Rosai-Dorfman Disease FDG PET/CT Findings in a Patient Presenting With Pyrexia and Cervical Adenopathy

Sinus histiocytosis with massive lymphadenopathy or Rosai-Dorfman disease is a rare clinicopathological entity that typically affects young adults, with patients presenting frequently with fever and painless cervical adenopathy. It can mimic lymphoproliferative diseases, and FDG PET/CT typically demonstrates significant FDG avidity in areas of disease. We report a case of a young Chinese woman presenting with pyrexia and painless cervical adenopathy, for which FDG PET/CT performed as part of the diagnostic process demonstrated FDG avid lesions in both nodal and extranodal sites.