Abstract
Sarcoidosis and Crohns disease have been associated with increased long term risk of lymphoproliferative disorders, including lymphomas. Newly developed lymphadenopathy in a patient with these disorders should prompt pathological evaluation. Castleman's disease is a lymphoproliferative disorder characterized by enlarged hyperplastic lymph nodes with regressed follicles surrounded by expanded mantle zones of small lymphocytes, and interfollicular vascular proliferation in the hyaline-vascular type. Similar to sarcoidosis and Crohns disease, its etiology is incompletely understood, although immune dysregulation, genetic factors and infectious and environmental factors are thought to play a role in all three diseases. Interleukin-6 is a possible pathological common factor between these three disease processed. Unicentric, hyaline-vascular type Castleman's disease can be treated successfully with complete surgical resection. We report a patient with long history of sarcoidosis and Crohns disease with newly developed lymphadenopathy which was found to be due to Castleman's disease.