Role of 18F-FDG PET/CT in Erdheim–Chester Disease in the Era of Multimodality Imaging

Abstract

Erdheim–Chester disease is a rare disease with systemic non-Langerhans cell histiocytosis, the diagnosis of which with conventional imaging modalities is challenging. We describe a case of a 73-year-old woman who was referred with a progressive history of bilateral proptosis. The magnetic resonance imaging (MRI) orbit demonstrated bilateral orbital masses with optic nerve encasement. A subsequent 18F-FDG PET/CT scan showed multi-organ disease with involvement of the orbits, pericardium, aorta, pararenal fascia, and appendicular bones. Metabolically active, easily accessible areas were selected for CT-guided biopsy. The biopsy showed sheets of foamy histiocytes with the expression of CD 68 and CD 163 consistent with a diagnosis of Erdheim–Chester disease. The FDG PET/CT played a pivotal role in establishing the diagnosis with the assessment of disease extent and further guided in the targeted biopsy.

Erdheim-Chester disease with tendon and muscle involvement: Reports of a rare presentation

“…For instance, in a study by Arnaud et al, sensitivity and specificity analyses compared 18 F-FDG PET/CT scan to CT or MRI, revealing nearly 100% specificity but variable sensitivity across organ systems. Moreover, 18 F-FDG PET/CT scan helps choose the best site for biopsy [23] . Additionally, previous observations suggested that 18 F-FDG PET/CT scan avidity may precede radiographic evidence of sclerosis in ECD, warranting exploration of whether avidity precedes changes in other imaging modalities in future studies [24 , 25] .…”

Paciente con enfermedad de Erdheim Chester diagnosticado a partir de lesión en sistema nervioso central

“…La infiltración de la grasa perirrenal y la fibrosis retroperitoneal puede ser observada mediante una TAC y el compromiso pericárdico o de aurícula derecha, en RMN cardíaca 8 . Sin embargo, el PET CT con F18 FDG tiene un papel fundamental al diagnóstico, ya que ayuda a determinar la extensión de la enfermedad, identificar posibles sitios de biopsia 9 , y también es de utilidad para evaluar la respuesta al tratamiento 10 .…”