Objectives: Pathological classification of lung cancer is based on the expression of immunohistochemical markers, and evaluating the characteristics of EGFR gene mutations of lung cancers. Subjects and methods: The cross-sectional, descriptive, retrospective and prospective study of 193 patients, 150 males and 43 females, who were diagnosed with lung cancers on lung tumor surgical specimens, bronchoscopy biopsies, transthoracic biopsies, and the cell blocks obtained by pleural fluid at 103 Military Hospital, from April 2014 to June 2018. | Journal of military pharmaco-medicine no1-2019 CHARACTERISTICS OF THE PATHOLOGICAL, IMMUNOHISTOCHEMICAL FINDINGS AND EGFR GENE MUTATION ON BIOPSIES IN 193 LUNG CANCER PATIENTS Dinh Tien Truong1; Tran Ngoc Dung1; Nguyen Khac Tuyen1 Nguyen Manh Hung1; Tran Viet Tien1 SUMMARY Objectives: Pathological classification of lung cancer is based on the expression of immunohistochemical markers, and evaluating the characteristics of EGFR gene mutations of lung cancers. Subjects and methods: The cross-sectional, descriptive, retrospective and prospective study of 193 patients, 150 males and 43 females, who were diagnosed with lung cancers on lung tumor surgical specimens, bronchoscopy biopsies, transthoracic biopsies, and the cell blocks obtained by pleural fluid at 103 Military Hospital, from April 2014 to June 2018. The new WHO pathological classification of lung cancer (2015) was applied, as well as the EGFR gene mutation was analyzed. Results: Patients with mean age of ± , male/female ratio: . 4 pathological types were determined: adenocarcinoma (), squamous cell carcinoma (), small cell carcinoma () and carcinoid tumor (). The panel of TTF-1, p63, CK5/6 was valuable in the differential diagnosis of adenocarcinoma and squamous cell carcinoma with sensitivity over 70%. The panel of synaptophysin, chromogranin, NSE was valuable in the diagnosis of small cell carcinoma, carcinoid tumor with high sensitivity. of these cases had an EGFR mutation which mainly appeared on adenocarcinoma th (), and 19 deletions (). Conclusion: Immunohistochemistry is valuable to identify the pathological classification of lung cancers on biopsies. EGFR gene mutations are mainly th found on adenocarcinoma, and on 19 exon. * Keywords: Lung cancer; EGFR mutations; Pathological diagnosis; Immunohistochemical markers. INTRODUCTION Lung cancers are the common malignant tumor and have a high mortality rate in both sex. According to Globocan (2012),
