KIF5B and non-small cell lung carcinoma: The RET fusion occurs in 1–2% of NSCLC, particularly in younger, non‐smoking patients with adenocarcinoma histology [5], and they appear to be associated with a high risk of metastasis to the brain [6]. In contrast, KIF5B-RET and CCDC6-RET fusion genes have been identified in 70 to 90% and 10 to 25% of tumors, respectively [7].