The authors report the case of a 58 year old woman with a 5 year history of Waldenström's disease, who presented with perivascular confluent and multifocal lymphoproliferative cerebral involvement (Bing and Neel syndrome). The lymphoproliferative process was limited to the brain matter and respected the meninges, posing the problem as to its origin. It resulted in a tumoral syndrome with intracranial hypertension leading to coma and death after 6 months. This case is reviewed in the light of two similar cases in the medical literature.