The classification of ovarian germ cell tumours has remained unchanged for many years, while there have been considerable changes in the testicular classification. In recent years there has been concern about the overtreatment of clinical stage 1 testicular germ cell tumours with increasing use of surveillance for low-risk disease. We outline here the current classification of germ cell tumours of the ovary with particular regard to treatment and outcome and highlight some areas which may cause confusion, particularly pertaining to immature teratomas and mixed germ cell tumours. We suggest that some minor changes to the classification, evidenced by a recent retrospective series by some of the authors, may lead to less adjuvant chemotherapy for immature teratomas and may obviate the need for the grading of immature teratomas, by aligning with testicular experience in pure post-pubertal teratomas. Adoption of this will require retrospective and prospective re-evaluation, but may avoid long-term patient morbidity.
Keywords: Immature teratoma; dysgerminoma; germ cell tumour; neuroepithelium; ovary.
© 2019 John Wiley & Sons Ltd.