Detection Of BRAF ^{V600E Gene Mutation In Pleural Effusion Cells Of Primary Pulmonary Adenocarcinoma Of Lung}

Objective To investigate the BRAFV600 E gene mutation in the positive pleural effusion of the patients with NSCLC.Methods Twenty-four patients diagnosed as NSCLC by radiographic and pathologic examination were included in the study, with the positive pleural effusion in which pulmonary adenocarcinoma cells were detected. Cell blocks were made by centrifugal sediment of the positive pleural effusion. Amoy Dx® FFPE DNA Kit(Spin Column) was used to separate DNA in cell blocks, then PCR was used to amplify DNA by the method of ARMS to detect gene mutations of BRAFV600 E. Furthermore, we detected BRAF protein expressions in the positive pleural effusion of all 24 patients by the method of Maxvisiontm immunohistochemical staining.Results Test success rate was 100%. BRAFV600 E gene mutation was checked out in two cases(one male and one female) and mutation detection rate was 8%. Among all of 24 patients, BRAF protein expression was positive in 16 cases, and negative in eight cases.The positive expression rate was 67%. BRAF protein expression of the female patient with the gene mutation was negative, while BRAF protein expression of the male patient with the gene mutation was positive. Among other 22 patients without BRAFV600 Egene mutation, BRAF protein expression was negative in seven cases, and was positive in 15 cases. Compared the number of the cases with negative BRAF protein expression by immunohistochemical method with the number of the cases with negative BRAFV600 E gene mutation by ARMS method, the coincidence rate was only 32%.Conclusions It has certain feasibility that the positive pleural effusion of the patients with NSCLC detect BRAFV600 Egene mutation. It has the potential to replace the detection method using the tumor tissue for guiding the targeted drugs therapy in terminal NSCLC patients, and provides a possible method to test other genes using the positive pleural effusion. In addition, The study indicated that the result of detecting BRAFV600 E gene mutation can’t be replaced by BRAF protein expression.