Multicentric Plasma-Cell Type Castleman Disease Masquerading As Hodgkin Lymphoma: A Case Report.

Castleman disease (CD), or angiofollicular hyperplasia, or giant lymph node hyperplasia, is a heterogeneous benign lymphoproliferative disorder of unknown etiology. It has three distinct histologic subtypes (hyaline vascular, plasma cell, and mixed hyaline vascular plasma cell types) as well as unicentric Castleman disease (UCD) and multicentric Castleman disease (MCD) variants. In the unicentric form, the disease is confined to one anatomical lymph node and usually with no systemic symptoms. However, in the multicentric form (further subdivided into idiopathic MCD, human herpes virus-8-associated MCD, and POEMS-associated MCD), lymphadenopathy is more generalized with more aggressive systemic symptoms mimicking a malignant lymphoma. Therefore, this case report aims to underscore the importance of immunohistochemical evaluation as an indispensable ancillary technique to routine histopathological examination of a lymph node biopsy specimen, as a gold standard for definitive diagnosis of proliferative lymph node lesions.