IE 11 is not supported. For an optimal experience visit our site on another browser.

The problem with mammograms

NBC’s chief science correspondent Robert Bazell reports on the importance of an early diagnosis when detecting breast cancer — by getting the technique that is right for you.
/ Source: NBC News

By now we’ve all heard about the importance of an early diagnosis when detecting breast cancer — but which technique is right for you? NBC’s chief science correspondent Robert Bazell fills us in on the latest.

Frances Blassberg had cancer in one breast that was missed by mammogram. “The lump, even after it was felt by myself and by the surgeon, was never detected on mammography.”

Doctors located the cancer with a sonogram — a tool that uses sound waves. Blassberg also had cancer in her other breast.

“The other cancers in the other breast never showed up on either a mammogram or a sonogram.”

Magnetic Resonance Imaging — often called MRI — found the second cancer, and Blassberg is fine after treatment. But her case illustrates a big problem.

Much of the efforts in combating breast cancer encourage women to get regular screening mammograms. And it helps. In the last decade the death rate from breast cancer fell 19 per cent — and mammograms certainly played a big role. But, the experts say, mammograms cannot be the only answer.

“Certainly, an expectation that a mammogram is eliminating the problem of breast cancer is completely unrealistic,” says Dr. David Dershaw is director of breast imaging at Memorial Sloan Kettering Cancer Center in New York.

“Mammography, because of the physics involved in what it is that we do, is capable of detecting somewhere between 3/4 and 9/10 of breast cancers that occur. But there are breast cancers — that can not be found on the mammogram,” adds Dershaw.

The proportion that is not found adds up to tens of thousands of cases in the U.S. every year.

There is no question that sonograms can help find some of them — especially in women who have so dense or non-fatty breasts.

“It’s the second most important breast imaging technique that we have at the present time,” says Dershaw.

Doctors and just starting to routinely use MRIs and they will find even more cancers. So why not give both tests routinely to all women?

One reason is cost. Mammograms typically cost about $85. Sonograms are 2 or 3 times that and an MRI is ten times as much. But even more important, MRIs and sonograms often find suspicious areas that look like cancer but are not — false positives. And those have to be investigated with needle biopsies that are often painful.

And as Dr. Lynn Brody, a physician herself can testify, they have a second consequence — anxiety. She got an MRI because of a family history of breast cancer and it showed a suspicious area.

“It was surprisingly nerve-wracking. Particularly since I work here and I am on the other side of either doing the biopsies or some sort of care-giving role.”

So who should be getting the sonograms or MRIs in addition to mammograms?

Dershaw says, “In the patient who has a personal history of breast cancer, who’s gene positive for breast cancer or has other factors that make the likelihood of her developing breast cancer extremely high, then looking at her breasts with an additional technique may be appropriate.”

For most women the mammogram, with all its limits, remains the foundation of breast cancer detection. With increasing use of digitized mammogram images, researchers are testing computerized reading devices — but for now the best hope is they will be a back up — not substitute for the radiologists’ trained eye.