Immunohistochemical Profile of Lung Tumors in Image Guided Biopsies

Background: Lung cancer is the leading cause of cancer related mortality in both men and women worldwide. Establishing the histological type and grade of pulmonary carcinoma is very important especially for the therapy and prognosis. Study design: cross-sectional descriptive study. The study analyses various histomorphological patterns of lung tumors in correlation with immunohistochemical profile.Methods: All the bronchoscopic and CT guided needle biopsy specimens (50 biopsy specimens) received in the Pathology department of Coimbatore medical college hospital over a period of one year were analysed. Both H&E and immunohistochemical sections were studied with panel of markers- CK7, CK20, TTF-1, chromogranin, synaptophysin, CD45, vimentin, smooth muscle actin.Result: The most common histological type was squamous cell carcinoma (48%), followed by adenocarcinoma (28%) and small cell lung carcinoma (18%). Large cell neuroendocrine carcinoma and metastatic deposit constituted 2% each. Out of 50 cases, 24 cases were squamous cell carcinoma which showed positivity with HMWCK (20 cases) and P63 (22 cases) (p<0.001). Fourteen cases reported as adenocarcinoma showed positivity with CK7 (14 cases) and TTF-1 (13 cases) (p<0.001). All the nine cases of small cell carcinomas showed positivity with both TTF-1 and Ki 67. One case of large cell carcinoma with neuroendocrine features showed immunopositivity with neuroendocrine markers.Conclusion: Integration of conventional histomorphological diagnosis with panel of immunohistochemical markers allows more accurate identification of histological type, which has significant treatment implications. DOI: 10.21276/APALM.1342