RESUMO
Objectives To estimate the proportion of positive epidermal growth factor receptor (EGFR) mutations among patients diagnosed with non-small cell lung carcinoma (NSCLC) and T790M at the King Khalid University Hospital (KKUH). Methods A retrospective cohort study that included all patients that were diagnosed with NSCLC from 2009 to 2017 at KKUH. Data obtained from both electronic and paper medical records and the following information were studied: age, gender, smoking, region, subtype of NSCLC, EGFR mutation test result, treatment, T790M mutation test (if required), comorbidities, metastasis. Statistical analysis was performed using the Statistical Package for the Social Sciences (SPSS, version 21.0; SPSS Inc., Chicago, IL, USA). Results Among 71 patients with NSCLC 18 cases were identified for EGFR positive mutation and only one case for T790M. Deletion mutation in exon 19 represented 50% of total cases. Moreover, it showed that it is more frequent in males and non-smokers with 61.1% (11) and 66.7% (12), respectively. Majority of the cases were above the age of 60 years by 61.1% (11). The mutations reported highest in those living in Najd with a 44.4% (8) and all the mutated cases were adenocarcinoma. There was no statistical significance in the association between EGFR mutation and disease variables. Conclusion Ultimately, we found that the frequency of EGFR and T790M mutations among NSCLC patients at KKUH from 2009 to 2017 was 25.4% and 1.4%, respectively. Moreover, this result was conspicuous among non-smokers.