The full spectrum of Castleman disease: 273 patients studied over 20 years

Summary The spectrum of Castleman disease (CD) has considerably extended since its first description in 1956. Recently, an international collaborative working group has reached consensus on the diagnostic criteria and classification of CD. We herein report 273 patients with lymph node histopathology consistent with CD and investigate the newly established diagnostic criteria. Twenty of these patients with Castleman‐like histopathology were removed from analyses, because they were diagnosed with an exclusionary disorder (18 with haematological malignancy). Among the 253 remaining patients, 57 were considered unicentric CD (UCD), 169 were multicentric CD associated with Human Herpesvirus 8 (HHV‐8+MCD), including 140 patients with human immunodeficiency virus (HIV) infection and 29 patients without HIV infection, and 27 were HHV‐8 negative/idiopathic multicentric CD (iMCD). 2‐( 18 F)fluoro‐2‐deoxy‐D‐glucose positron emission tomography/computed tomography was useful in 62 patients for staging/classification of the disease and for excluding associated lymphoma. UCD was mainly associated with hyaline‐vascular histopathological features, and most patients were asymptomatic. Of the 27 patients that we had originally diagnosed with iMCD, 26 met the newly established diagnostic criteria. Patients with iMCD and HHV‐8+ MCD demonstrated similar characteristics, including fever, splenomegaly, cytopenia and inflammatory symptoms. However, the disease was more aggressive in HHV‐8+ MCD, particularly in HIV‐infected patients.