79% of the studied tumors, inversely correlated with tumor invasion and stage with no significant relation with tumor grade, age, and gender and tumor size. Ki67 LI was significantly associated with tumor grade and stage but not related to sex, age, tumor size, site, depth of invasion and lymph node metastasis. Her2 was expressed in 75% of studies tumors with significant association with tumor grade, the depth of invasion, lymph node metastasis and higher tumor stage. However, there was no significant association between Her-2 expression and gender, tumor site and size. In conclusion, altered pRb is frequently expressed in gastric carcinoma, inversely correlates with tumor invasion and tumor stage suggesting an early event in gastric carcinogenesis. Ki67 expression in gastric carcinoma is directly correlated with the tumor grade and depth of invasion. Her2 expression is significantly correlated with tumor grade, depth of invasion and stage.