Unusual presentation of ROS1 rearranged metastatic non-small cell lung cancer

The spectrum of clinical and radiographic presentations of lung adenocarcinoma is increasingly broad, including in the metastatic setting. Here, we report on a patient who initially presented with a mild chronic cough that remained stable over a decade, with serial CT scans showing gradual worsening of multifocal areas of consolidation and ground-glass opacities of the bilateral lungs. The patient was ultimately diagnosed with ROS1 rearranged lung adenocarcinoma and achieved a dramatic response with entrectinib. This case highlights the variable presentation of non-small cell lung cancer (NSCLC) and the importance of comprehensive molecular testing for newly diagnosed metastatic NSCLC.