Abstract
BACKGROUND: Epidermal growth factor receptor (EGFR) mutation and c-ros oncogene 1 (ROS1) rearrangement are key genetic alterations and predictive tumor markers for non-small cell lung cancer (NSCLC) and are typically considered to be mutually exclusive. EGFR/ROS1 co-mutation is a rare event, and the standard treatment approach for such cases is still equivocal. CASE SUMMARY: Herein, we report the case of a 64-year-old woman diagnosed with lung adenocarcinoma, with concomitant EGFR L858R mutation and ROS1 rearrangement. The patient received two cycles of chemotherapy after surgery, but the disease progressed. Following 1-month treatment with gefitinib, the disease progressed again. However, after switching to crizotinib, the lesion became stable. Currently, crizotinib has been administered for over 53 months with a remarkable treatment effect. CONCLUSION: The efficacy of EGFR tyrosine kinase inhibitors and crizotinib was vastly different in this NSCLC patient with EGFR/ROS1 co-mutation. This report will aid future treatment of such patients.