ROS1 and lung adenocarcinoma: Tanaka and coworkers confirmed these findings in a group of 81 Japanese young lung adenocarcinomas, showing in these patients a very high frequency of ALK translocations (41%) and EGFR mutations (30%), but a low frequency of KRAS mutations (2%); furthermore, about 6% of these patients displayed RET or ROS1 translocations [24].