Pure pediatric ovarian immature teratomas: The French experience.

Objective: To describe characteristics and outcome of pediatric ovarian immature teratomas (IT) to better define the place of chemotherapy.

Methods: Children with ovarian IT enrolled in TGM95 and TGM2013 studies were analyzed. Norris grading and International Federation of Gynecology and Obstetrics staging system were used.

Results: Thirty-six cases were identified with a median age of 11 years (range = 1-18): 35 of 36 stage I (17 stage IA, 13 stage IC, and 5 stage IX), including seven patients with gliomatosis peritonei (GP), and 1 stage IIIB (IT peritoneal implants). Centrally reviewed Norris grading was performed in 31 cases: 14 grade I and 17 grade II/III tumors. All patients underwent upfront surgery: 19 unilateral oophorectomy, 14 unilateral adnexectomy, 2 unilateral cystectomy, and 1 bilateral cystectomy. No extensive GP surgery was performed. Six patients received adjuvant vinblastin, bleomycin, and cisplatinum because of tumor rupture (n = 5, including two patients with GP) or stage III (n = 1). After a median follow-up of 39.5 months (range = 6-238), two events occurred 10 and 11 months after diagnosis: one bilateralization (initial stage IX, grade I) and one IT peritoneal relapse (initial stage IA, grade II), respectively. Both were successfully rescued by platinum-based chemotherapy and delayed surgery. No stage IC patients treated without adjuvant chemotherapy relapsed (four grade I and three grade III). None of the seven patients with GP progressed. Five-year event-free survival and overall survival were 94% (95% CI = 81-98%) and 100%.

Conclusions: The current series confirms the excellent prognosis of pediatric ovarian IT, arguing for conservative surgical approach in GP and against systematic adjuvant chemotherapy, even in ruptured tumors.