Idiopathic thrombocytopenic purpura induced by nivolumab in a metastatic melanoma patient with elevated PD-1 expression on B cells

Nivolumab has shown promising early results in patients with advanced malignancies, including melanoma and lung cancer, with generally manageable side effects. On the other hand, recent studies showed that the immune activation caused by PD-1 blockade might promote severe autoimmune toxicity. Herein, we report a case of idiopathic thrombocytopenic purpura during nivolumab therapy.