Familial epidermoid cysts of the spleen: report of two cases.

The familial occurrence of epidermoid cysts of the spleen is rare, with only six cases having ever been reported, to our knowledge. We recently diagnosed epidermoid cysts of the spleen in a mother and son. First, a 15-year-old boy was admitted to our hospital for management of blunt abdominal trauma. Computed tomography (CT) showed a ruptured large splenic cyst with an intraabdominal hematoma. We performed a splenectomy, and histopathological examination confirmed the existence of an epidermoid cyst of the spleen. About 2 years and 6 months later, the family physician found that the patient's 41-year-old mother had a large splenic cyst, and she was referred to our hospital for further investigation. CT showed a 10 x 8 cm cyst occupying most of the spleen. The patient underwent splenectomy, and a pathological diagnosis of an epidermoid cyst of the spleen was confirmed. Although the etiology of epidermoid cysts of the spleen is unclear, this familial occurrence may support the hypothesis of congenital malformation as a result of genetic change.