A Basic Fact About Breasts That Could Save Your Life: And The Forces Trying to Keep it Under Wraps

Important information about breasts has been kept from women, increasing the risk of undetected cancer.

One in eight. That’s how many women will be diagnosed with breast cancer in her lifetime, according to the National Cancer Institute (NCI). This grim statistic lands in the spotlight during Breast Cancer Awareness Month, which is currently underway.  

But, for all of the awareness raised about breast cancer over the years, there’s a certain term that is largely left out of the lexicon surrounding breast cancer,the most common cancer in women. It’s a term Connecticut resident and cancer survivor Nancy Cappello has spent nearly a decade fighting to retrieve from the shadows and inject into the conversation. This term is “breast density.”

“If you look in the news this October, it’ll be pink, pink, pink for Breast Cancer Awareness month,” says Cappello. “I call it breast density unawareness—many women still do not know of breast density, or if they’ve heard of it, they don’t know what it really means to them.”

Breast density refers to the ratio of tissue to fat in a woman’s breast. A dense breast has more fibroglandular tissue and less fat. Forty percent of women have dense tissue, according to the American College of Radiology Imaging Network (ACRIN), which is significant because these women are five times more likely to develop breast cancer. They’re also less likely to have it detected on a mammogram.

A January 2011 Mayo Clinic study found that mammograms fail to find 75 percent of cancer in women with dense breast tissue. The primary cause of “false-negative results” in mammograms is high breast density, according to the NCI.

However, until recently, it was standard practice nationwide for doctors to keep information about breast density from patients, and as a result many people with dense breasts do not have cancer detected until it is well developed.

While breast density—and the ineffectiveness of mammograms on dense breasts—is not new, in recent years a battle has arisen to bring unprecedented attention to the issue. As a result the standard practice of keeping breast density knowledge a secret from women has begun to change, but not without a surprising amount of opposition. On the frontlines of resistance is the American College of Radiology (ACR), the nation’s principal association of radiology professionals, an organization that benefits financially from mammograms.

The Status Quo

When Cappello was diagnosed with stage-three breast cancer in early 2004, she was baffled. Less than three months earlier, she’d received normal results on her mammogram, just as she always had from her annual screenings, which she was diligent about. Her doctor found a lump during a standard manual exam that turned out to be cancer that had spread to 13 lymph nodes and most likely been developing for years. 

“What do you mean I have breast cancer?” she recalls asking her doctor. “What happened? I just got a mammogram that says ‘we are pleased to tell you that your results are normal.’”

The answer she was given perplexed her further. She was told that she had dense breasts, and that dense tissue shows up as white on a mammogram and can “mask,” or obscure, cancer, which also appears as white. (Santa Barbara radiologist Judy Dean has said it has been compared to trying to find a snowball in a blizzard.) Why, Cappello demanded, hadn’t she heard of breast density, or been told that she was affected by it?

Simply put, most doctors do not share this information with women. Ninety-five percent of women don’t know their breast tissue density, and less than one in 10 doctors inform their patients of their density, according to a May 2010 survey conducted by Harris Interactive.