This study was designed to evaluate the characteristics of malignant germ cell tumors (MGCT) in pediatric patients. Medical records of 71 children who had MGCT from 1985 to 1994 were reviewed. The mean age was six years and the sex ratio (male:female) was 3:4. According to the histologic classification, the most common MGCT was the malignant teratoma and the next was the endodermal sinus tumor. The malignant teratoma, the endodermal sinus tumor and the embryonal carcinoma appeared to be more commonly distributed in the young age. The clinical presentations were varied and depended on the primary site. Thirty-nine cases of MGCT originated from gonads and the other thirty-two cases were extragonadal tumors. All of dysgerminoma and gonadal mixed germ cell tumors developed from ovaries; however, all of gonadal embryonal carcinoma developed from the testes.
Preoperative levels of serum-fetoprotein (AFP) were significantly increased in all of the endodermal sinus tumors, the embryonal carcinomas, the mixed germ cell tumors and in 69% of the malignant teratoma. Serum -human chorionic gonadotropin (HCG) were increased in all of the oriocarcinomas, in 83% of the dysgerminomas and in 11% of malignant teratoma. The malignant teratoma had the best prognosis. Although the MGCTs were rare in the pediatric age and their histologic subtypes were variable, each tumor had its specific characteristics according to histologic classification, the age of onset, the primary site and the secreting tumor markers. Therefore, these specific features should be considered for the diagnosis and management of MGCT in children.