Growing teratoma syndrome: an unusual evolution of treated ovarian immature teratoma - a case report

Growing teratoma syndrome (GTS) is a rare condition among germ cell tumor (GCT) patients during treatment with systemic chemotherapy. It is characterized by the development of enlarging masses, the normalization of tumor markers, and the presence of only mature teratoma in the pathological specimen. The authors present the unusual case of a 15-year-old girl with an immature teratoma treated with conventional surgery and systemic chemotherapy. On her follow up, although tumor markers returned to normal, there was an enlargement of abdomino-pelvic masses confirmed by a PET/TC study. With the diagnosis of a GTS, the patient underwent a com- plete cytoreduction. Histologically, all the specimens contained mature teratoma tissue. The patient remains clear with no signs of recurrence with no further treatment. The knowledge and awareness of this syndrome are highlighted in order to prevent further unnecessary chemotherapy and allow an optimal cytoreduction, which seems to be the most effective therapy so far.