A 57-year-old man presented with swelling and pain in the lower limbs, inability to walk and increasing dyspnea for 2 days. Because of refractory stage IV non-small-cell lung cancer, pembrolizumab was started 21 days before presentation. Since then, he experienced general discomfort, fatigue and bilateral weakness in the legs with exercise limitation. A diagnosis of pembrolizumab-induced grade III myositis was made based on muscle biopsy. Pembrolizumab is a humanized monoclonal antibody against PD-1. It has been approved for the treatment of metastatic melanoma and refractory non-small-cell lung cancer with increased expression of PD-L1 on the cell surface of tumor cells. With such a humanized monoclonal antibody, fewer adverse events are expected than with systemic chemotherapy. However, 13% of patients develop autoimmune side effects which can be severe (grade III, IV or V) in 5-10%. We discuss a case of pembrolizumab-induced myositis, with a brief overview of the literature. Only three cases of pembrolizumab-induced myositis have been reported in literature.
Keyphrases
- monoclonal antibody
- high glucose
- advanced non small cell lung cancer
- diabetic rats
- drug induced
- systematic review
- case report
- endothelial cells
- small cell lung cancer
- poor prognosis
- multiple sclerosis
- cell surface
- spinal cord injury
- ejection fraction
- physical activity
- rheumatoid arthritis
- newly diagnosed
- early onset
- epidermal growth factor receptor
- pain management
- locally advanced
- patient reported outcomes
- radiation therapy
- neuropathic pain
- postoperative pain