A case of ovarian growing teratoma syndrome treated by cytoreductive surgery

Ovarian growing teratoma syndrome (GTS) is a rare disease characterized by growth of a benign tumor during or after chemotherapy, following the removal of germ cell gonadal cancers. Although benign, GTS tumors grow gradually and may compress surrounding organs. In addition, up to 3% of GTS cases can undergo malignant transformation. It is, therefore, needed to treat GTS. No standardized management protocol has been established to treat GTS; however, surgical resection is likely the only effective treatment because tumors in GTS are resistant to chemotherapy and radiation therapy. However, complete resection with conventional procedures is sometimes difficult when peritoneal metastasis is widespread. We report a rare case of ovarian GTS with widespread peritoneal metastases, which was totally resected by peritonectomy procedures. A 45-year-old Japanese woman was initially diagnosed with an immature teratoma grade 3, which was treated by hysterectomy and bilateral salpingo-oophorectomy. Adjuvant chemotherapy was performed after surgery with bleomycin, etoposide, cisplatin, and other chemotherapies. Due to recurrence of a chemoresistant tumor and normalization of tumor markers, GTS was suspected. She was referred to our institute, and complete cytoreductive surgery was performed using peritonectomy procedures, including parietal peritoneal resection, greater omentectomy, lesser omentectomy, rectosigmoid colectomy, diaphragm dissection, and cholecystectomy. A complete cytoreduction with no visible residual tumor tissue was achieved.