Research finds women undergoing fertility preservation procedures are not at increased risk of breast cancer recurrence.
A new study by Karolinska Institutet in Sweden followed participants who were undergoing fertility preservation procedures over a period of five years. The results could provide new hope and safety to women who want to preserve their fertility after chemotherapy treatment for cancer.
Many women opt out of fertility preservation
Around one in ten women diagnosed with breast cancer are of childbearing age and are at risk of becoming infertile after receiving chemotherapy. Many women, therefore, choose to undergo fertility preservation procedures in the hope that they will be able to conceive after completing cancer treatment. Methods of fertility treatment include cryopreservation, the freezing of embryos, female gametes (oocytes), and ovarian tissue.
“It is not unusual that women with hormone-positive breast cancer or their treating doctors opt out of the procedures for fertility preservation because of the fear that these procedures will increase the risk of breast cancer recurrence or death. In some cases, women are also advised to wait five-ten years before trying to conceive, and with increasing age, fecundity in all women decreases,” said Anna Marklund, the study’s lead author and researcher at the Department of Oncology-Pathology, Karolinska Institutet. “More knowledge is therefore needed about the safety of procedures for fertility preservation at the time of a breast cancer diagnosis,” she added.
The study examined data from 1,275 women of childbearing age who were treated for breast cancer between 1994-2017 in Sweden. 245 of these women underwent procedures for fertility preservation, both with and without hormonal stimulation. The other 850 women were treated for breast cancer but did not undergo procedures for to preserve their fertility.
The women who underwent the preservation treatment and those who did not were matched based on age at diagnosis, calendar period at diagnosis, and healthcare region. The data was drawn from both nationwide healthcare registers and population registers and included data on disease and treatment-related variables and socio-economic characteristics.
Low rates of relapse after fertility treatment
The data revealed that 89% of women who underwent hormonal stimulation of the ovaries did not relapse over the five years. It was found that 83% of those who underwent ovarian tissue freezing and 82% who did not undergo any preservation did not relapse.
The survival rate after five years for those who underwent hormonal stimulation to freeze eggs or embryos was 96%. The survival rate was 93% in the group that underwent procedures for preserving fertility and 90% in the group that did not undergo any preservation procedures.
“We did not see any increased risk of relapse or mortality when procedures for fertility preservation were undertaken, compared to the women who did not undergo procedures for fertility preservation. This is valuable information that can contribute to changed care routines when it comes to young women with breast cancer who want to preserve their fertility,” said Marklund.