Ependymal cyst producing alpha-fetoprotein - Case report

This 17-year-old man was admitted to the hospital due to progressive headac he and diplopia. Neuroradiological studies revealed a cystic mass in the pi neal region without a parenchymal lesion. In addition, serum alpha-fetoprot ein (AFP) levels were elevated. A cyst-to-third-ventricle and cistern fenes tration was performed, but the cyst enlarged 3 months after the first opera tion. In the second operation, subtotal resection of the cyst was performed . The AFP level in the cyst fluid was very high preoperatively but was decr eased postoperatively. The patient was discharged with no neurological defi cit. Pathological examination of resected tissue showed a single layer of c uboidal cells that resembled an ependymal structure. The cells were immunor eactive for AFP immunostain, which indicated AFP production from these cell s.