Anaplastic lymphoma kinase inhibitor-associated myositis.

Anaplastic lymphoma kinase (ALK) inhibitors have been used in patients with non-small cell lung cancer (NSCLC) harboring EML4 - ALK fusion gene.1 Severe skeletal muscle adverse events of ALK inhibitors, such as muscle weakness, have seldom been reported.2,3 Herein, we describe a patient who showed a severe skeletal muscle deficit after the administration of the ALK inhibitor, alectinib, and was successfully treated by corticosteroids without withdrawal from the cancer therapy. The authors thank Petra Matylewski and Silvia Stefaniak in the Department of Neuropathology, Charite–Universitatsmedizin for their excellent technical assistance.