Castlemans disease (angiofollicular lymph node hyperplasia)?
Castleman’s disease is a heterogeneous group of lymphoproliferative disorders that share histopathologic features including germinal-center formation and marked capillary proliferation. There are three subtypes:
- • Unicentric: involves one or more lymph nodes in one region of the body. The histopathology can vary between hyaline vascular subtype (90%) and plasma cell subtype (10%). Patients usually do not have systemic features.
- • Multicentric: presents with lymphadenopathy in multiple regions of the body. The histopathology can vary between hypervascular subtype and plasma cell subtype. Half the patients with multicentric disease will have a human herpes virus (HHV)-8 infection and be immunocompromised (usually HIV-infected), and half of the patients will have no evidence of HHV-8 or HIV infection. Some of these patients without evidence of a viral infection will have an associated POEMS syndrome.
- • Patients who have the plasma cell subtype of multicentric Castleman’s disease frequently have systemic symptoms which can mimic autoimmune diseases including fever, night sweats, hepatosplenomegaly, cytopenias, elevated ESR, autoantibodies (Coombs, ANA), and a polyclonal gammopathy.
- • Patients with symptomatic multicentric Castleman’s disease who are not infected with HHV-8 can be treated with anti-IL6 therapy (siltuximab or tocilizumab). Rituximab is used as first-line therapy in those infected with HHV-8. Patients with HHV-8 infections or POEMS receive additional directed therapy (e.g., antivirals or plasma cell-directed therapy).