ROS1 and neoplasm: Most PPLELC patients lack mutations in common tumor promoting genes such as EGFR and ALK. [9–11] In this case, no mutations were found in the classic driver genes such as EGFR, ALK, K-RAS, and ROS1. Recent exciting basic and clinic studies demonstrated that immunotherapy and immunotherapy improve the immune function of the body, increase the activity of immune cells, and reduce the suppression of immune cells by the tumor microenvironment.