Nivolumab 40 mg in Combination With Chemo-Immunotherapy for Newly Diagnosed Primary Mediastinal B-Cell Lymphoma

This compares the effects of nivolumab at a fixed dose of 40 mg with chemo-immunotherapy versus chemo-immunotherapy alone in treating patients with newly diagnosed primary mediastinal B-cell lymphoma (PMBCL). Immunotherapy with monoclonal antibodies, such as nivolumab, may help the body's immune system attack the cancer, and may interfere with the ability of cancer cells to grow and spread. Treatment for PMBCL involves chemotherapy combined with an immunotherapy called rituximab. Chemotherapy drugs work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Rituximab is a monoclonal antibody. It binds to a protein called CD20, which is found on B cells (a type of white blood cell) and some types of cancer cells. This may help the immune system kill cancer cells. Giving nivolumab with chemo-immunotherapy may help treat patients with PMBCL.

Inclusion Criteria: * Patient must have histologically confirmed primary mediastinal B-cell lymphoma (PMBCL) as defined by World Health Organization (WHO) criteria * Age 18-70 years old * Ejection fraction greater than 50% * ECOG 0-2 status * Signed informed consent * No severe concurrent illness * Measurable disease (at least one lesion that can be accurately measured in at least two dimensions on a CT scan, at least \>15 mm in largest diameter Exclusion Criteria: * Uncontrolled bacterial or fungal infection at the time of enrollment * Requirement for vasopressor support at the time of enrollment * Severe organ failure: creatinine more than 2 norms; ALT, AST more than 5 norms; bilirubin more than 1.5 norms * Karnofsky index \