LOW-GRADE ASTROCYTOMA WITH NEURAXIS DISSEMINATION AT DIAGNOSIS

Little is known about low-grade astrocytoma with neuraxis disseminatio n at diagnosis. A review of medical records identified this phenomenon in eight of 150 pediatric patients evaluated between 1985 and 1994 fo r histologically confirmed low-grade astrocytoma. These patients (five male and three female) ranged in age from 5 months to 20 years (media n 8 years). Symptoms of neuraxis disease were minimal or absent. Prima ry tumor sites were the hypothalamus in four cases, brainstem/spinal c ord in three, and temporal lobe in one. Patterns of dissemination (eva luated by computerized tomography and/or magnetic resonance imaging te chniques) appeared to be related to the primary site: hypothalamic tum ors metastasized along the ventricular cerebrospinal fluid pathways, a nd tumors in other locations disseminated along subarachnoid pathways. Following initial treatment with chemotherapy (in three), partial res ection (in one), radiation therapy (in three), and chemotherapy plus i rradiation (in one), four patients required salvage therapy for progre ssive or recurrent disease. Seven of the eight patients are alive with stable or progressive disease 6 to 105 months postdiagnosis (median 1 5 months). Low-grade astrocytoma with initial neuraxis dissemination i s responsive to chemotherapy and radiation, a proportion showing perio ds of stable disease. The optimum therapy or combination of therapies remains unclear.