The Frequency of Epidermal Growth Factor Receptor (EGFR) mutations in Iraqi patients with Non-Small Cell Lung Cancer (NSCLC)

OBJECTIVE: Non-Small Cell Lung Cancer (NSCLC) Carcinogenesis could be caused by numerous genetic mutations, one of the most common is the mutation in the Epidermal Growth Factor Receptor (EGFR) which was used in the advanced stages of the disease as a therapeutic goal. This study aims to estimate the frequency of Epidermal Growth Factor Receptor mutations in Iraqi patients with Non-Small Cell Lung Cancer. METHODS: One hundred thirty-eight patients confirmed with NSCLC have participated in this study, patients were sent for EGFR testing by different oncology centers in Iraq. Data and samples were collected. The Mutation was detected using COBAS(®) DNA Sample Preparation Kit that designed to detect the following mutations: Exon 19: deletions and complex mutations; Exon 21: L861Q and L858R; Exon 18 mutation: G719X (G719A, G719C, and G719S); Exon 20: S768I, T790M, and insertions, this kit utilizes the technology of the real time Polymerase Chain Reaction. RESULTS: This study was included 79 males and 59 females, with a mean age of 60.1±12.4 years. A positive EGFR mutations were found in 38 (27.53%) of samples. Exon 19 deletions (25/38, 65.8%) and substitution L858R in exon 21 10/38 (26.3%) were the most common mutations. Multiple mutations (Exon 20 and 19 combined together) were founded in 2/38 (5.3%), and 1/38 (2.6%) ALK mutation. Non-significant differences among age groups and gender in the incidence of mutations were found. CONCLUSION: The current study represents the first epidemiological study in Iraq to find EGFR mutations frequency among NSCLC patients that reveals the incidence rate of 27.53%, which is between the higher prevalence rate in Asian populations and lower rates in western countries. These results explain the genetic differences of NSCLC in the world due to ethnic differences of the population, more studies are needed in Arab countries to study the EGFR mutations, find the effect of ethnicity and environmental factors for lung cancer, and the subsequent therapy.