In addition to the obvious limitations, arising from the retrospective nature of the study, the authors acknowledge that one of the main limitations of this study is the incorporation of the second-generation EGFR TKI afatinib for EGFR-mutated NSCLC in the last years which may have changed the prescription patterns regarding the type of EGFR TKI used. Here, EGFR is linked to non-small cell lung carcinoma.