Bilateral mastectomy has become a common procedure to treat and to prevent breast cancer. The rate of bilateral mastectomy is increasing in the United States, in the United Kingdom, and also in Singapore among women with high grade and high risk of breast cancer^1–3.

An observational study published this month on The Journal of American Medical Association⁴ compared the use and the mortality rate of bilateral mastectomy, unilateral mastectomy, and breast conserving surgery in 189,734 women diagnosed with stage 0–III breast cancer in California between 1998 and 2011. The team from the Cancer Prevention Institute of California and Stanford University found that bilateral mastectomy had an annual increase of 14.3% (from 2.0 % in 1998 to 12.3% in 2011), and it was more common among younger, white non-Hispanic women, with bigger and  higher grade tumors, higher education, and a private insurance. On the other hand, unilateral mastectomy was more diffuse in women older than 64 years, of Asian, Hispanic, and American Indian ethnicity, with large tumor size, high grade, and no private insurance. Compared with bilateral mastectomy, unilateral mastectomy was associated with 30% increased all-cause mortality; instead, there was no difference in mortality rate between bilateral mastectomy and breast-conserving surgery. Comparing all three procedures in early stage breast cancer patients, there was no benefit on survival associated with bilateral mastectomy over breast-conserving surgery; higher mortality was only associated with unilateral mastectomy.

This is the first study presenting a comparison among the three procedures. Other studies were published in the past comparing only two procedures at a time, but never all three together. The authors of this study state that maybe the use of bilateral mastectomy could be reduced, because there are no elements to support its benefits over other, less invasive treatments, such as breast-conserving surgery. This study was performed to identify whether the rise in bilateral mastectomies could be somehow justified, or whether the procedure could be substituted with a less expensive one. Bilateral mastectomy is an expensive procedure, and in a private healthcare system clinicians need to present supportive data to justify the selection of a procedure over another one.

If there are not enough data supporting this rise, the increase might have been caused by excessive precaution or fear. Whether it was fear or something else, patients have the right to know the real risks and benefits of each treatment based on actual data, because they are going to make the last decision, not the clinicians or the health policy makers.

 

1. Trends in the use of bilateral mastectomy in England from 2002 to 2011: retrospective analysis of hospital episode statistics. Neuburger J, Macneill F, Jeevan R, van der Meulen JH, Cromwell DA. BMJ Open. 2013 Aug 1;3(8). pii: e003179. doi: 10.1136/bmjopen-2013-003179.
2. Contralateral prophylactic mastectomy in an Asian population: a single institution review. Sim Y, Tan VK, Ho GH, Wong CY, Madhukumar P, Tan BK, Yong WS, Ng YY, Ong KW. Breast. 2014 Feb;23(1):56-62. doi: 10.1016/j.breast.2013.10.008. Epub 2013 Nov 23.
3. Contralateral prophylactic mastectomy in women with breast cancer: trends, predictors, and areas for future research. Tracy MS, Rosenberg SM, Dominici L, Partridge AH. Breast Cancer Res Treat. 2013 Aug;140(3):447-52. doi: 10.1007/s10549-013-2643-6. Epub 2013 Jul 28. Review.
4. Use of and mortality after bilateral mastectomy compared with other surgical treatments for breast cancer in California, 1998-2011. Kurian AW, Lichtensztajn DY, Keegan TH, Nelson DO, Clarke CA, SL. JAMA. 2014 Sep 3, 312(9):902-14. doi: 10.1001/jama.2014.10707.