I-25: Gamete Cryopreservation for Cancer Patients,Ethical Considerations

Cancer patients often receive gonadotoxic treatments, such as radiation or certain chemotherapies. The doses and regimens used for treatment vary in different individuals and cancers. Recent progress has improved the survival rates of patients with cancer, often using highly aggressive therapies and combinations. This results in growing numbers of cancer survivors, some of whom will be sterile or have compromised fertility. For men, storage of sperm before cancer treatment starts should be routine. Sperm storage is safe and effective. The illness, or an underlying deficit, can result in suboptimal sperm quality, however, modern fertility treatments, such as ICSI, can overcome most sperm deficits. Sperm freezing is not feasible for azoospermic men, or pre-pubertal boys. Methods of storing stem cell stages with potential to develop into sperm are not yet available clinically. For women, oocyte storage is more difficult. Few oocytes are available, ovarian stimulation is required which might exacerbate estrogen-receptor positive breast cancer,ovarian stimulation is timed according to the menstrual cycle which could delay starting cancer treatment, and the pregnancy rates using frozen oocytes are low in many centres (but increasing with vitrification). An alternative for women is ovarian cortex freezing. This is storage of immature, primordial follicles in pieces of the peripheral ovarian tissue, removed by surgery. The tissue can be thawed and transplanted back, allowing the follicles to grow in vivo when the patient wants a pregnancy. In future, growth of follicles might be achieved in vitro to perform IVF, eliminating risks of reintroducing cancer cells in the transplanted tissue. Only ~20 pregnancies have arisen from ovarian cortex freezing, so this is still a research procedure.Ethical considerations: Many issues are raised by both the storage of gametes, and their application in cancer patients. 1. Who should be offered fertility preservation? Should there be age limits or other eligibility criteria? Currently this decision relies upon the cancer clinician who may or may not refer the patient for fertility preservation. 2. To what extent should preparations for life after cancer affect the treatment itself? Are delays acceptable for fertility preservation if they may affect the patient’s survival chances? Who should take this decision? 3. Storage of gametes separates them from the person. Decisions about the stored gametes in the event of incapacity or death need to be made in advance. Accidents and incidents can result in loss of stored material. For how long should gametes be kept? 4. These decisions affect others who have an interest in the patient’s fertility, such as partners, parents and family members. Should these people be able to influence the decisions or the use of stored gametes? For example, should partners have access to the gametes if the cancer patient dies? Should children be born from gametes of the deceased? 5. Is the welfare of the potential child affected? When the patients want to use the stored material, are they really cured? 5 year survival is a widely used survival index for cancer patients, but for parenthood a longer period of survival is desirable. How importanThis presentation focuses on ethical considerations of fertility storage and presents original data on the views of cancer clinicians about sperm storage.