Cerebral spinal fluid involvement by Hodgkin's disease diagnosed by CSF cytology and immunocytochemistry

A 39-yr-old man with stage IV Hodgkin's disease (HD) involving bone marrow was being evaluated for autologous bone marrow transplantation when he developed diplopia, prompting a lumbar puncture tap for cerebral spinal fluid (CSF) examination. Cytologic examination of the CSF revealed numerous Reed-Sternberg (RS) cells in a polymorphous inflammatory background of small lymphocytes, monocytes, rare plasma cells, and eosinophils. However, magnetic resonance imaging (MRI) studies of the brain and spinal cord failed to reveal evidence of leptomeningeal disease or intracranial masses. Repeat CSF examination again demonstrated cytologic evidence of HD. Immunocytochemical stains established that the RS cells and mononuclear Hodgkin's cells were positive for CD30 and CD20 but negative for CD15; this phenotype was identical to that of RS cells in the initial diagnostic bone marrow biopsy, confirming CSF involvement by HD. The patient was treated with intrathecal methotrexate, 15 mg, 6 days after his bone marrow transplant. After treatment, all subsequent CSF cytology specimens were negative for tumor. In this case of disseminated HD, cytologic examination allowed for early detection of CNS involvement by lymphoma prior to development of radiographically detectable lesions.