Incidence and characteristics of Epidermal Growth Factor Receptor (EGFR) mutation in non-small-cell lung cancer (Adenocarcinoma histology): A report of 106 patients from Kolkata.

Context: Regional epidemiological data regarding the epidermal growth factor receptor (EGFR) mutation status in non-small-cell lung cancers (NSCLC) is an unmet need from the eastern part of India.
Aims: To report the incidence of EGFR mutation and its correlation with the phenotypical characteristics, in NSCLC patients from Kolkata.
Subjects and Methods: NSCLC patients, with adenocarcinoma histology, whose tissues had been tested for EGFR mutational status between March 2014 and February 2017, were considered for this study. The testing methods used were Real-time-based amplification refractory mutation system, polymerase chain reaction (ARMS PCR), PCR and gene sequencing, and cell-free DNA (CTDNA). Clinical characteristics and treatment details were collected from the patient's medical records in a de-identified manner.
Statistical Analysis Used: Data were analyzed using simple descriptive statistical methods.
Results: Between March 2014 and February 2017, 108 samples were tested and two were deemed inadequate for reporting. Of the remaining 106 patients, 65 (61.3%) were males, and 41 (38.6%) were females. Median age was 56 years (42-72), 59 years for males and 52 years for females. 73.6% were nonsmokers. 87.7% tests were done using the real-time ARMS-PCR; 9.4% underwent PCR and gene sequencing and 2.8% using CT-DNA. Of 106 patients, 35 (33%) patients were found to be EGFR mutation positive. Ratio of male:female was 16 (45.7%):19 (54.3%). Ratio of nonsmoker: smoker was 30 (85.7%):5 (14.3%). 18 patients had exon 19 deletion (51.4%), 15 had L858R exon 21 mutation (42.9%), 1 patient (2.9%) had mutation in S7681 exon 20 along with L858R 21 and one patient (2.9%) had a T790m mutation without any other detectable EGFR mutation.
Conclusions: The incidence of EGFR mutation in NSCLC is 33% from Kolkata and is typically more common in females and nonsmokers.