Last week, the esteemed Cochrane Collaboration, an international organization that evaluates medical research, released a new analysis of the large controlled studies that have looked at whether breast self-exam saves lives.
Their conclusion: â€œData from two large trials do not suggest a beneficial effect of screening by breast self-examination but do suggest increased harm in terms of increased numbers of benign lesions identified and an increased number of biopsies performed. At present, screening by breast self-examination or physical examination cannot be recommended.â€
Not surprisingly, the media were all over their new report. And as I read these news stories, and my quotes in them, I was frequently struck both by how many reporters got aspects of the story wrong and by what readers took away from the story, as evidenced by the calls we received and comments logged on media websites.
First of all, this was not a new study. It was a new analysis of the large research studies that have been done on this topic. Secondly, this is not a â€œnewâ€ finding. The Cochrane Collaboration published a research review of breast self-exam (BSE) in 2003 that came to the same conclusion. In fact, it was this review that led the American Cancer Society to update its own BSE recommendations and to call the exam optional.
The new Cochrane review assessed findings from two large population-based trials in Russia and Shanghai. In both studies, the researchers divided the women into two groups. One group was taught BSE. The other was not. The researchers followed both groups of women for about 10 years. The end result: There was no statistically significant difference in breast cancer mortality between the two groups.
The best study, led by Dr. David Thomas at the Fred Hutchinson Cancer Research Center, was based in China, where women did not have routine access to mammography screening. In this study, one group of 133,000 women underwent intensive instruction in formal BSE. They also received two refresher courses. The second group of 133,000 women had no instruction in BSE. After 10 years, the researchers found there was no difference in deaths from cancers, size of tumors, or cancer stage at diagnosis between the two groups. The only difference was that the group doing formal BSE has more benign biopsies.
While this seems counterintuitive, the problem is mostly semantic. When a woman finds a cancer herself, she refers to that as BSE. When a researcher does a study they are talking about formal breast self exam, the kind that is shown on the videos and takes twenty minutesâ€¦the kind that most of us donâ€™t do. The women in the control group in the China study also found their own cancers, they just were not doing formal BSE.
What this means is that formal BSE is not better than the normal poking around that we all do.
So the answer is not to stop women from touching their breasts or to report any changes they might find to their doctorsâ€”although it appears that is what many women seemed to think the media were reporting. Rather, it means that women do not have to go on a search and destroy mission every month, and that they should not feel guilty if they do not do formal BSE. Thatâ€™s because the research shows that the normal poking around and casual touching that women do of their breasts, or the touching that their partners may do during sex, is as likely to find a cancerous lump as is BSE.
I think this finding angered so many women because women have been taught for years that BSE is something that they can do to â€œpreventâ€™ breast cancer. But BSE was never breast cancer â€œprevention.â€ By the time you can feel a lump, itâ€™s been there for some time.
We had hoped that BSE would find cancers early before they spread. This idea made sense when we believed that all breast cancers grew slowly until they reached a certain point and started to spread. But the new data suggests that there are many different kinds of breast cancer based on their DNA mutations, some of which grow very slowly and some of which grow quite fast. If you have a very fast growing and fast spreading one, mammography and BSE and physician exam will not make a difference. They also donâ€™t make much of a difference if you have a slow-growing tumor that may never spread. Itâ€™s the middle group where mammography may have its biggest impact.
Itâ€™s hard to let go of things we hold onto, especially something like BSE. We all know women who swear by it, who say that it was BSE that saved their lives. But as we learn more about cancer, and as we look at the research on BSE, we need to use this as an opportunity to examine what weâ€™ve been taught about breast cancer and early detection.
What this review really points to is the need for breast cancer research to shift its focus from early detection to finding the cause of breast cancer and how to prevent it. Thatâ€™s the only way were going to truly be able to make a difference in this disease.