Imaging Appearance of Nongerminoma Pediatric Ovarian Germ Cell Tumors Does Not Discriminate Benign from Malignant Histology

Study Objective Pediatric ovarian neoplasms with imaging appearance suggestive of teratoma are often presumed to have low risk of malignancy. We assessed the pre-operative imaging appearance of pediatric malignant ovarian germ cell tumors (MOGCT) and the presence of associated teratoma in a series of MOGCT. Design Retrospective review of clinical and pathology data. Setting Multicenter trial for extracranial malignant germ cell tumors in young female individuals by the Children's Oncology Group (COG study AGCT0132) that included yolk sac tumor, embryonal carcinoma and choriocarcinoma. Participants Female individuals 0-20 years of age at enrollment with ovarian primary nonseminomatous malignant germ cell tumors. Interventions Review of data forms, including prospectively collected surgical checklist documenting imaging characteristics of the tumor, and review of pathology reports. Main Outcome Measures Description of imaging appearance and frequency of mixed histology with benign teratoma elements. Results A total of 138 female individuals (11 months to 20 years of age) had primary ovarian tumors. Imaging appearance and pathology information were available for 133 patients. Among the 133 patients, tumor appearance was solid (10.5%), solid with calcification (3.0%), mixed cystic and solid (58.7%), mixed cystic and solid with calcification (24.8%), and unknown (3.0%). In all, 54% had elements of teratoma in addition to malignant histology. Conclusion Mixed cystic and solid appearance with or without calcification was seen in 83.5% of pediatric ovarian malignant germ cell tumors. Associated benign teratoma was common. The presence of a mixed cystic and solid appearance on preoperative imaging should not dissuade the surgeon from obtaining preoperative serum markers and undertaking complete surgical staging.