<h4>Objectives</h4>Progressive arthropathy was anecdotally described in patients exposed to crizotinib, a receptor tyrosine kinases inhibitor (TKI) used to treat anaplastic lymphoma kinase (ALK) or ROS Proto-Oncogene 1 (ROS1) positive non-small cell lung cancer (NSCLC). The gene discussed is ALK; the disease is non-small cell lung carcinoma.