Fertility preservation for breast cancer patients.

Breast cancer is the most common neoplasm in women and accounts for 26% (182,460) of all new cancer cases among women. With the use of screening mammography and advancement in other diagnostic modalities, many cases of breast cancer now can be diagnosed and treated at early stages of the disease. Unfortunately, adjuvant chemotherapy regimens commonly used in the treatment of breast cancer may cause premature ovarian failure due to their cytotoxic effects on the germ cells in the ovary. Therefore preservation of fertility in breast cancer survivors at reproductive age has become an important quality of life issue. Fertility preservation is a recently emerged field of reproductive medicine that may help protect the reproductive capability of the cancer survivors and allow them to have children in the future. Embryo freezing is the most established fertility preservation strategy. But conventional ovarian stimulation protocols are contraindicated in breast cancer patients because of the rise of estrogen and its metabolites to supraphysiological levels. Recently developed ovarian stimulation protocols with aromatase inhibitor letrozole and tamoxifen appear to provide a safe stimulation with endogenous estrogen levels comparable with those achieved in the natural cycle. Oocyte freezing can be considered in single women and in those who do not wish donor sperm. Ovarian tissue freezing could also be an option in breast cancer patients who do not wish or have a time for an in vitro fertilization cycle, which requires 10 to 14 days of ovarian stimulation. Thieme Medical Publishers.