Ovarian function and childbearing issues in breast cancer survivors

The increasing number of breast cancer survivors makes the issues of ovarian dysfunction and childbearing ability more and more relevant for the quality of life of these patients. The incidence of ovarian dysfunction is related to patient age, the specific agents used and the total dose administered, especially the dose of alkylating agents such as cyclophosphamide. Amenorrhea rates following combination chemotherapy consisting of cyclophosphamide + methotrexate + 5-flurouracil (CMF regimen) range from 21 to 71% in women aged 40 years and younger, and from 40 to 100% in older ones. In most series anthracycline-based adjuvant chemotherapy regimens appear to have a lower incidence of amenorrhea, which is probably due to the lower cumulative cyclophosphamide dose administered compared with that given in the CMF regimen. Few data are currently available regarding ovarian function in women treated with taxane-based chemotherapy. In a recent retrospective study on 191 patients, the amenorrhea rate was 64% for women who received doxorubicin + cyclophosphamide (AC regimen) followed by a taxane, compared with 55% (p = 0.05) for those treated with AC alone. Forty percent of women aged 40 years or younger resumed menstruation, whereas the amenorrhea was more likely to be irreversible in older women; however, the addition of a taxane did not change the reversibility rate. Ovarian reserve can be tested with serum assays of follicle-stimulating hormone, inhibin B, estradiol and anti-Müllerian hormone, as well as by ultrasound assessment of antral follicle count. A review of literature data failed to show that a subsequent pregnancy increases the risk of recurrence and death in breast cancer survivors, and some series have even detected longer survival for patients who get pregnant after breast cancer treatment. This apparent survival benefit, probably due to a selection bias called the 'healthy mother effect', suggests that breast cancer survivors who subsequently conceive are a self-selecting group of women with better prognosis. The little available information appears to show no increase in the incidence of prematurity, stillbirth or congenital malformations in their babies. In conclusion, future pregnancy is a viable option for a woman treated for early-stage breast cancer and does not appear to be detrimental to either the mother or her offspring.