P3.02b-054 EGFR Mutation Profile in Newly Diagnosed Lung Adenocarcinoma in Persahabatan Hospital, Jakarta-Indonesia

Abstract

In Indonesia, gefitinib or erlotinib were given for free under National Health System Insurance, for EGFR sensitizing mutaton positive patients. Our previous study showed proportion of common EGFR mutation in Indonesian patients, however, the proportion of uncommon mutation and resistant mutation were not yet known. Here we report the spectrum of EGFR mutation among newly diagnosed-therapy naive adenocarcinoma NSCLC in respiratory referral hospital, Persahabatan Hospital, Jakarta Indonesia. Newly diagnosed-therapy naive lung adenocarcinoma were evaluated for EGFR mutation between September 2015–April 2016. Four exons of EGFR were tested using a combination of PCR High Resolution Melting, fragment sizing, and direct DNA sequencing. One hundred and thirty nine subjects were enrolled from September 2015 to March 2016 in Persahabatan hospital, with distribution 63% were male, and 56 years old (mean). Most specimens were obtained using bronchoscopy (31%) followed by TTNA (30%) and pleural effusion (17%). Overall EGFR mutation rate was 61.9%, and more frequent in female (72% of female subjects has EGFR mutation whereas only 55% of male subjects has positive results). Of the positive EGFR mutation subjects; 1% has Exon 18 G17S; 5.8 % Exon 18 G719S; 17.5% Exon 19 In/Del; 43% Exon 21 L858R; and 21% Exon 21 L861Q. The incidence of primary resistant Exon 20 T790M mutation was 11.6% and more frequent in female. EGFR mutation is common in Indonesian population of newly diagnosed naive adecarcinoma NSCLC. Baseline rate of T790M was not rare when detected using standard direct DNA sequencing. Further study is needed to elaborate proportion of primary resistant and biological mechanism in Indonesian lung cancer patients.