Epidermal growth factor receptor variants in patients from Myanmar with lung adenocarcinoma

Abstract

Abstract Background Epidermal growth factor receptor (EGFR) sequence variants in patients from Myanmar have not yet been reported. Objectives To describe the molecular epidemiology of EGFR variants in patients from Myanmar with lung adenocarcinoma. Methods Histological diagnosis and categorization of biopsies collected from 66 patients (28–78 years) with lung cancer was conducted using a panel of antibodies including those to: TTF1, P40, synaptophysin, CK7, and napsin-A. Samples from patients with confirmed adenocarcinoma were tested for EGFR variants using a cobas EGFR Mutation Test kit and cobas z 480 System (Roche). We conducted a univariate analysis of categorical factors using a χ2 or Fisher exact test. Results Histological types were adenocarcinoma (61%, 40/66), squamous cell carcinoma (24%, 16/66), neuroendocrine carcinoma (9%, 6/66), undifferentiated carcinoma (2%, 1/66), adenosquamous carcinoma (2%, 1/66), small cell anaplastic carcinoma (2%, 1/66), and pleomorphic sarcoma (2%, 1/66). EGFR variants were detected in 15 of 40 (38%) cases of adenocarcinoma. Among them, 6 patients (40%) had an exon 19 deletion, another 6 (40%) had exon 21 substitutions, 1 (7%) had exon 20 insertion S768I, and 2 (13%) had compound variations (1 of exon 21 L858R and exon 18 G719X, and 1 of exon 20 S768I and exon 18 G719X). Although limited by small sample size, no significant association was found between the variants and factors including family cancer history, age group, sex, ethnicity, or occupation. However, there was a strong significant association between never-smokers and EGFR variants (P = 0.008). Conclusion Knowledge of EGFR variants in patients from Myanmar is encouraging for their effective cancer treatment.