Fertility Preservation for Young People with Cancer: What Are the Remaining Challenges?

Abstract

Childhood cancer is rare, with an incidence of around 110 cases per million children per year. Current data suggest that around 80% of children with cancer will be alive five years from diagnosis. Infertility is a major concern for young people who have been treated for cancer. I would strongly recommend that a formal assessment for fertility preservation is undertaken before treatment commences in all young people with cancer (Wallace et al, 2012). All male patients who are able to produce semen should have the opportunity of sperm banking before their treatment starts but is not universally practised, and there are very few “adolescent-friendly” facilities. Discussions must be dealt with sensitively, and using appropriate language which the patient understands. However, many patients and their families derive benefit from open discussion regarding fertility, particularly as this places emphasis on the future and provides reassurance that curative treatment is the aim. Female fertility preservation provides significantly different challenges to that for the male. Embryo freezing is now an accepted and well-established procedure in many centres, but is not available for children who do not have a partner. Cryopreservation using vitrification of mature oocytes has become increasingly successful, but requires the patient to go through a course of hormone stimulation and is therefore not appropriate for children and young girls. Ovarian tissue cryopreservation has the potential advantages of preservation of a large number of oocytes within primordial follicles, it does not require hormonal stimulation when time is short, and is appropriate for the pre-pubertal girl. Disadvantages include the need for an invasive procedure, and the uncertain risk of ovarian contamination in haematological and other malignancies. In vitro growth and maturation of immature oocytes is likely to be possible in the future. Radiotherapy causes both ovarian and uterine damage. Exposure of the pelvis in young girls to radiation is associated with an increased risk of miscarriage, mid-trimester pregnancy loss, preterm birth and low birth weight. In addition to the many scientific and technical issues to be overcome before clinical application of these techniques, a number of ethical and legal issues must also be addressed to ensure a safe and realistic prospect for future fertility in these patients.