Late-onset Bing-Neel syndrome associated with delirium and Lewy body dementia

Bing-Neel syndrome, a rare complication of Waldenström macroglobulinemia: analysis of 44 cases and review of the literature. A study on behalf of the French Innovative Leukemia Organization (FILO)

Central nervous system involvement by malignant cells is a rare complication of Waldenström macroglobulinemia, and this clinicopathological entity is referred to as the Bing-Neel syndrome. There is currently no consensus on the diagnostic criteria, therapeutic approaches and response evaluation for this syndrome. In this series, we retrospectively analyzed 44 French patients with Bing-Neel syndrome. Bing-Neel syndrome was the first manifestation of Waldenström macroglobulinemia in 36% of patients. When Waldenström macroglobulinemia was diagnosed prior to Bing-Neel syndrome, the median time interval between this diagnosis and the onset of Bing-Neel syndrome was 8.9 years. This study highlights the possibility of the occurrence of Bing-Neel syndrome without any other evidence of progression of Waldenström macroglobulinemia. The clinical presentation was heterogeneous without any specific signs or symptoms. Biologically, the median lymphocyte count in the cerebrospinal fluid was 31/mm(3). Magnetic resonance imaging revealed abnormalities in 78% of the cases. The overall response rate after first-line treatment was 70%, and the overall survival rate after the diagnosis of Bing-Neel syndrome was 71% at 5 years. Altogether, these results suggest that Bing-Neel syndrome should be considered in the context of any unexplained neurological symptoms associated with Waldenström macroglobulinemia. The diagnostic approach should be based on cerebrospinal fluid analysis and magnetic resonance imaging of the brain and spinal axis. It still remains difficult to establish treatment recommendations or prognostic factors in the absence of large-scale, prospective, observational studies.

Bing-Neel syndrome: Two unexpected cases and a review of the literature

Waldenström macroglobulinemia (WM) is a lymphoplasmacytic lymphoma characterized by the proliferation of small B-lymphocytes in the bone marrow that produce monoclonal immunoglobulin M (IgM). We describe two patients with WM who presented with neurological symptoms due to infiltration of lymphoplasmacytoid tumor cells in the central nervous system, a condition known as Bing-Neel syndrome. A literature review revealed that this syndrome is rare and commonly missed in clinical practice due to its variable presentation and a lack of awareness or knowledge. Brain and spinal magnetic resonance imaging may show a focal mass or diffuse infiltration. The diagnosis of Bing-Neel syndrome requires proof of IgM or lymphoplasmacytoid cells in cerebrospinal fluid or in a brain biopsy. Treatment with intravenous and/or intrathecal chemotherapy and cranial radiotherapy is described in literature with generally poor outcome, although a combination of these therapies seems to improve outcome. Nevertheless, insufficient data are currently available to make general treatment recommendations.