[An intradiploic epidermoid cyst of the skull in infancy: case report].

An intradiploic epidermoid cyst of the skull in infancy is rare. We report a case of a 7-month-old girl with an intradiploic epidermoid cyst of the left parietal bone. The patient was admitted to the department of pediatrics in, our hospital in March, 2000, complaining of a lump in the scalp with a diameter of 1.5 cm. The pediatrician doubted that it was a case of Langerhans cell histiocytosis (LCH). In addition, as a result of further tests there were no systemic findings to suggest LCH. The skull x-ray showed round radiolucency of the left parietal bone. CT scans showed an iso density intradiploic mass with destruction of the outer table. Because of the fact that the mass was enlarging, the patient was admitted to our neurosurgical service in April, 2000. We excised the lesion to confirm the histological findings. The histological diagnosis was epidermoid cyst. We discuss the clinical feature and treatment strategy for intradiploic epidermoid cyst in infancy.