September 19, 2019
A 51-year-old man, diagnosed with Waldenstrom’s macroglobulinemia 15 years prior, presented with progressive memory loss and episodes of spatial disorientation for the past 2 months.
Bing-Neel syndrome (BNS)
- Background
- Bing-Neel syndrome (BNS) is a very rare complication of Waldenstrom’s macroglobulinemia (WM) due to lymphoplasmacytoid infiltration and IgM deposition in the CNS.
- Two distinct forms have been described: tumoral and diffuse infiltrative.
- Clinical Presentation
- The neurologic presentation tends to develop over a period of weeks to months and can be extremely variable, depending on the location and extension of the lesion(s).
- Parenchymal involvement can present with seizures, weakness, aphasia, memory deficits, psychiatric symptoms, or even coma. In meningeal forms patients usually present with cranial nerves palsies, headache and vomiting.
- Sensory deficits and weakness are suggestive of spinal cord involvement.
- Key Diagnostic Features
- Bing-Neel syndrome should be considered in patients with WM and neurologic symptoms.
- MRI has a major role in investigation of suspected BNS and usually reveals subcortical mass-like lesion(s) with high signal on T2 and FLAIR, iso/hypointensity on T1 and contrast enhancement after gadolinium.
- In diffuse infiltrative form, leptomeningeal thickening with contrast enhancement are usually present.
- Differential Diagnosis
- Differential diagnosis of BNS include vascular, infectious/inflammatory and neoplastic processes.
- In leptomeningeal involvement, pyogenic and granulomatous meningitis and leptomeningeal carcinomatosis should be considered. In its tumoral form, BNS may mimic neoplastic lesions such as low-grade gliomas.
- CSF should be analysed and if inconclusive, biopsy should be considered to rule out alternative infectious or neoplastic processes.
- History of Waldenstrom’s macroglobulinemia is key for suspecting this diagnosis as imaging findings overlap significantly with the previously mentioned entities.
- Treatment
- Treatment remains challenging due to the rarity of the syndrome.
- Chemotherapeutic agents have been used, sometimes combined with intrathecal treatment in cases of meningeal involvement.
- Due to its neurotoxicity radiotherapy is not recommended as first-line therapy, being reserved for patients failing other treatment options.
