Although RET fusions have not previously been described in lung cancer, a recent study identified in-frame fusion transcripts of KIF5B (the kinesin family 5B gene) and the RET oncogene, which are present in 1-2% of lung adenocarcinomas (LADCs) from people from Japan and the United States, using whole-transcriptome sequencing [21]. Here, KIF5B is linked to lung adenocarcinoma.