Cryopreservation of in vitro matured oocytes after ex vivo oocyte retrieval from gynecologic cancer patients undergoing radical surgery

Abstract

Objective: The aim of this study was to report a case series of in vitro matured (IVM) oocyte freezing in gynecologic cancer patients undergoingradical surgery under time constraints as an option for fertility preservation (FP).Methods: Case series report. University-based in vitro fertilization center. Six gynecologic cancer patients who were scheduled to undergo radicalsurgery the next day were referred for FP. The patients had endometrial (n=2), ovarian (n=3), and double primary endometrial and ovarian(n=1) cancer. Ex vivo retrieval of immature oocytes from macroscopically normal ovarian tissue was followed by mature oocyte freezing afterIVM or embryo freezing with intracytoplasmic sperm injection.Results: A total of 53 oocytes were retrieved from five patients, with a mean of 10.6 oocytes per patient. After IVM, a total of 36 mature oocyteswere obtained, demonstrating a 67.9% maturation rate. With regard to the ovarian cancer patients, seven IVM oocytes were frozen from patient3, who had stage IC cancer, whereas one IVM oocyte was frozen from patient 4, who had stage IV cancer despite being of a similar age.With regard to the endometrial cancer patients, 15 IVM oocytes from patient 1 were frozen. Five embryos were frozen after the fertilization ofIVM oocytes from patient 6.Conclusion: Immature oocytes can be successfully retrieved ex vivo from macroscopically normal ovarian tissue before radical surgery. IVM oocytefreezing provides a possible FP option in patients with advanced-stage endometrial or ovarian cancer without the risk of cancer cell spillageor time delays.