C-kit (CD117) Expression Is Not Valuable to Predict Prognosis in Invasive Ductal Carcinoma of Breast

Abstract

Objective: C-kit functions as a tyrosine kinase receptor and represents a target for small molecule kinase inhibitors. The expression pattern for c-kit was studied in different human tumor types as gastrointestinal stromal tumor, malignant melanoma, breast and lung cancer, sarcoma and mastocytosis. C-kit expression in malignant tumors can be a factor that might affect the prognosis and its expression in different tumors was studied in respect of its correlation with the outcome. Imatinib or sunitinib therapy of KIT-positive tumors is an example of a targeted cancer therapy requiring immunohistochemical tumor analysis to identify patients that would benefit from this kind of therapy. This study is done on patients with breast cancer to find out the frequency of c-kit expression and to find out if it has any effect on the outcome of the patients and to compare the results with that of other ethnicities. Materials and Methods: Paraffin-embedded tumor tissues from 81 patients with breast invasive ductal carcinoma were analyzed immunohistochemically for c-kit expression and correlated to the survival of the patients after initial diagnosis using the follow-up data. Results: The mean age of the patients was 52.8 years. The median follow-up period was 22 months (range 1-37 months). C-kit immunopositivity was found in 37 cases (46%). Expression of c-kit was found in tumor samples with varying intensities and infrequently. Conclusion: There was no significant correlation between c-kit expression and prognosis.