Feasibility of Acquiring Hyperpolarized Imaging in Patients With Primary CNS Lymphoma

PRIMARY OBJECTIVES 1. To determine the safety and tolerability of hyperpolarized 13C MR metabolic imaging as a new and unique tool in the evaluation of tumor burden and detecting early response to standard therapy in participants with PCNSL. 2. To assess the feasibility of hyperpolarized 13C as a new and unique tool in the evaluation of tumor burden and detecting early response to standard therapy in PCNSL participants. 3. To define the most appropriate imaging parameters for obtaining 13C data from PCNSL participants (Cohort 1, n=5). 4. To evaluate changes in Cohort 2 in imaging pre- and post- high-dose methotrexate, temozolomide plus rituximab (MTX-R) based therapy using the parameters found in Cohort 1 EXPLORATORY OBJECTIVES 1. To test the hypothesis that genetic markers of nuclear factor kappa light chain enhancer of activated B cells (NF-kB) activation in PCNSL diagnostic specimens correlate with high lactate signal on metabolic imaging and with high cerebrospinal fluid (CSF) lactate concentration on baseline pre-treatment CSF evaluation. 2. To test the hypothesis that genetic markers of NF-kB activation correlate with a smaller decrease in lactate on repeat metabolic magnetic resonance (MR) imaging and in repeat CSF evaluation after standard induction methotrexate-based therapy and that genetic markers of NF-kB activation and high lactate signals correlate with lower rate of complete radiographic response on conventional MRI and shorter progression-free survival (PFS). OUTLINE: Participants are assigned to 1 of 2 cohorts. COHORT I: Participants receive hyperpolarized carbon C 13 pyruvate intravenously (IV) and undergo MRI at baseline. An optional second HP 13C pyruvate injection and MRI acquisition will be offered on same day following completion of the first scan. COHORT II: Participants receive hyperpolarized carbon C 13 pyruvate IV and undergo MRI at baseline, up to 2 weeks after finishing 3 cycles of standard high-dose methotrexate, temozolomide plus rituximab therapy, and at disease progression (if applicable). An optional second HP 13C pyruvate injection and MRI acquisition will be offered on same day following completion of the first scan. Participants are followed for 1 hours after injection for adverse events. After completion of study, participants in Cohort 2 are followed up every 3 months for 2 years after completion of therapy, every 6 months for the next 3 years, and then annually for the next 5 years.