RET and non-small cell lung carcinoma: For NSCLC patients, molecular testing panels are offered based on clinical context and may include EGFR mutation analysis by real-time PCR, ALK and PD-L1 testing by immunohistochemistry, or testing for EGFR (exons 18–21) and ALK, ROS1, RET, NTRK1/2/3 fusions by next-generation sequencing.