There are approximately 5000-6000 new cases of UCD diagnosed per year in the United States, making it the most common form of<unk><unk> . UCD can occur at any age, but the median age at presentation is approximately 35 years old. There is a slightly increased incidence of UCD in women. There have been no published epidemiologic studies of<unk><unk>  outside of the United States; however, there is no evidence of increased or decreased incidence of<unk><unk>  in specific regions or ethnicities.
Unicentric Castleman disease
Idiopathic multicentric Castleman disease
Follicular lymphoma
Follicular dendritic cell sarcoma
Progressive nodular histiocytoma
Thymic carcinoma
Marginal zone B-cell lymphoma
Progressive nodular histiocytosis