Stage IV gastric cancer complicated by paraneoplastic dermatomyositis during nivolumab treatment

What happened, in summary

A 71-year-old Japanese man was diagnosed in April 2017 with Stage IV gastric cancer and liver metastases. He began treatment with 4 cycles of cisplatin plus tegafur, gimeracil and oteracil, followed by 4 cycles of paclitaxel plus ramucirumab. The liver metastases initially shrank, but by December 2017 both the stomach tumor and metastatic disease were progressing.

Nivolumab was started as third-line treatment in January 2018. Within 2 weeks he developed worsening fatigue, difficulty swallowing, muscle pain, fever, facial swelling and characteristic skin changes. Nivolumab was stopped. Further assessment showed severe muscle weakness and findings consistent with dermatomyositis, including a high anti-TIF1-gamma antibody level. Skin changes had actually begun before nivolumab, supporting a diagnosis of paraneoplastic dermatomyositis rather than a purely drug-induced reaction.

Steroids, intravenous immunoglobulin and later tacrolimus improved his muscle enzymes and mobility, and he was again able to walk. His swallowing difficulty persisted, however, and gastric-cancer treatment could not continue during this period. His condition then deteriorated rapidly. He died from worsening gastric cancer 142 days after the first nivolumab dose, roughly 14 months after diagnosis. Autopsy showed extensive spread involving the liver, lung and abdominal cavity.