Although the best reported data for patients with lung adenocarcinoma were obtained with an EGFR-mutation test that uses ddPCR, which resulted in a 92% sensitivity and 100% specificity, lower or more varied levels of sensitivity (29.0–100.0%) and specificity (50.0–100.0%) have also been observed in EGFR T790M testing [22, 26, 30, 32, 33]. This evidence concerns the gene EGFR and lung adenocarcinoma.