Attention! Cardiac tamponade may be caused by underlying Castleman's disease.

Castleman's disease is a rarely observed lymphoproliferative disease. In the literature, various signs and symptoms of the disease have been reported; one of these is secondary cardiac tamponade. We describe the case of a 41-year-old man who developed cardiac tamponade during examination, and who was later diagnosed with Castleman's disease, based on his lymph node biopsies.