ROS1 and lung carcinoma: While our study with a limited sample size of RET and ROS1 rearranged lung cancer showed no significant differences between RET or ROS1 rearranged and non-rearranged tumors regarding clinicopathological characteristics, previous investigations have reported a higher incidence of RET and ROS1 rearrangements in younger age group and never smokers [60, 61] as well as a significant association of RET rearranged NSCLC with small primary tumor size and lymph node involvement [60, 62].