Lymphomatoid granulomatosis (CNS manifestations)

Lymphomatoid granulomatosis of the central nervous system is uncommon, but represents the second most common site of involvement in patients with systemic lymphomatoid granulomatosis, after the lungs, which are most commonly involved. In the 2021 (5th edition) WHO classification of CNS tumours it is considered one of the CNS lymphomas ³. 

For a general discussion of the underlying condition, including epidemiology and pathology, please refer to the article lymphomatoid granulomatosis. 

Epidemiology

Lymphomatoid granulomatosis of the CNS most commonly affects adults (40-60 years of age) and is more common in immunocompromised individuals ⁴.

Clinical presentation

Neurologic symptoms are fairly common, seen in around 30% of cases, usually in the setting onof systemic or cutaneous symptoms ¹. The specifics of the presentation will depend on the location of disease within the central nervous system.

Pathology

Like other immunodeficiency-associated CNS lymphomas, lymphomatoidLymphomatoid granulomatosis is frequently EBV-associated ³⁴. The lesions are composed of large EBV-positive tumour B cells admixed with infiltrating plasma cells and lymphocytes (CD4+ and CD8+ T-lymphocytes). They are typically angiocentric or angiodestructive ³⁴. 

Radiographic features

MRI is the modality of choice for assessing patients with suspected lymphomatoid granulomatosis. 

MRI

Appearances are very variable with lesions seen in all compartments (supra- and infratentorial) and demonstrating a wide range of morphology.

Generally, lesions are located in the periventricular white matter but can extend to involve cortex.

Punctate or linear T2 hyperintensities within perivascular spaces are also characteristic and show contrast enhancement ^1,2. Larger lesions may be solid or demonstrate ring enhancement. They have variable surrounding oedema and may be associated with leptomeningeal enhancement ¹.