True Story Number 2

Carol is an executive of a major company. When she felt a lump in her left breast in August, Carol called her primary care physician who ordered a routine mammogram which was done in September. The mammogram showed a new small density in only one film of her left breast; and she was asked to return to the radiologist in October for more mammograms. The follow up mammograms were normal. Nothing was seen on the second set of mammograms.

However, because Carol had felt a lump, an ultrasound was done of this area and the ultrasound found a small, 8 mm mass (about 3/8 inch). At the end of October, a core biopsy was done by the radiologist; and the tissue from the core biopsy of her left breast contained breast cancer.

After two months of evaluation no one had examined Carol’s breasts. None of her physicians checked to see what could be felt in either breast.

Carol then went to see a breast surgeon who did a clinical breast examination (CBE) of both of her breasts. He saw the bruise in her left breast from the core biopsy; but he also noticed a small mass in her right breast – her opposite breast!

The surgeon then ordered a repeat mammogram to look again at the area he had felt during the CBE of Carol’s right breast. Again, the mammogram showed nothing. He then requested an ultrasound examination. The ultrasound showed a very small, 4mm mass in her right breast (less than 1/4 inch), which was what he had already felt by CBE.

Carol’s surgeon then did a simple fine needle aspiration biopsy (called an FNA or an FNAB). The FNA demonstrated that the mass in Carol’s right breast was also cancer.

Carol had cancer in both breasts. If she had relied on the mammogram, her doctors would have missed the cancer in her right breast; and the cancer in her right breast would not have been removed. She would have been treated for one cancer and the second cancer would have been left to grow.

In fact, if Carol had relied on her mammograms only, neither cancer would have been biopsied. Recall that Carol had a possible area seen on the first mammogram of her left breast; but her second mammogram, taken with special films that are supposed to show masses more clearly, actually did not show the cancer a second time. Carol’s left breast cancer was only found because Carol herself had found the mass. The radiologist did an ultrasound of the mass Carol had felt.

Carol’s right breast cancer was only found because her surgeon examined both of her breasts. He was not satisfied to stop just knowing she had one problem. He looked to be certain there was not a second problem.

Mammograms failed Carol; but clinical breast examination did what Carol’s mammogram was not able to do. It found her second cancer, after her own self-examination found her first breast cancer.

The reason that mammograms miss cancers is that the mammogram does not see a cancer like a light on a dark night. A mammogram sees breast cancer as a shadow. Some women, especially young women, have breasts that are so dense that the normal tissue makes a shadow. When the breast makes its own dense shadow, the shadow from the cancer cannot be seen.

To understand how this works, think about whether you can see the shadow of your hand on a sunny day – which you would expect to do – and then think about whether you would be unable to see the shadow of your hand on a day when clouds make a lot of shadows. If there is already a shadow you can’t see an added shadow. This is the same reason that a mammogram may not see the shadow from
a cancer in a dense breast.

The 15 percent of all breast cancers that are missed by mammograms effect more than 30,000 women every year in the United States alone. Diagnosis of their cancers is delayed unless they have a CBE along with their mammogram.