[Comparison of EGFR mutation status in paired pre- and post-chemotherapy serum for advanced pulmonary adenocarcinoma].

Background And Objective: Non-small cell lung cancer (NSCLC) with mutations in the epidermal growth factor receptor (EGFR) is a distinct subgroup of NSCLC, which is particularly responsive to EGFR tyrosine kinase inhibitors (TKIs). The aim of this study is to detect EGFR mutations in paired serum of pre- and post-chemotherapy from advanced pulmonary adenocarcinoma patients to evaluate impact of chemotherapy on EGFR mutation status.

Methods: Magnetic beads were used for DNA extraction from paired serum of pre- and post-chemotherapy of 33 advanced pulmonary adenocarcinoma patients. The EGFR exon 19 and 21 were amplified by mutant-enriched nested PCR and analyzed by direct sequencing.

Results: EGFR mutations were detected in 39.4% (13/33) and 54.5% (18/33) serum samples of pre- and postchemotherapy, respectively. The EGFR mutation status was consistent in 54.5% (18/33) patients. Among 15 discordant cases, 10 changed from pre-chemo wild-type to post-chemo mutant-type status, while 5 from pre-chemo mutant-type to post-chemo wild-type status.

Conclusions: Chemotherapy may have influence on serum EGFR mutation status in advanced adenocarcinoma patients.