Laparoscopic and imaging findings of growing teratoma syndrome Salih Taşkın, Batuhan Turgay, Yavuz Emre Şükür, Fırat Ortaç Abstract Department of Obstetrics and Gynecology, Ankara University Faculty of Medicine, Ankara, Turkey Growing teratoma syndrome (GTS) occurs during post-treatment observation of ovarian malignant germ cell tumors. The characteristic features of this syndrome are normal tumor marker levels and evident tumoral mass or implants on imaging studies. We report a case of GTS in a 22-year- old woman with a malignant germ cell tumor. After staging surgery and chemotherapy, computed tomography showed peritoneal implants. Laparoscopy was planned to exclude malignant recurrence. During laparoscopy, smooth and pink-colored lesions were seen at the lateral pelvic wall. Histopathologic evaluation reported mature teratoma tissue with extensive mature glial components. GTS is not a malignant condition and the benefit of radical surgical intervention in cases without mass-related complication is not proven. GTS should be kept in mind after primary treatment of ovarian immature teratoma. Keywords: Growing teratoma syndrome, laparoscopy, management Video Article 158 Introduction A 19 year-old nulli-gravid woman with massive ascites and abdominal mass was referred to our clinic. Laboratory examination revealed elevated tumor markers (AFP: 922.4 ng/mL, CA 125=331 U/mL, CA 19-9=418.1 U/mL). Computed tomography (CT) revealed a huge mass filling the abdomen and a large volume of ascites (Figure 1). Midline laparotomy was performed due to the pre-diagnosis of ovarian malignant germ cell tumor. During the intraoperative observation, a huge left- side ovarian mass and massive peritoneal-omental implants were detected. Subsequently, left salphingo-oophorectomy, total omentectomy, peritonectomy, and bilateral pelvic and para-aortic lymph node dissection were performed. There was no residual tumor at the end of the surgery. Final pathology was stage IIIC immature teratoma with retroperitoneal lymph node involvement. Four cycles of bleomycine-etoposide-paclitaxel chemotherapy was administered. At the end of the treatment tumor markers were within normal range. Two months after chemotherapy and six months after the operation, during a routine follow-up visit, CT examination revealed peritoneal implants. Tumor markers remained within normal ranges and the patient was asymptomatic. Recurrence of malignant germ cell tumor was not expected and so Received: 21 February, 2019 Accepted: 27 April, 2020 Address for Correspondence: Batuhan Turgay e.mail: batuhanturgay@hotmail.com ORCID: orcid.org/0000-0001-9927-181X © Copyright 2021 by the Turkish-German Gynecological Education and Research Foundation - Available online at www.jtgga.org Journal of the Turkish-German Gynecological Association published by Galenos Publishing House. DOI: 10.4274/jtgga.galenos.2020.2019.0034 Taşkın et al. Growing teratoma syndrome J Turk Ger Gynecol Assoc 2021; 22: 158-60 Figure 1. Preoperative computerized tomography image of the abdominal mass