Metastatic germ cell tumor showing a durable response to the anti-PD-1 antibody toripalimab.

Rescue treatment for recurrent and metastatic germ cell tumors is limited. Immune checkpoint inhibitors have shown certain efficacy and safety in the treatment of a variety of tumors. Here we describe a case of metastatic germ cell tumor in which 30% of cells were positive for PD-L1. This tumor achieved a durable response to toripalimab, a monoclonal anti-PD-1 antibody. Follow-up for 36 months post-treatment confirmed no disease progression. We not only report the first use of toripalimab for the treatment of a metastatic germ cell tumor but also describe a patient with the longest sustained remission with an anti-PD-1 antibody to date.