EGFR and neoplasm: The AFs of sensitizing EGFR mutations measured by ddPCR and NGS at baseline were weakly to moderately well-correlated with baseline tumor volume (Figure 2A,B; Spearman ρ = 0.36 with p = 0.074 for ddPCR and Spearman ρ = 0.45 with p = 0.026 for NGS).