EGFR and non-small cell lung carcinoma: In our study, we actually attempted to determine the proportion of mutated neoplastic cells that best identifies the subset of patients that benefits most from TKIs therapy: patients with a NSCLC harboring EGFR mutations in more than 56% of neoplastic cells have a median OS trice longer in comparison to that of patients harboring tumors with a lower percentage of mutated neoplastic cells.