P.108 Diffuse large B-cell Lymphoma secondary to iatrogenic immunosuppression with unusual MRI findings and literature review

Background: Immunosuppressive therapy is a risk factor for lymphoproliferative disorders. We present a case of primary CNS B-cell lymphoma in the setting of iatrogenic immunosuppression from azathioprine usage. A literature review is provided. Methods: Case report Results: 64-year-old male presents with several weeks of cognitive decline, impaired speech, and headache with a history of ulcerative colitis (on azathioprine and 5-ASA) with no radiological evidence of systemic malignancy. MR showed left frontal extra-axial mass (4.0 x 2.4 x 4.0 cm) with heterogeneous enhancement of a solid component with local dural thickening. The enhancing mass had solid and cystic components. Radiological differential included dural metastasis, atypical meningioma or unusual intra-axial mass including GBM with some dural involvement. He underwent surgical resection, which showed a primary CNS lymphoma, diffuse large B-cell, CD 20 + and EBV +. Post-operatively his cognition improved. Azathioprine was stopped and 5-ASA was increased. He proceeded with MPVC (methotrexate, procarbazine, vincristine, and cytarabine) chemotherapy. Conclusions: Our case shows isolated extra-nodal CNS manifestation of lymphoma in the context of immunosuppressive medications with strikingly atypical MR findings leading to a pre-operative diagnostic dilemma. Treatment is challenging and needs to be individually tailored due to a need for stopping immunosuppressive agents in conjunction with CNS lymphoma treatment.