Erdheim-Chester manifesting purely as a neurological disease

A 60-year-old man presented with vertigo, paraparesis, and dysarthria that evolved over 3 months. A magnetic resonance imaging (MRI) scan revealed nodular masses in the pons, peduncles, and cerebellar hemispheres, indicating a metastatic neoplasm (Figure 1). A craniectomy was performed, showing dense histiocyte proliferation, Touton giant cells, and lymphocytic infiltrate consistent with Erdheim-Chester disease (Figure 2). The cytogenetic analysis confirmed a BRAF V600 mutation. Vemurafenib therapy was initiated. Six months later, the patient still exhibited dyslalia and left hemiparesis, and a follow-up MRI scan was performed, revealing an area of sequelae (Figure 3). Erdheim-Chester disease is a rare non-Langerhans histiocytosis, with neurological symptoms occurring in 41% of the cases.¹, ²

Figure 1
Magnetic resonance imaging scan showing expansive intraparenchymal nodular lesions located in the posterior fossa, involving the pons, peduncles, and cerebellar hemispheres, presenting mild hypointense signal in the T2-weighted sequence (A) and vasogenic edema characterized by marginal fluid-attenuated inversion recovery (FLAIR) hypersignal (B) and intense contrast enhancement (C,D).

Figure 2
Erdheim-Chester disease in the cerebellum. (A) An infiltrate of histiocytes with a bland appearance and giant cells associated with a sparse lymphoplasmacytic infiltrate (hematoxylin and eosin staining; magnification: 4x). (B) Histiocytes characterized by abundant foamy (xanthomatous) (arrows) cytoplasm with surrounding fibrosis (hematoxylin and eosin staining; magnification: 100x). (C) Touton giant cells are frequently present(*) (hematoxylin and eosin staining; magnification: 100x).

Figure 3
Images after the treatment with vemurafenib showing an area of sequelae in the left cerebellar hemisphere, characterized by volumetric reduction and T2/FLAIR hyperintensity (A-C), with resolution of expansile lesions in the posterior fossa and regression of enhancement (D).

Data Availability Statement

Data is available from the corresponding author upon reasonable request.

References

• ¹ Benson JC, Vaubel R, Ebne BA, Mark IT, Celda MP, Hook CC, et al. Erdheim-Chester Disease. AJNR Am J Neuroradiol 2023;44(05): 505-510. Doi: 10.3174/ajnr.A7832
  » https://doi.org/10.3174/ajnr.A7832
• ² Haque A, Pérez CA, Reddy TA, Gupta RK. Erdheim-Chester Disease with Isolated CNS Involvement: A Systematic Review of the Literature. Neurol Int 2022;14(03):716-726. Doi: 10.3390/neurolint14030060
  » https://doi.org/10.3390/neurolint14030060

Edited by

• Editor-in-Chief:
  Hélio A. G. Teive https://orcid.org/0000-0003-2305-1073.

• Associate Editor:
  Leandro Tavares Lucato https://orcid.org/0000-0001-9181-5245.

Publication Dates

• Publication in this collection
  14 July 2025
• Date of issue
  2025

History

• Received
  07 Mar 2025
• Reviewed
  08 Apr 2025
• Accepted
  17 Apr 2025