Study of epidermal growth factor receptor gene mutation in liquid biopsy of cerebrospinal fluid supernatant from patients with lung adenocarcinoma / 中华老年医学杂志

ABSTRACT

Objective To study the detection protocol of epidermal growth factor receptor (EGFR)gene mutations in cerebrospinal fluid(CSF)specimens of lung adenocarcinoma by establishing a liquid biopsy technique,and to analyze clinical value of the detection findings for clinical therapy.Methods In the retrospective study,a total of 26 CSF specimens from lung adenocarcinoma patients who harbored EGFR gene mutations(L858R and EGFR exon 19 deletion)were collected.The included patients were treated with first-generation EGFR TKIs,and had brain metastasis detected by imaging examinations.Five CSF specimens from non-tumor patients confirmed by clinical findings and cytological and pathological diagnosis were collected during the same period.EGFR gene mutations in cell-free CSF supernatant fluid were detected by using the protocol recommended in this study.Results EGFR mutations were detected in 21/26 (80.8％)of cell-free supernatants from CSF specimens of lung adenocarcinoma patients,including 13 cases(61.9％)with EGFR L858R mutations and 8 cases(38.1％)with EGFR exon 19 deletion.No T790M mutation was detected in cell-free supernatants from all CSF specimens.No EGFR mutation was detected in cell-free supernatants from all CSF specimens from non-tumor patients.Conclusions Our study-established protocol could be used to detect EGFR mutations in cell-free supernatants from CSF specimens with high sensitivity and specificity.Perhaps due to the characteristics of first-generation EGFR TKIs,the detection rate of T790M mutation is low.The detection of T790M mutation in cell-free supernatants from CSF specimen may have a limited clinical value for choice of 3rd generation EGFR TKIs.