Ovarian growing teratoma syndrome with multiple metastases in the abdominal cavity and liver: A case report

BACKGROUND Growing teratoma syndrome (GTS) is an unusual presentation of an amazing transformation of teratoma from malignant to benign on pathology during or after systemic or intraperitoneal chemotherapy. The definitive pathogenesis is still not fully understood due to the lack of large-sample studies. CASE SUMMARY A 53-year-old woman underwent radical surgery and postoperative intraperitoneal chemotherapy due to immature teratoma of the right ovary at the age of 28. She remained well during a 25-year follow-up period after surgery. Multiple asymptomatic solid masses were found in the liver on ultrasonography a month ago. Enhanced computed tomography (CT) of the abdomen revealed multiple masses in the abdominal cavity. The largest one was located in the posterior peritoneum next to the sixth segment of the right liver, about 7.9 cm x 7.5 cm in size. Three masses were present inside the liver, and one mass was in the right pelvic floor. Multiple lumps in the abdominal cavity were completely removed by surgery. During the operation, multiple space-occupying lesions were seen, ranging in size from 0.5 to 3 cm, and grayish white in color and hard in texture. Ovarian GTS was finally diagnosed based on postoperative pathology. After surgery, she recovered uneventfully. During a 3-year follow-up, the patient remained free of the disease without any recurrence on CT scan. CONCLUSION GTS is a rare phenomenon characterized by conversion of immature teratoma to mature one during or after chemotherapy and presents as growing and metastasizing masses. The pathogenesis of GTS is unclear, and the prognosis is good after surgical resection.