Murat Sönmezer

Abstract Learning Objectives After completing this course, the reader will be able to: Explain how chemotherapy for breast cancer impacts ovarian function.Discuss the incidence of ovarian failure after chemotherapy and list the chemotherapeutic agents most likely to cause loss of fertility in breast cancer patients.Describe options for fertility preservation in women undergoing breast cancer therapy. Access and take the CME test online and receive 1 AMA PRA category 1 credit at CME.TheOncologist.com Breast cancer accounts for one third of all neoplasms seen in reproductive-age women and affects tens of thousands of women each year in that age group. The adjuvant chemotherapy regimens used for the treatment commonly affect fertility and cause premature ovarian failure. There have been recent advances in the field of fertility preservation, which can allow many of these breast cancer survivors to have children in the future. The most established option is embryo cryopreservation; oocyte cryopreservation can be considered in single women. Both of these approaches require approximately 2 weeks of ovarian stimulation beginning with the onset of the patient's menstrual cycle. Thus, it is crucial that these patients are referred to appropriate assisted reproduction centers as soon as they are diagnosed with breast cancer. Recently developed ovarian stimulation protocols using tamoxifen and letrozole can be used to increase the margin of safety in these patients. When and if a breast cancer patient does not have time to undergo ovarian stimulation prior to chemotherapy, ovarian cryopreservation for future autotransplantation can be offered as the last resort. The benefit of ovarian protection by gonadotropin-releasing hormone analogues is unproven and unlikely, and thus this treatment should not be offered as the sole method of fertility preservation.

Every year, an increasing number of women with malignant and nonmalignant diseases is successfully treated with cytotoxic chemotherapy and/or radiotherapy. Many of these patients suffer from infertility and gonadal failure as a result of these treatments. At present, these patients may resort to assisted-reproduction techniques to protect their future childbearing potential before the implementation of cytotoxic therapy. While embryo cryopreservation is an established technology, oocyte and ovarian tissue freezing techniques are still investigational. Nevertheless both of these techniques have resulted in live births. Apart from assisted-reproduction techniques, it has been extensively debated whether administration of gonadotropin-releasing hormone (GnRH) analogues in conjunction with chemotherapy can protect ovarian reserve against cytotoxic insult. In this manuscript, we debate the rationale for the effectiveness of GnRH analogue coadministration in preservation of fertility by reviewing the literature, and provide preliminary data to support our views.