What recent primary studies tell us about ovarian teratomas in children: a scoping review

Our knowledge of ovarian teratomas in children is still far from complete, and much remains to be discovered. Here, we conduct a scoping review of the primary research related to ovarian teratomas in pediatric age. To our knowledge, there is no published synthesis of the literature surrounding ovarian teratomas in children using scoping review methodology. We identified 24 studies from 11 countries; 18 studies were retrospective, 3 were prospective, and 3 were experimental. There were 6 studies concerning mature teratomas, 5 concerning immature teratomas, and 13 that included both tumor types. Overall, 9 out of all the studies concerned more than 50 patients. We revealed 7 major branches of research within the topic of ovarian teratoma in pediatric population: recurrence rate/relapse and follow-up strategy, malignant potential, prognostic factors, use of sparing surgery, differences between the use of laparoscopy and laparotomy, use of chemotherapy, and additional examinations to test the character of the lesion (immature vs. mature). This scoping review has revealed a number of knowledge gaps in the evidence base for pediatric ovarian teratomas. Overall, this topic has not been extensively explored, and more research dedicated exclusively to this tumor and patient population is required. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s10555-020-09844-3) contains supplementary material, which is available to authorized users.