BackgroundEpidermal growth factor receptor (EGFR) represents an important molecular target in the treatment of lung adenocarcinomas; many anti-EGFR therapies are approved as first line and second-line treatment in patients having metastatic lung adenocarcinomas. The occurrence of this mutation varies in terms of race; it is around 10% in Caucasians and can reach 30% in Asians. Its prevalence in our Middle Eastern region is not well known. MethodsPatients diagnosed with non-squamous non-small cell lung carcinomas between March 2013 and March 2015 were included. This study was conducted at Hôtel-Dieu de France University Hospital, a tertiary medical center in Lebanon. EFGR mutations were analyzed using real time PCR technique on the Rotor-Gene Q using Scorpions and ARMS technologies. The following data was collected: the patients’ characteristics (age, gender, smoking status, stage), the samples’ characteristics (histology subtype, TTF-1 and Napsin A immunostainings, the site and the adequacy and the type of the sample), and the mutational EGFR status (presence and type of mutation). These variables were analyzed using SPSS 20. Results201 patients were included. The mean age was 65.2 years [31–87]; 40.2% were females. 78.1% of the included patients were smokers or ex-smokers. 12.9% of patients had a localized disease, 17.4% a locally advanced disease and 69.7% a metastatic disease. Adenocarcinoma was the main histologic subtype found in 90.5% of patients, followed by large cell carcinoma (3.5%), adenosquamous carcinoma (3.0%) and non-small cell carcinoma not otherwise specified (3.0%). 11.9% of patients had an EGFR mutation: 48% of them presented a deletion on exon 19, 40.0% a L858R mutation on exon 21, 4.0% a G719X mutation in exon 18, 4.0% an insertion in exon 20, and 4% a T790M mutation in exon 20. The presence of an EGFR mutation was significantly associated with the female gender (two-third) (p<0.05) and the non-smoking status (two-third) (p<0.05). ConclusionsThe prevalence of EGFR mutation (11.9%) detected in our Lebanese population is similar to that observed in the Caucasian population. This mutation is also significantly more frequent in females and non-smokers.