Risk-reducing mastectomy may lower breast cancer mortality in some women: Study

A new study published in the British Journal of Cancer suggests that risk-reducing mastectomies (RRM) in women with a BRCA1 or BRCA2 genetic variant may significantly reduce the risk of being diagnosed with breast cancer and lower the probability of death.

Women who have an inherited BRCA1 or BRCA2 variant have an 80 per cent risk of developing breast cancer over the course of their lifetime. However, research has shown that an RRM reduces the risk of breast cancer by 90 per cent, according to the study.

Professor Kelly Metcalfe of the Lawrence Bloomberg Faculty of Nursing at the University of Toronto, Canada, stated, “The decision to have a risk-reducing mastectomy is often difficult for a woman to make, and the more evidence we are able to provide them with when they are making that decision, the more informed their care plan will be.” Metcalfe also highlighted that in Canada, 30 per cent of women with a pathogenic variant opt for this surgery.

The study, which followed over 1,600 participants from a registry of women with a pathogenic BRCA 1/2 variant from nine different countries over the course of six years, found that RRM reduced the risk of breast cancer by 80 per cent, and the probability of dying of breast cancer 15 years after risk-reducing mastectomy was less than one per cent.

While there wasn’t a significant difference in deaths between the group who opted for a RRM and the control group in this study, Metcalfe pointed out that following these participants for an extended period would generate more evidence to assess the true mortality risk with precision and highlight the benefits associated with this type of surgery.

Metcalfe also mentioned that there is currently good screening in place for breast cancer, including breast MRI, so surgery is only offered as an option, not a recommendation. However, she noted that with more studies being conducted to assess women’s trajectory and risk factors following RRM, it will provide insight into whether guidelines need to be changed in the future.

This study sheds light on the potential benefits of risk-reducing mastectomies for women with a BRCA1 or BRCA2 genetic variant and adds to the understanding of the impact of this type of surgery on the risk of developing and dying from breast cancer.