Evaluation of ALK, EGFR and PD-L1 Mutations in Pulmonary Carcinomas through Immunohistochemistry

Abstract

Introduction: Lung cancer, with about 2.2 million new cases and 1.8 million deaths, is the second most commonly diagnosed cancer and the leading cause of cancer death in 2020. Immunohistochemistry (IHC) now is used not only to diagnose and classify lung tumors into subtypes, but also to determine the eligibility of patients for different molecular-targeted therapies. Objectives : Study of ALK, EGFR and PD-L1 mutations in Pulmonary Carcinomas through immunohistochemistry examinations to help determine the prognosis and cases that may benefit from target therapy. Detection of possible links between ALK, EGFR, PD-L1 and other variables such as age, sex, histological entity and degree of tumor differentiation. Materials and Methodology: The study is retrospective and includes 266 patients diagnosed with lung cancer who underwent biopsy at the American Hospital in the period 2016-2020. Tissues obtained were subjected to IHC examination using antibodies against factors EGFR, ALK, PD-L1, etc. Results: The study showed that out of 266 patients, 24% of lung cancer cases are females and 76% are males. The average age was 61.8 years. No statistically significant relationship was found between ALK, PD-L1 and EGFR with variables such as age, gender and degree of differentiation of adenocarcinomas. No significant link was found between ALK and PD-L1 and the histological entity, but a significant link was found between EGFR and histological type of pulmonary carcinomas. Conclusions : Lung cancer is one of the most common cancers, found mainly in men, but also in women. Nowadays, IHC helps not only to diagnose lung cancer, but also to determine patients who can respond to target therapy and their prognosis. Therefore, the use of IHC to detect ALK, EGFR, PDL-1 mutations and their links to patient characteristics is becoming increasingly necessary.