ALK and non-small cell lung carcinoma: Finally, while our model incorporates easily accessible predictors, it is important to recognise that the specificity of the prognostic model could be improved by including NSCLC-related immunohistochemical markers or other relevant genetic mutations, such as programmed death-ligand 1, cytotoxic T-lymphocyte–associated antigen 4, ALK rearrangement, and ROS1 rearrangement (Ahmadzada et al., 2018).