EGFR-TKI Sensitizing Mutation Rate in Adenocarcinoma of Lung

Abstract

Objective: To assess EGFR-TKI sensitizing mutation rate in patients having lung adenocarcinoma and its association with smoking status. Study Design: Cross-sectional study. Place and Duration of Study: Department of Medical Oncology, Jinnah Postgraduate Medical Center, Karachi Pakistan from Apr to Dec 2019. Methodology: One eighty-seven patients aged 20-75 years, of either gender presented with confirmed diagnosis of adenocarcinoma of lung were included in the study. The data regarding characteristics of patients such as gender, age, smoking status, ethnicity and religion were recorded on pre-designed proforma. The examination of EGFR mutation in plasma and tissue specimens was done by the Real-Time polymerase chain reaction assays. SPSS version 23 was used to analyze data. Results: Out of 187, 65(34.8%) patients presented with EGFR TKI-sensitizing mutation and among them 48(73.8%) patients had exon 19 deletion and 17(26.2%) patients had exon 21 L858R point mutation. In patients with positive EGFR, 90.8% were never smokers and 9.2% were smokers or ever smokers. The statistically significant relationship was found between EGFR mutation and smoking status (p=0.001). Conclusion: This study showed EGFR-TKI mutation frequency as 34.8% which in contrast to western studies where EGFR mutation is less frequent. Further, never smokers are at greater risk of EGFR mutation.