Breast cancer treatment and ovarian function

The aim of this study was to provide an update on ovarian function and the mechanisms of gonadal damage after exposure to chemotherapy in breast cancer survivors. The alkylating agents are toxic to both primordial and growing follicles. However, anti-metabolite drugs are more likely to destroy preantral and antral follicles. Younger patients are more likely to have a higher ovarian reserve, and therefore, more likely to retain some residual ovarian function after exposure to gonadotoxic regimens. However, there can be significant variability in ovarian reserve among patients of the same age. Furthermore, patients with critically diminished ovarian reserve may continue to menstruate regularly. Therefore age and menstrual status are not reliable indicators of good ovarian reserve and might give a false sense of security and result in an adverse outcome if the patient is consulted without considering more reliable quantitative markers of ovarian reserve (antral follicle count and anti-Müllerian hormone) and fertility preservation is not pursued. In contrast to well-documented ovarian toxicity of older chemotherapy regimens, data for newer taxane-containing protocols have only accumulated in the last decade and data are still very limited regarding the impact of targeted therapies on ovarian function.

Risk of chemotherapy-related amenorrhoea (CRA) in premenopausal women undergoing chemotherapy for early stage breast cancer

PURPOSE

While chemotherapy has improved survival among younger women with breast cancer, it can induce temporary or permanent chemotherapy-related amenorrhoea (CRA), impacting survival benefit, quality of life and, importantly for younger patients, fertility.

METHODS

This single institution retrospective study of 107 premenopausal women with early stage breast cancer who received neoadjuvant or adjuvant combined chemotherapy treatment investigates the association of clinicopathological factors (including age-related, gynaecological and tumour-related variables) with CRA and resumption of menses using generalised linear models for univariable and multivariate analyses.

RESULTS

76% of women developed CRA, of which only 40% resumed menses after treatment. Age at time of treatment and at menarche were significantly associated with CRA incidence, with higher rates linked to older age (≥ 40 years) and later menarche (at ≥ 13 years), in both univariable (P = 0.043 and P = 0.009, respectively) and multivariate (P = 0.010 and P = 0.012, respectively) analyses. Age at time of treatment, age at menarche and use of tamoxifen were significantly associated with resumption of menses (with greater resumption rates linked to younger age (< 40 years old), later menarche (≥ 13 years old) or no tamoxifen use status), in both univariable (P < 0.0001, P = 0.002 and P = 0.039, respectively) and multivariate (P = 0.001, P = 0.011 and P = 0.008, respectively) analyses. Menses resumption rates were also significantly higher (P = 0.015) in women with later cessation of menses (after 3-6 chemotherapy cycles rather than sooner).

CONCLUSIONS

Age at menarche and, specially, at time of treatment are important risk factors for CRA. These variables could aid decision-making for treatment selection and fertility preservation among premenopausal women with early breast cancer.