Castleman disease presenting in the neck: report of a case and review of the literature.

Castleman disease is a rare lymphoproliferative disorder with two primary subtypes that vary in presentation and course. Unicentric Castleman disease (UCD) presents as a solitary mass, most commonly in the mediastinum, and rarely in the head and neck. In contrast to multicentric Castleman disease (MCD), which features peripheral lymphadenopathy and numerous systemic symptoms, UCD is not typically associated with generalized symptoms. Here, we present an unusual case of UCD presenting as a slowly expanding, isolated neck mass in a 29-year-old woman. This case demonstrates the distinguishing clinical, radiologic, and histologic findings unique to UCD, which is often misdiagnosed as lymphoma or other malignant process. These findings stand in contrast to those observed in MCD patients, and hence, offer insight into the practical aspects of diagnosis and management of Castleman disease in the head and neck.