RESUMEN
OBJECTIVE: We return a case of ovarian immature teratoma with peritoneal gliomatose at a woman aged of 20 years. MATERIAL AND METHODS: The diagnosis discovered following pelvic mass increasing volume and treaty by a one-sided annexectomy, with chemotherapy. RESULTS: Eighty-seven cases have been published in the literature. Although potential for recurrence is high, the risk of malignancy is very low. CONCLUSION: Ovarian immature teratoma is a malignant germ cell tumor and represents less than 1% of ovarian malignant tumors. Tissues are derived from the three germ layers (endo-, meso- and ectoderm). Tumor grading is based on the amount of immature neuroepithelium present. The prognosis is directly correlated to histological grade. Rapid (fast) growth leads to large tumors with an early diagnosis. Gliomatosis peritonei is a rare situation, characterized by the recurrence of peritoneal implants after the surgical treatment of ovarian teratoma. This entity does not modify the good prognosis of mature teratomas, but we recommend regular follow-up.