[Acute myeloid leukemia invasion of the central nervous system, detected only along the Virchow Robin space].

A 66year-old man with sustained fever was diagnosed as having acute myeloid leukemia with multilineage dysplasia. Induction therapy with etoposide and AraC was initiated, but was ineffective. Although fever had persisted for more than a few days, there was no evidence of any infection on radiological examination or culture studies. The patient was disorientated and demonstrated personality change. After a severe convulsive seizure, the patient died. Autopsy findings showed that the leukemic cells had permeated the Virchow Robin space, but without a mass lesion in the cerebral parenchyma. He was diagnosed as having had central nervous system leukemia (CNSL) that provoked sustained fever, consciousness disturbance and convulsive seizure. These findings suggested that the Virchow Robin space plays a particular role in the development of CNSL. Even with repeated cerebrospinal fluid examinations and radiological tests, we were unable to correctly diagnose CNSL before death, which may indicate the intractability of diagnosing CNSL spread along the Virchow Robin space. This case provides useful information about the pathophysiology and diagnosis of CNSL.