Female Oncofertility: Current Understandings, Therapeutic Approaches, Controversies, and Future Perspectives

Abstract

Recent advances in early detection and oncological therapies have ameliorated the survival rate of young cancer patients. Yet, ovarian impairment induced by chemotherapy and radiotherapy is still a challenging issue. This review, based on clinical and lab-based studies, summarizes the evidence of gonadotoxicity of chemoradiotherapy, the recent approaches, ongoing controversies, and future perspectives of fertility preservation (FP) in female patients who have experienced chemo- or radio-therapy. Existing data indicate that chemotherapeutic agents induce DNA alterations and massive follicle activation via the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway. Meanwhile, the radiation causes ionizing damage, leading to germ cell loss. In addition to the well-established methods, numerous therapeutic approaches have been suggested, including minimizing the follicle loss in cryopreserved ovarian grafts after transplantation, in vitro activation or in vitro growing of follicles, artificial ovarian development, or fertoprotective adjuvant to prevent ovarian damage from chemotherapy. Some reports have revealed positive outcomes from these therapies, whereas others have demonstrated conflictions. Future perspectives are improving the live birth rate of FP, especially in patients with adverse ovarian reserve, eliminating the risk of malignancy reintroducing, and increasing society's awareness of FP importance.

Keywords: chemotherapy; fertility preservation; gonadotoxic; oncofertility; oocyte quality; ovarian reserve; premature ovarian insufficiency; radiotherapy.

Figure 1

Three mechanisms of chemo- and radio-therapy-induced follicular quantity depletion: enhancement of apoptosis, accelerated activation of PFs. (A) DNA alterations induced by chemotherapeutic agents and radiation activates TAp53 protein, leading to the apoptosis. (B) Chemotherapeutic agents activate the phosphoinositide 3-kinase (PI3K)/Akt/forkhead box protein O3a (FOXO3a), which in turn induce the activation of PFs, resulting in the extensive loss of PFs. (C) Chemotherapeutic agents impair the epithelial tissue of vessels in the ovary, resulting in a reduction in the vascularization.