Ovarian tissue cryopreservation and gynecologic oncology: a review

Sperm cryopreservation permits young men, undergoing cancer treatments, to preserve their fertility. Ovarian tissue cryopreservation have the same goal for young women and could also be an option for children. However, only primordial follicles survive after freezing and a follicular maturation is needed after thawing. This maturation has not yet been realized in humans, pregnancies have only been obtained in animal models. As cryopreservation is yet effective in humans, many teams have already cryopreserved the ovarian tissue of patients who have nothing to lose as their follicular reserve would have been destroyed or severely depleted by cancer treatment. The preservation of fertility is rarely an issue in gynecologic oncology because it usually concerns post-menopausal women. However, they are early-onset forms of gynecologic cancers and in these cases fertility is often threatened. Ovarian tissue cryopreservation may be performed when curative or prophylactic ovariectomy must be undergone, when chemotherapy with high-dose alkylating agents is planned or when pelvic radiation is needed (particularly in cases requiring chemotherapy combined with radiotherapy). In some of these situations it would be dangerous to graft back the tissue to the patient as cancer cells could remain within the grafts, the best solution in this case would be the in vitro follicular maturation.