Non-epithelial Ovarian Cancer: Elucidating Uncommon Gynaecological Malignancies

Non-epithelial ovarian cancers (NEOC) are a group of fascinating but uncommon malignancies which can be extremely challenging to treat. Collectively, these tumours only represent 10-15% of all ovarian cancers and occur in all age groups from childhood to old age. This broad term includes diverse tumours of germ cell origin, sex cord-stromal cell origin, as well as extremely rare types of ovarian cancer, such as small-cell carcinomas and sarcomas, each of which require specialist management. It is imperative that these rare tumours are managed with accurate diagnosis, staging and treatment in order to optimize patient outcomes. The aetiology and molecular origins of each sub-group of NEOC remain poorly understood and international cooperation to facilitate high quality translational research is needed. This review summarizes the published literature on the incidence, clinical presentation, pathology, therapeutic interventions, survival and prognostic factors of each sub-type of NEOC.