Clinical, histological, and imaging characteristics of LCH of the central nervous system
| Lesion type and site . | Pathology . | MRI characteristics . |
|---|---|---|
| Tumorous lesions | ||
| Cerebral white and gray matter | Typical LCH morphology with CD1a/CD207 + histiocytes | Nodular or space-occupying lesions; T2 hyperintensity and T1 iso- or hypointensity; variably contrast enhancing; can present mass effect |
| LACI | ||
| Dentate nuclei of the cerebellum | Loss of Purkinje cells with gliosis in the cerebellar cortex | Bilateral and symmetrical slight T1-w hyperintensity, followed by development of T1-w hypointensity and/or T2-w hyperintensity |
| Infratentorial white matter (cerebellum, brainstem) | Neuroaxonal loss with secondary demyelination; pronounced inflammatory process dominated by CD8+ T-lymphocytes and microglial activation; BRAFV600E+ perivascular myeloid cells and increased frequency of BRAFV600E+ peripheral blood mononuclear cells (for patients with BRAFV600E+ systemic LCH) | Bilateral and symmetrical abnormalities (T2-w hyperintensity, T1-w isointensity or hypointensity) |
| Basal ganglia | — | Bilateral and symmetrical leukoencephalopathy-like abnormalities, or confluent lesions in a vascular pattern, with T2 hyperintensity and T1 hypointensity |
| Supratentorial white matter | Reactive gliosis and microglial activation decreased BRAFV600E+ cells compared with cerebellum/brainstem | Bilateral and symmetrical leukoencephalopathy-like abnormalities, or confluent lesions in a vascular pattern, with T2 hyperintensity and T1 hypointensity |
| Prominent, dilated perivascular spaces | ||
| Cerebral white matter | — | Bilateral and symmetrical punctate lesions in a vascular pattern. T2-w hyperintensity, and T1 iso- or hypointensity; variable contrast enhancement and mass effect |
| Lesion type and site . | Pathology . | MRI characteristics . |
|---|---|---|
| Tumorous lesions | ||
| Cerebral white and gray matter | Typical LCH morphology with CD1a/CD207 + histiocytes | Nodular or space-occupying lesions; T2 hyperintensity and T1 iso- or hypointensity; variably contrast enhancing; can present mass effect |
| LACI | ||
| Dentate nuclei of the cerebellum | Loss of Purkinje cells with gliosis in the cerebellar cortex | Bilateral and symmetrical slight T1-w hyperintensity, followed by development of T1-w hypointensity and/or T2-w hyperintensity |
| Infratentorial white matter (cerebellum, brainstem) | Neuroaxonal loss with secondary demyelination; pronounced inflammatory process dominated by CD8+ T-lymphocytes and microglial activation; BRAFV600E+ perivascular myeloid cells and increased frequency of BRAFV600E+ peripheral blood mononuclear cells (for patients with BRAFV600E+ systemic LCH) | Bilateral and symmetrical abnormalities (T2-w hyperintensity, T1-w isointensity or hypointensity) |
| Basal ganglia | — | Bilateral and symmetrical leukoencephalopathy-like abnormalities, or confluent lesions in a vascular pattern, with T2 hyperintensity and T1 hypointensity |
| Supratentorial white matter | Reactive gliosis and microglial activation decreased BRAFV600E+ cells compared with cerebellum/brainstem | Bilateral and symmetrical leukoencephalopathy-like abnormalities, or confluent lesions in a vascular pattern, with T2 hyperintensity and T1 hypointensity |
| Prominent, dilated perivascular spaces | ||
| Cerebral white matter | — | Bilateral and symmetrical punctate lesions in a vascular pattern. T2-w hyperintensity, and T1 iso- or hypointensity; variable contrast enhancement and mass effect |
Adapted from Yeh et al60 with permission.