Immunohistochemical and Histopathological Study of Anaplastic Lymphoma Kinase and Tyrosine-kinase Receptor Expression in Bronchogenic Carcinoma

Abstract

BACKGROUND: Adenocarcinoma of the lung is the most common tumor type of primary lung cancer and is characterized by heterogeneity on the molecular, clinical, and pathological levels. The presence of an anaplastic lymphoma kinase (ALK) fusion oncogene defines a molecular subset of non-small cell lung cancer with distinct clinical and pathologic features. Furthermore, the tyrosine-kinase receptor (C-kit) is considered to be expressed in various solid tumors, including carcinomas of the lung. AIM: This study aims to correlate immunohistochemical (IHC) expression of ALK and C-kit with pathological features of lung carcinoma and to correlate IHC expression of ALK with IHC expression of C-kit in lung carcinoma. MATERIALS AND METHODS: The material of this study consists of paraffin blocks of 60 cases of patients with bronchogenic carcinoma, IHC staining with ALK and C-kit then analysis of immunoreactivity scoring was done. RESULTS: As regards ALK expression, 3 (5%) cases showed positive expression of ALK and 57 (95%) cases showed negative expression of ALK with no statistically significant correlation between the ALK expression and the histopathological type. While C-kit expression, 4 (6.7%) cases showed positive expression and 56 (93.3%) cases showed negative expression of C-kit with statistically significant correlation between the C-kit expression and the histopathological type. CONCLUSION: There is an association between expression of c-kit and tumor histological type in lung carcinoma. Expression was notably significant among adenocarcinomas and small cell carcinomas.