Epidermoid cyst of the occipital bone.

This case illustrates the classic presentation, investigation, and management of diploic epidermoid cysts. It is important to consider this condition in the differential diagnosis of a scalp mass that is deep, nonmobile, and in the frontal, parietal, and occipital regions. If suspected, skull radiographs will provide invaluable information, and if a diploic epidermoid cyst is present, they will direct further management.