Immunotherapy of Nivolumab with Dendritic Cell Vaccination Is Effective against Intractable Recurrent Primary Central Nervous System Lymphoma: A Case Report.

We report effective treatment with nivolumab of a patient with recurrent primary central nervous system lymphoma (PCNSL) after multiple therapies. A 41-year-old woman with a right parietal PCNSL underwent treatment with high-dose methotrexate and radiotherapy. After recurrence in the left frontal lobe, the patient received several chemotherapies, including methotrexate and rituximab, and underwent surgery. The tumor was refractory to these treatments, and the patient then underwent intensity-modulated radiotherapy (IMRT). Multiple small, new recurrent tumors appeared in the right frontal lobe and the left frontoparietal region 2 months after IMRT. The patient received nivolumab 3 mg/kg with dendritic cell vaccination. Complete remission of the tumors was achieved after six cycles of nivolumab, and remission was maintained for 10 months after the initiation of nivolumab. Nivolumab could be a novel treatment for intractable recurrent PCNSL in the future.