Of the 50 EGFR mutation positive plasma samples, 25 (50.0%) harbored single E19Dels, 21 (42.0%) single L858R mutation, 1 (2.0%) E20-ins mutation and 3 (6.0%) double mutations (2 E19Del + T790M, 1 L858R + T790M), suggesting a similar mutation profiling to the tumor tissues. Here, EGFR is linked to neoplasm.