PB2308: NIVOLUMAB-BASED THERAPY OF RELAPSED OR REFRACTORY PRIMARY LARGE B-CELL LYMPHOMA OF IMMUNE-PRIVILEGED SITES AND DLBCL WITH SECONDARY CNS INVOLVEMENT oleh Andrey Gavrilenko, Vladislav Markelov, Nikita Volkov, Daniil Shmidt, Yaroslav Skiba, Elena Kondakova, Lepik Kirill, Liudmila Fedorova, Marina Popova, Natalya Mikhaylova, Alexander Kulagin