A case series of lengthy progression-free survival with pemetrexed-containing therapy in metastatic non--small-cell lung cancer patients harboring ROS1 gene rearrangements.

Clinical Practice Points Tumors with c-ros oncogene 1 (ROS1) translocations are a newly discovered molecular subset of non esmall-cell lung cancer (NSCLC). Like anaplastic lymphoma receptor tyrosine kinase (ALK)-rearranged NSCLC, early phase clinical trials show a high response rate to crizotinib in these patients. Some retrospective studies suggest patients with ALKþ tumors have a longer progression-free survival (PFS) to pemetrexed compared with other chemotherapeutics—though this is controversial. Little is known about whether patients with ROS1-rearranged tumors preferentially respond to specific chemotherapy drugs. This small, retrospective case series suggests that some NSCLC patients whose tumors harbor the ROS1 gene rearrangements might have a lengthy PFS using pemetrexed-containing therapy. In clinical practice, oncologists might want to consider pemetrexed-containing regimens when chemotherapy is indicated.