Abstract
Objective In this study, we sought to elucidate the relationship between demographic and clinical factors and epidermal growth factor receptor tyrosine kinase (EGFR-TK) positivity in patients with advanced-stage lung cancer at a tertiary care center in Pakistan. Methods This analytical cross-sectional study was conducted from February 2020 to July 2023 at Shaikh Zayed Hospital, Lahore, Pakistan, in collaboration with the Centre of Excellence in Molecular Biology (CEMB), University of the Punjab. The study included 70 consecutive patients with advanced-stage lung cancer, and aimed to identify common EGFR mutations (Exon 19 deletion and Exon 21 L858R mutation), determine their frequency, and correlate EGFR-TK mutation positivity with clinical and non-clinical factors. Tissue acquisition and processing involved bronchoscopy, pleuroscopy, or percutaneous ultrasound-guided lung mass biopsy, followed by molecular analysis using polymerase chain reaction (PCR) extraction, amplification, and sequencing. The study employed convenient sampling and included adults aged over 18 years with histologically confirmed lung cancer. Results We enrolled 70 lung cancer patients, with a mean age of 60.87 years, and a male-to-female ratio of 1.4:1. The majority (61.4%) had adenocarcinoma, and 34.3% harbored a mutant EGFR-TK. EGFR mutations were more common in adenocarcinoma (91.7%) and associated with female non-smokers. Binary logistic regression analysis revealed that age <50 years and adenocarcinoma type were significant predictors of EGFR mutations. We found no significant associations with gender, smoking status, or other variables. These findings have implications for personalized treatment approaches in lung cancer patients. Conclusions Our study reveals a high frequency of occult EGFR mutations (Exon 19 deletion and Exon 21 L858R mutation) in non-small cell lung cancer (NSCLC) patients, particularly among male smokers and female non-smokers. These findings emphasize the importance of routine EGFR mutation testing to identify patients who may benefit from targeted therapies, ultimately improving treatment outcomes.