Additional coexisting mutations and the proportion of EGFR mutations can affect PFS (21), and immunohistochemical analyses of tumor tissue from NSCLC patients treated with first-line EGFR-TKIs have shown that co-occurring PTEN loss and IGFR overexpression correlated with poorer PFS and OS (22). The gene discussed is EGFR; the disease is non-small cell lung carcinoma.