The ROS1 fusion-positive NSCLC patients who received pemetrexed-based chemotherapy had a relatively better ORR or DCR than those treated with non-pemetrexed-based chemotherapy; however, the difference did not reach the statistical significance (ORR, 53.6% vs. 36.8%, P = 0.259; DCR, 82.1% vs. 63.2%, P = 0.143). This evidence concerns the gene ROS1 and non-small cell lung carcinoma.