Immunohistochemical detection of carbohydrate determinant 19-9 (CA 19-9) in intracranial epidermoid and dermoid cysts.

We evaluated carbohydrate antigen (CA) 19-9 levels of intracranial dermoid and epidermoid cyst in serum and intratumoral tissue. The preoperative serum levels were mildly to moderately higher than their normal ranges in four of seven patients. In four patients with high serum CA 19-9 levels, they returned to normal ranges in three who had the cyst resected totally and remained slightly high in one with residual cyst. Immunohistochemical studies using anti-CA 19-9 antibody demonstrated positively stained capsule and keratinous tissue. Serum CA 19-9 levels of intracranial dermoid or epidermoid cysts with more teratomatous components may be elevated above normal levels.