Case of germ cell tumor of the pineal region with elevation of serum and csf alpha-fetoprotein levels following histological change

Abstract

A 12-year-old boy with a germ cell tumor in the pineal region showed elevation of serum and cerebrospinal fluid (CSF) alpha-fetoprotein (AFP) levels following histological changes. The histological diagnosis of the specimen resected in the first operation was a typical germinoma, and AFP levels in both serum and CSF were within normal limits. A heterotopically recurrent tumor was removed 22 months after the first surgery. The histology of the tumor changed into that of a endodermal sinus tumor (yolk sac tumor) with a teratomatous elements according to Teilum's classification. AFP levels of both serum and CSF stayed high (500-600 ng/ml) from the time of the second admission to death. Elevated AFP levels in intracranial germ cell tumors have been reported in endodermal sinus tumors (yolk sac tumor), embryonal carcinoma and immature (malignant) teratoma, but not in germinoma and mature (benign) teratoma. AFP estimation in the serum and CSF is valuable not only in diagnosis, but also in monitoring the results of therapy and assessing the presence of recurrences.