Ibrutinib Combination Therapy in Transplant Ineligible Individuals With Newly Diagnosed Primary CNS Lymphoma

This study tests a combination of drugs — ibrutinib, rituximab, and high-dose methotrexate — in patients with a rare type of lymphoma that starts in the brain or spinal cord (called primary CNS lymphoma), who are not able to undergo stem cell transplantation. **You may be eligible if...** - You have been diagnosed with primary CNS lymphoma (a lymphoma in your brain or spinal cord), confirmed by biopsy or fluid sample - You are 18 years or older - You are not eligible for high-dose chemotherapy and stem cell transplant — either because you are 65 or older or because of other health conditions - Your doctor considers you healthy enough to receive this treatment combination **You may NOT be eligible if...** - You are able to and would be considered for a stem cell transplant - You have not been diagnosed with CNS lymphoma Talk to your doctor to see if this trial is right for you.