Breast Cancer Treatment Can Affect Ovaries

Chemotherapy for breast cancer was associated with high rate of ovarian failure

(RxWiki News) Studies have shown that women with breast cancer who are under age 50 get the most benefit from chemotherapy. But these are the same women who wonder if the treatment will leave them unable to have children.

A recent study examined how many women treated for breast cancer had ovarian failure, which is a loss of normal ovarian function that can result in early menopause and infertility.

Nearly all women stopped having menstrual periods during chemotherapy for breast cancer, but some regained ovarian function at some point later.

"Talk to your oncologist about your chemotherapy risks and benefits."

This study was conducted by V. Tiong, from the Department of Surgery at University Malaya in Kuala Lumpur, Malaysia, and a team of researchers.

These researchers looked at two groups of women with an average age of 43.

One group consisted of 33 premenopausal women who were receiving chemotherapy for breast cancer. The researchers noted these women’s menstrual history and cancer treatment. They also measured hormone levels in the blood to measure ovarian function.

The other group of 69 women was identified by reviewing medical records for women with breast cancer. This group was contacted and asked about their menstrual history.

Out of six cycles of chemotherapy, 68 percent of women had no menstrual periods after their second cycle of chemotherapy, and 76 percent had no periods after their third cycle of chemotherapy. By the end of chemotherapy treatment, menstrual periods stopped in over 93 percent of the women in the study.

Decreased estradiol levels and increasing FSH levels — two hormones — indicated that the women’s ovarian function was decreasing after the second cycle of chemotherapy. These hormone levels were similar to what is seen in women approaching menopause.

Of the 93 percent of women whose periods stopped, a quarter of them regained their menstrual cycles after an average of about eight months.

The loss of menstrual periods was not associated with the type of chemotherapy or stage of disease, but it was associated with age. Increasing age increased risk of loss of ovarian function.

The authors of this study noted that it was not possible to tell if loss of menses (menstrual period) was due to chemotherapy or if chemotherapy sped up the process. They also remarked that certain types of breast cancer medications, such as tamoxifen (brand name Nolvadex) might have influenced ovarian hormone levels.

“The results of this study will have practical clinical implications for the decision-making process and on the counseling of premenopausal breast cancer patients regarding the possible outcomes and consequences of premature ovarian failure, and will assist in making ‘trade-offs’ between possible benefits of adjuvant [additional] therapy and its side effects,” these authors concluded.

This study was published in the April issue of World Journal of Surgery.

Research grants from the Ministry of Science, Technology and Innovation and the Ministry of Higher Education in Malaysia funded the study.

The research team did not disclose any conflicts of interest.

Review Date: 
April 8, 2014