Leptomeningeal precursor B-cell lymphoblastic lymphoma in a child with minimal bone marrow involvement.

The authors report an unusual presentation of a leptomeningeal lymphoblastic lymphoma in a 6-year-old boy with headache and papilledema as the only initial manifestations. The diagnosis was confirmed by the presence of precursor B-cell lymphoblasts in the cerebrospinal fluid, with no cerebral mass and with only 9% phenotypically identical blasts in the bone marrow. This patient was treated on a high-risk ALL protocol with intensive systemic/intrathecal chemotherapy plus cranial irradiation, and he remained in complete remission 6 months after his initial diagnosis.