Evaluation of different platform detection of cfDNA tumor mutation in patients with NSCLC / 中华检验医学杂志

ABSTRACT

Objective:To verify the performance of the next-generation sequencing (NGS) platform and evaluate the application of NGS, droplet digital PCR (ddPCR) and super amplification refractory mutation system (super-ARMS) in the detection of circulating free DNA (cfDNA) mutations in patients with non-small-cell lung cancer (NSCLC).Methods:A total of 75 patients with NSCLC in the respiratory department of Zhongshan Hospital Affiliated to Fudan University were enrolled. The standards, cfDNA from 25 patients with newly diagnosed and untreated NSCLC, and self-made mixed samples mixed with hemoglobin (1 000 mg /dl), bilirubin (500 mg/l), fat emulsion (2%), enterococcus gDNA and Escherichia coli gDNA were used to verify the blank limit, analytical sensitivity, precision, accuracy and specificity of NGS platform. The cfDNA mutations of 75 NSCLC patients were detected by ddPCR and NGS, and the mutation positive rates of the two platforms were compared. The linear relationship between the two platforms was compared by Pearson correlation test. 12 patients were selected by simple random sampling for the detection of plasma super-ARMS platform. The performance of three platforms in the detection of plasma cfDNA mutation in patients with NSCLC was compared.Results:The blank limit of NGS platform was set to 0.00%, the analytical sensitivity was 0.2%, the intra-assay precision and inter-assay precision were 100%. The test results were not affected by endogenous hemoglobin, bilirubin or fat emulsion in plasma or exogenous DNA interference, and the analysis specificity was good. The mutation positive rates of plasma cfDNA in 75 NSCLC patients detected by ddPCR and NGS were 61.33% and 60.00%, respectively. The complete coincidence rate was 89.33%, which suggests there was a positive correlation between the mutation abundance of NGS and ddPCR ( r=0.984, P=0.001). Among the plasma of 12 NSCLC patients, the results of NGS, ddPCR and super-ARMS were completely consistent in 7 cases, including 2 wild-types and 5 mutants. Conclusion:The NGS platform was verified to be useful for cfDNA mutation detection in patients with NSCLC. The ddPCR, NGS and super-ARMS have their own advantages in detecting cfDNA mutations in patients with NSCLC.