Loncastuximab Tesirine and Rituximab Following Stereotactic Radiosurgery in Patients With Central Nervous System Lymphomas (SOLAR)

This study — called SOLAR — tests combining a targeted radiation technique (stereotactic radiosurgery, or SRS) with two cancer drugs — loncastuximab tesirine (an antibody-drug conjugate) and rituximab — in patients with lymphoma affecting the brain or central nervous system (CNS). The goal is to improve outcomes for a disease that is difficult to treat. **You may be eligible if...** - You are 18 years or older - You have a confirmed diagnosis of primary CNS lymphoma OR diffuse large B-cell lymphoma (DLBCL) that has spread to the brain - Your disease has either relapsed/progressed after at least one prior treatment, OR you are unable to receive high-dose methotrexate (the standard first-line treatment) - You are a candidate for stereotactic radiosurgery (SRS) - You have acceptable organ function and performance status **You may NOT be eligible if...** - Your performance status is too poor (ECOG score above 3) - You have conditions that make either drug or SRS unsafe Talk to your doctor to see if this trial is right for you.