RET and non-small cell lung carcinoma: RET fusions have been found in 10–20% of papillary thyroid carcinoma (PTC), ∼1–2% of non-small-cell lung carcinoma (NSCLC), and more recently, in 3% of Spitzoid tumors (Wiesner et al., 2014; Romei et al., 2016; Drilon et al., 2018a; Liang et al., 2018).