The observation published in JAMA Surgery that prophylactic contralateral mastectomies are on the rise in men with breast cancer made a lot of news recently, including on major outlets like Newsweek and the Washington Post. The study, by Dr. Ahmedin Jemal of the American Cancer Society and colleagues shows that between 2004/5 and 2010/11 the rate of these prophylactic mastectomies rose from 3% to 5.6% – small numbers, but a large relative increase of 86.7% in 6 years (doi:10.1001/jamasurg.2015.2657). People seem to be wondering why.
By way of a brief background, men make up about 1% of breast cancer patients, and given the relative lack of knowledge about the male form of the disease, they are clinically managed like women with overall good outcomes. Men are typically diagnosed later (older and with more advanced stage) probably because awareness lags behind women and there is of course no screening, but grade for grade we do as well as women. Men can also be predisposed to having breast cancer by BRCA mutations, and are more commonly associated with BRCA2. I’ve written more on the biology of biology of tumor suppressor genes and familial predisposition elsewhere here, and so won’t go into any detail here. Suffice it to say, that as far as we know today, which admittedly isn’t far enough, male breast cancer looks a lot like female breast cancer.
I think it is therefore reasonable to consider whether the reasons why men chose prophylactic contralateral mastectomies are the same that motivate women to make this choice. The report by Jemal and colleagues doesn’t look at BRCA status (data not available) nor does it examine the attitudes that having breast cancer and/or a BRCA mutation inform in people so affected. Excellent work in this latter area is being done by, for example, Dr. Sharlene Hesse-Biber, who has written on women in this context (Waiting for Cancer to Come) and is actively researching men. (Disclosure: I have participated in Dr. Hesse-Biber’s research work as a subject.)
Until we know the full answer of what drives men’s decisions on mastectomy, we can perhaps consider anecdotal evidence: I spoke with a man just last week who made exactly this choice after he learned from the analysis following his first mastectomy, that he was a BRCA2 mutation carrier. His rationale: same as women. He felt that his remaining breast was not useful and it had an elevated risk of growing a tumor, so why not remove it. Why wait for the tumor to grow first?
I think it is therefore most likely that the increase in genetic testing, particularly for BRCA, is driving the increase in men’s prophylactic contralateral mastectomies. For women access to affordable, effective reconstruction is probably a contributing plus, but for men this is not likely, as we rarely opt for this choice.
Are the number out of proportion? In the Huffington Post Dr. Jemal is quoted as saying:
‘[The operation] is only recommended for a small proportion of men,” and the rates observed in the new study are higher than this proportion, said Dr. Ahmedin Jemal, vice president of surveillance and health services research at the American Cancer Society and the lead researcher on the study.’
I am not sure I understand this comment. The proportion of men with breast cancer who likely have a BRCA mutation is likely around 5-10%, although we do not yet have very robust numbers on this, I believe. If true, the percentage of men opting for the prophylactic surgery might correspond quite well with the percentage who have a good genetic reason.
Perhaps Dr. Jemal is arguing that it only makes sense to remove the contralateral breast when the stage of breast cancer is considered curable by surgery alone i.e. at stage I or less. Men admittedly are more often diagnosed at stage II, or even III and IV, and by definition we are talking about men with a diagnosis of cancer and already one mastectomy under (over?) their belt i.e. not people who have a predisposition but no cancer diagnosis, like Ms. Jolie. I understand this biologically: if you are stage II and above the cancer cells are on the move to a greater or lesser extent, and the focus must be on regional control with radiation and systemic control with chemo and hormone therapy, as appropriate. These approaches are aimed at keeping the cells hiding throughout your body at bay. But if we knew where a bunch of likely cells were hiding with a high likelihood, and it was in a very accessible place and in tissue that wasn’t useful, wouldn’t we simply remove them surgically?
Of course the key to this question is data in the form of large cohort studies – ultimately we will want to know whether men with BRCA mutations did better if they had the prophylactic contralateral mastectomies than if they didn’t, both in terms of overall survival and disease free survival. My guess is that it will be a long time before such a study can be done, even retrospectively, in men, so we will look to the women for guidance. Of course over there they haven’t quite agreed on the value of a mammogram yet, so we won’t hold our breath. In the meantime, if it was me (and it isn’t – I do not have BRCA mutations) I would gladly turn the other breast.