Immunotherapy of Nivolumab with Dendritic Cell Vaccination Is Effective against Intractable Recurrent Primary Central Nervous System Lymphoma: A Case Report
Primary central nervous system lymphoma (PCNSL) is a brain tumor sensitive to chemotherapy and radiotherapy. Methotrexate (MtX)-based chemotherapy is a first-line therapy for PcNsL. high-dose methotrexate (hD-MtX) followed
by radiotherapy has high response rates. However, PcNsL always relapses after chemo-radiotherapy, and no treatment
has had convincing beneficial effects on recurrent PcNsL. Median survival after recurrence is 14 months, even with
salvage therapy. Recurrent PcNsL is one of the intractable brain tumors refractory to any treatment and still has a poor
prognosis.
Patient
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.
The multiple small, new tumors were completely remitted after six cycles of nivolumab. After four more cycles, magnetic resonance images taken 7 months after iMrt showed a contrast-enhanced lesion adjacent to the left frontal horn of the lateral ventricle, and the patient showed a personality change.
Results
Complete remission of the tumors was achieved after six cycles of nivolumab, and remission was maintained for 10
months after the initiation of nivolumab.
Conclusion
Immunotherapy of nivolumab with dendritic cell vaccination is expected to be a novel treatment for intractable recurrent PCNSL. Recurrent tumors were completely remitted after nivolumab treatment, although PD-L1 was expressed not on tumor cells but on tumor-associated macrophages in the patient.
Dendritic cell vaccination theoretically reinforces effects of nivolumab on tumors and the synergistic effect of nivolumab and dendritic cell vaccination should also be elucidated.
