Role of immunohistochemistry in cell block sections for categorization of non-small cell carcinoma of lung

Background: Computed tomography (CT) guided fine needle aspiration and cytology (FNAC) is a useful modality which aids in early and fairly accurate diagnosis of mass lesions of lungs specially the malignant ones. Previously in patients with primary lung cancer the most important consideration was to discriminate between small cell and non-small cell carcinoma (NSCC) of the lung. With advancement of cancer therapy, sub-typing of NSCC has become very important. The aims of the study were to evaluate the pathological spectrum of the pulmonary diseases in CT guided FNAC of lung mass lesions and utility of limited immunohistochemistry (IHC) in cell block sections to subcategorize NSCC