RESUMO
BACKGROUND: Growing teratoma syndrome(GTS)is the progression of a mature teratoma during or following radiochemotherapy for germ cell tumors. We report two surgical cases of GTS. CASE 1: A 24-day-old new-born presented with vomiting and head enlargement. Blood alfa-feto protein(AFP)and beta-human chorionic gonadotropin(ß-hCG)were within or at the upper limits of the normal ranges. Magnetic Resonance Imaging(MRI)demonstrated a large mass in the posterior fossa causing the severe hydrocephalus. Tumor removal was immediately performed. Histological diagnosis given was immature teratoma. While chemotherapy effectively reduced the level of tumor makers, multiple recurrence was noticed on MRI 70 days after the surgery. GTS was suspected and total removal was performed. Histological examination revealed a mature teratoma. The patient is growing normally thereafter, 2.5 years after the onset. CASE 2: A 16-year-old male presented with binasal hemianopsia. Blood AFP and ß-hCG were within or at the upper limits of the normal ranges. MRI demonstrated an intrasellar mass protruding upward. Tumor removal was performed and histological diagnosis given was mixed germ cell tumor. While radiochemotherapy effectively normalized the tumor makers, recurrence was noticed on MRI 190 days after the surgery. Total removal was performed with the diagnosis of GTS. Histological examination revealed a mature teratoma. The patient lives a normal school life thereafter as followed up after a year after the onset. CONCLUSION: It is important to diagnose and perform the surgery early enough to enable total removal of the mass presenting as GTS because total surgical removal is the only treatment for GTS.