Histopathological study and immunohistochemical expression of epidermal growth factor receptor in lung tumours - a hospital based study at kles dr. Prabhakar kore hospital & mrc, belagavi.

Abstract

Background & Objectives: Currently, lung cancer is the commonest etiology for cancer mortality in world. In the present-day scenario, it is one of the major cancers diagnosed frequently. Lung cancer has proven to kill more patients compared to those suffering from breast, colon and prostate cancers combined. Statistically, for 1.8 million deaths reported due to lung cancer, out of estimated 2.1 million new cases formed in year 2018, lung cancer stands out to be a major cause of mortality worldwide. As most of the lung cancers are in advanced stage of disease at the time of diagnosis, screening attempts have to be developed in future so that the cancer can be identified for the better outcome and prognosis. Adenocarcinoma is now the most common form of cancer compared to squamous cell carcinoma and small cell carcinoma of the lung. Till a decade ago, EGFR mutation analysis by direct sequencing was studied and was a dependable method to predict response to TKIs. Further, it was studied that both EGFR mutation and gene amplification status were essential to know which tumours will respond to TKIs. In 2015, an Indian study was conducted for evaluation of EGFR expression by IHC method, which concluded that EGFR expression is associated with a 6 month survival post chemotherapy. It was also concluded that overexpression (H-score>200) was associated with poor prognosis. The arrival of successful molecular targeted therapies which are directed at specific cell types as well as subtypes, has augmented the need for a more particular subtyping and classification of these cancers. Hence, the present study is being conducted to study histopathological spectrum of lung cancer types and EGFR expression by IHC.