Leukemic infiltration of the cerebellum in acute myelomonocytic leukemia.

A 31-year-old woman with acute myelomonocytic leukemia presented with meningeal signs and a cerebellar mass attributed to leukemic infiltration. The mass disappeared with radiation therapy and intraventricular chemotherapy, but the patient subsequently suffered several spinal nerve root recurrences, disseminated herpes zoster, and progressive multifocal leukoencephalopathy. At autopsy, there was no trace of the meningeal leukemia or cerebellar infiltrate. This case illustrates several of the neurologic complications of acute nonlymphocytic leukemia, and raises the question whether patients with the myelomonocytic form of this disease might benefit from prophylactic central nervous system treatment.