Recurrent thrombosis followed by Lazarus response in ROS1 rearranged NSCLC treated with crizotinib: a case report

Introduction: Patients with cancer have higher risk of thrombosis compared to the general population and particularly lung adenocarcinoma is considered at high risk for venous thromboembolism. Some targetable oncogenic drivers are supposed to further increase this risk. Case description: A 35-year-old man who had developed a recurrent venous thromboembolism and pulmonary embolism (PE) was diagnosed with ROS1 rearranged non-small cell lung cancer (NSCLC). While molecular examinations were ongoing, he developed progressive respiratory failure. For PE and thrombosis worsening with detection of right heart thrombus, he underwent therapy with unfractionated heparin. Despite initial good radiologic results, only with the start of crizotinib did the patient’s clinical condition significantly improve to configure a Lazarus response. Conclusions: Cancer diagnosis should always be considered in patients with unprovoked thrombosis and, if NSCLC is diagnosed, genetic alterations should be always sought after. A possible relation between venous thromboembolism and oncogenic drivers, particularly for ALK translocations, has been hypothesized. Similarly to ALK-positive NSCLC, ROS1 rearranged disease has been associated with an increased thromboembolic risk. Further studies are needed to better evaluate this relation and to evaluate the potential benefit of a prophylactic anticoagulating treatment in this subset of patients.