HER2 expression in renal cell carcinoma

Abstract

Renal cell carcinoma (RCC) is the most common malignancy of the adult kidney. A variety of proteins have been investigated for their use as prognostic tumor markers. At present, there are conflicting reports concerning HER2 expression in RCC. PURPOSE: The aim of this study is to evaluate the expression of HER2 protein in patients with renal cell carcinoma (RCC) and to determine the relationship between the tumor grading, staging and the type of the tumor. METHODS: The expression of HER2 in renal cell carcinoma was studied using immunohistochemical methods in paraffin-embedded specimens from 34 patients. Of these cases, 19 patients had clear cell carcinoma, 6 had chromophobe, 5 had papillary, and 4 had urothelial renal carcinoma. Nine of the patients had metastases (in regional lymph nodes and distants), 25 patients were without metastases. The membranous staining of HER2 was assessed as positive when the score was higher than 2 (0, 1 – negative, 2, 3 – positive), according to the well accepted scoring system for breast cancer. RESULTS: The results showed that there were varying degrees of HER2 expression in different RCC’s histological types. The same changes in HER2 expression can be seen in the tumors with and without metastases. There was no significant association between HER2 overexpression and tumor stage, grade and the type of tumor. The results of the present study point out the necessity to discuss eventual beneficial effect of Herceptin therapy.