Orbital histiocytosis with systemic involvement: A case with complex affiliations

Area of Science:

• Ophthalmology
• Oncology
• Pathology

Background:

• Orbital masses can present with diverse etiologies, posing diagnostic challenges.
• Distinguishing between rare fibrohistiocytic and lymphoproliferative disorders is crucial for appropriate management.
• Systemic involvement in orbital diseases requires comprehensive evaluation.

Observation:

• A 70-year-old male with multiple comorbidities presented with orbital masses.
• Initial biopsy suggested xanthogranuloma or Erdheim-Chester disease (ECD); subsequent biopsy indicated Rosai-Dorfman disease (RDD).
• The patient developed constrictive pericarditis and retroperitoneal fibrosis, with unsuccessful responses to various treatments.

Findings:

• Orbital RDD diagnosis was established despite atypical clinical and pathological findings.
• Immunohistochemistry confirmed RDD with CD68 and S100 positivity, and CD1a negativity.
• Concurrent ECD was considered but orbital findings were attributed to extranodal RDD.

Implications:

• This case highlights the importance of thorough histopathological evaluation for orbital masses.
• Atypical presentations of RDD can mimic other systemic diseases, necessitating careful differential diagnosis.
• Understanding extranodal RDD variants is crucial for managing complex cases with poor treatment response.