2021 Volume 20 Issue 3 Pages 179-186
A 78-year-old man underwent chemotherapy for non-small-cell lung cancer, resulting in tumor progression. Atezolizumab, a PD-L1 antibody, was started as second-line anti-cancer therapy. After the seventh administration, itchy edematous erythema developed mainly on the trunk. Although topical steroid therapy was applied, edematous erythema developed on both eyelids and dark-red erythema developed on the dorsal hand. Moreover, increased blood myogenic enzyme,muscle weakness with a proximal predominance, and antiTIF1-γ antibody positivity were noted,leading to a diagnosis of dermatomyositis. We discontinued atezolizumab and started systemic steroids, and symptoms went into remission. Later, the cutaneous and muscular symptoms recurred with the progression of lung cancer. The patient passed away from the progression of lung cancer due to the poor effects of docetaxel chemotherapy. In recent years, immune-related adverse events have become more important with the increasing use of immune checkpoint inhibitors. There are few reports of dermatomyositis as an immune-related adverse event, but we suspected our case to be similar. However, it is difficult to exclude paraneoplastic dermatomyositis. Further accumulation of cases is necessary to clarify the pathological mechanisms. Skin Research, 20 : 179-186, 2021
