Ovarian tissue cryopreservation and transplantation: preliminary findings and implications for cancer patients.
Cancer treatment modalities are increasingly more effective in achieving complete remission and cure. Aggressive chemotherapy and radiotherapy, as well as bone marrow transplantation, results in >90% cure in many cancers of children and young women. As a result of this success however, a new problem has arisen. Many young women survive to live the rest of their lives in menopause, and have no chance of conceiving on their own. Oocyte cryopreservation has resulted in a handful of pregnancies, but the technique may not be applicable to young women and children. Ovarian tissue cryopreservation and transplantation has emerged against this background, first in successful rodent studies, and then in sheep and human ovarian xenograft studies. Because of the encouraging results with animals and xenografts, a human ovarian transplantation trial was launched. Pelvic auto-transplantation of frozen-banked ovarian tissue resulted in ovulation in one patient. Several other patients received fresh grafts subcutaneously, and preliminary results indicated antral follicle development at least in one patient. With the addition of promising data from humans, ovarian tissue cryopreservation from selected patients before cancer treatment, and in those requiring oophorectomy for benign causes, is now advocated.