New Controversy from Canadian 25 year study of Mammography

The British Journal of Medicine recently published an update on the Canadian Mammography study.

This new study casts doubts on the usefulness of mammograms for preventing breast cancer deaths. For those women who dread the painful and awkward visit to the doctor’s office every year, this comes as great news!  But how is the rest of the medical community welcoming these findings?  Well, with a lot of debate. 

This kind of debate over cancer screening is not new. In fact, it has gone on for years for nearly every type of cancer-screening test. But what is the verdict for mammograms? Do we keep them or boot them?  Before we come to any conclusions, we first need to understand the purpose of a screening test.

An ideal screening test would:

1.       Find cancer early

2.       Prevent death

3.       Not hurt you

4.       Be cheap

5.       Be readily available

6.       Be simple to perform

So how does mammography stack up? Let’s find out!

Do they find cancer early?

Generally speaking, yes. Mammograms can find tumors so small they are undetectable by touch. They can also detect cancer at an early stage before it beings to spread. This, obviously, makes treatment much easier.  So, one point in favor of mammograms.

Do they prevent death?

This is the crux of the debate stemming from this new study. After following 100,000 women in Canada for 25 years, (half had mammograms and half did not), they found that the death rate from breast cancer was nearly identical. This result sure makes mammogram-haters happy.

But of course, mammograms do save lives by detecting cancer early.  The thing is, these new findings suggest that regular breast exams pick up tumors early enough for successful treatment as well.  Also, it appears that treatments have been improving in effectiveness, preventing death in more advanced cases of breast cancer.   

Do mammograms hurt you?

Technically, yes – they could. There are two ways that mammograms may hurt you besides the obvious pain associated with squeezing the breast.

First, doctors worry that the small doses of radiation used in mammograms may actually cause cancer. Second, false positives subject women to needless biopsies and surgery (not to mention stress and financial burden). The Canadian study found that of the 50,000 who had mammograms, roughly 140 of them were falsely diagnosed.

The big question is – do these harms actually outweigh the benefits?  So far, most professionals don’t think so.

Are mammograms cheap?

At a cost of about 100 dollars per exam, it doesn’t sound too expensive. But when you consider that 37 million mammograms are performed in the U.S. each year at a cost of 3.7 billion dollars, the cost seems astronomical!  Could that money be put to better use?  Maybe, maybe not.  

Is it readily available?

There have been great efforts in the U.S. to make mammograms available. Nearly every health care system is equipped with mammography equipment and skilled radiologists to interpret the findings.  Great strides have been made to ensure access for everyone, including low-income patients and the un-insured. 

Are mammograms simple to perform?  

This one is all up to personal opinion.

What is the consensus?

While the debate rages on, The American Cancer Society, The American Board of Surgery, Cancer.org, Mayo Clinic and nearly every large medical group in the U.S. still recommend yearly mammogram screening after age 40. 

However, these organizations are calling for an expert panel to review the new data. There seems to be a number of quality studies that support both sides.  We’ll just have to wait and see how the debate ensues.

So what should women do in the meantime?  Well, better safe than sorry!  Get a mammogram until you hear otherwise.