Fertility preservation in borderline ovarian tumor patients and survivors

Borderline ovarian tumors (BOTs) represent around 15% of all epithelial ovarian cancer. Around one third of those patients is under 40 and has not completed childbearing when the tumor is diagnosed. Cancer survivors are more and more concerned about their future fertility since a large proportion of those with BOTs are young. Whatever the tumor stage, information regarding future fertility after treatment and fertility preservation (FP) options must be delivered to all patients before treatment. A multidisciplinary team will discuss and propose personalized treatment and FP strategies. Nowadays, the FP options offered to patients with BOT are the followings: i) minimal invasive conservative surgery, ii) oocyte cryopreservation after controlled ovarian stimulation (COS) or in vitro maturation (IVM) and iii) ovarian tissue cryopreservation. Generally, the most common strategy to preserve future fertility is represented by minimal invasive conservative surgery. However, with the remarkable success and evolution of assisted reproductive technologies (ART) - notably progress and efficiency in COS and oocyte vitrification - have led to offer another potential approach for FP consisting in oocyte cryopreservation. Several COS protocols, such as random start or dual stimulation associating tamoxifen or aromatase inhibitors with gonadotropins provide similar results when compared to standard protocols while providing safety by minimizing the risk of high estrogen exposure. When COS is contraindicated, oocyte cryopreservation can still be possible throw IVM. Even though, oocyte competence after IVM is lower than that obtained after COS. A less used approach is cryopreservation of ovarian tissue, consisting in freezing ovarian cortex fragments for a future thawing and graft. Some concerns and limitations regard the ovarian cortex graft and the risk of reintroducing malignant cells once performed. Nonetheless, the latter it is the only option in prepubertal patients.