8054 Background: In the treatment of advanced NSCLC, EGFR mutation status is one of the most predictive factors for the efficacy of EGFR tyrosine kinase inhibitors, and the evaluation of EGFR mutation status using the PPFE has been widely used for this analysis throughout the world. However, whether BWC can be used as an alternative for PPFE in the analysis of EGFR mutations is unknown. The largest study evaluating these 2 methods included only around 20 samples. Therefore, in the current study, we compared the freeze stock solution of BWC with PPFE for the determination of EGFR mutation status in a large sample set. Methods: In diagnostic BFS examinations, after curetting or brushing and biopsy to target lesions, subsequent bronchial washing by saline was performed. Thereafter, the saline fluid in which the forceps were washed and the bronchial washing fluid were mixed in a sterilized tube and were immediately frozen in a -20°C freezer. EGFR mutation testing for both BWC and PPFE was performed using high-sensitivity PCR (BML, PCR-Invader). Results: A total of 440 BFS examinations were performed from Aug 2010 to Nov 2011 in our hospital. The BWCs of 268 suspected cases of lung cancer were successfully obtained. Of these, 51 cases that were pathologically confirmed as adenocarcinoma based on both BWC and PPFE were analyzed in this study. EGFR mutations were identified in 25 cases, while the remaining 26 cases had wild-type EGFR. In 49 of 51 cases, the results of EGFR mutation status were the same for BWC and PPFE, and the concordance rate was 96%. In one case, an exon-18 mutation was detected only by BWC. In another case an exon-21 mutation was detected only by PPFE. In 24 of 25 cases of EGFR mutation, the mutation site was the same in both samples. The kappa coefficient was 0.92. Conclusions: This is the largest genetic study to date demonstrating a head-to-head comparison of BWC and PPFE for the evaluation of EGFR mutations. Both methods showed high reliability and concordance using high-sensitivity PCR. BWC is considered a simple, rapid method and represents an effective alternative for PPFE in EGFR mutation testing.
O-023THE CHANGES IN CIRCULATING TUMOUR CELLS COUNTS IN PULMONARY VENOUS BLOOD AFTER SURGICAL MANIPULATION IS A PREDICTIVE MARKER OF POSTOPERATIVE DISTANT METASTASIS IN PRIMARY LUNG CANCER PATIENTS
