Isolated secondary CNS relapse in a case of stage I diffuse large B-cell lymphoma.

A 55-year-old woman was admitted to our hospital with a 10-day history of right arm weakness and numbness. The patient's medical history was notable for lobular carcinoma in situ of the right breast in 2008 and stage I diffuse large B-cell lymphoma of the left axilla. The patient had completed treatment with chemotherapy and radiation 2 months prior to presentation. Blood counts, metabolic panel and lumbar puncture were unremarkable. MRI of the brain revealed multiple enhancing masses. The patient was started on dexamethasone, with rapid symptom improvement. A stereotactic brain biopsy revealed CD20 diffuse large B-cell lymphoma. The patient was started on high-dose intravenous methotrexate. She has received 11 cycles and has regained near normal function of the right arm. The patient's most recent brain MRI showed near complete resolution of all previously seen abnormal foci of enhancement.