Spotting What Mammograms Miss


BACKGROUND:  About one in every eight women in the United States will experience breast cancer in their lifetime.  Each year approximately 200,000 women will be diagnosed with breast cancer and around 40,000 women will die from it.  (Source: National Breast Cancer Association)
SELF-EXAMINATION:  Nearly 70% of all breast cancers are found through self-exams, and with early detection the five-year survival rate is 98%.  Researchers believe that taking a few minutes every month to perform a self-examination can make a lifetime of difference.  Breast self-exams can be performed lying down, in the mirror, or in the shower, to make sure you are doing it correctly.  Women should start performing self-exams as early as the age 20.  If a lump is found, then you should call the doctor for an appointment, eight out of 10 lumps are not cancerous.
THE NEXT STEP:  Starting at the ages between 20 and 39, women are strongly suggested to get clinical breast exams every three years.  By the age of 40 they should be getting baseline mammograms annually, especially if breast cancer runs in their family. 

  • Mammograms:  A mammogram is an x-ray picture of the breast.  They can be used to check for breast cancer in women who have no signs or symptoms, usually referred to as screening mammograms.  The machine can detect tumors that cannot be felt during a self-exam and deposits of calcium that shows the presence of breast cancer.  The machine can also be used to look more closely at an already detected lump, called diagnostic mammogram.  Signs of cancer include pain, skin thickening, nipple discharge, or a change in breast size or shape. Mammograms are also associated with potential harms, including false-negative results, false-positive results, the diagnosis and treatment of cancers and ductal carcinoma in situ lesions that would not have caused symptoms or threatened a woman's life (over diagnosis and overtreatment), and radiation exposure  Also, sometimes it is difficult to get a clear x-ray because of special circumstances like breast implants or women with dense breast tissue.  Often it cannot tell the difference between a tumor and dense breast tissue because they both appear white. (Source: www.NationalCancerInstitution.org).
  • Molecular Breast Imaging:  Molecular Breast Imaging is a new technique used to detect cancerous tumors that are not always visible in a mammogram.  A woman is injected with a radioactive isotope.  It accumulates in tumor cells more than it does in normal cells and the tumor then appears dark in a radiation detecting camera and is easy to see.  The procedure takes about 45 minutes for both breasts and does expose the patient to more radiation than mammography does.  However, a Mayo Clinic study found that MBI detected three times as many cancers in women with dense breast tissue and an increased risk of breast cancer than a mammogram did.  It also demonstrated fewer false positives, meaning the results appear abnormal but are noncancerous. 

WARNING:  Only a few centers in the U.S. are using the MBI approach because it is limited to research. Researchers are working towards reducing the amount of radiation the patient is exposed too. Only one MBI does not put off much, but if it is going to be used annually, then radiation needs to be reduced. (Source: www.mayoclinic.org).

Dr. Jamie Surratt, Radiologist, Baptist Medical Center with Mori, Bean and Brooks talks about molecular breast imaging.

What is MBI?

Dr. Surratt: MBI is molecular breast imaging and that refers to a technique where a radio pharmaceutical is injected and it seeks an area within tissue that has higher mitochondrial activity. And so specifically for breast it looks for tumor activity which is going to have more mitochondria or active mitochondria than normal breast tissue. And so the radio pharmaceutical is going to be concentrated in that area, it appears on the images as a dark spot.

We have other imaging what do you see that this does that the other ones don't?

Dr. Surratt: I think this is a really beneficial adjunct to mammograms and our other tests because it's a functional look at breast tissue rather than an anatomic. Mammograms are very good in detecting small cancers and breast tissue that's predominately fat density. It's easier to see through. And patients that have dense breast tissue that means there's more glandular tissue and fat, it's really hard to look for a small tumor that's also going to be white which is what dense breast tissue appears. So both appear white and it's hard to resolve something that's very small when it's in a background that's similar to its own appearance. So MBI is very helpful because it doesn't depend on the density breast tissue it's a separate way to image. I think the advantage over MRI is that it's sensitive like MRI but it's more specific. Sometimes MRI for us has created more questions than its solved but I think that each tool needs to be used in the context of what's going on with a specific patient and I do believe that we have to start with mammograms.

When do you use the MBI, when is a good time to use the MBI?

Dr. Surratt: In diagnostic imaging we use it for indications of a woman with very dense breast tissue; someone who has a family history of breast cancer but may not met the criteria set by the American Cancer Society of twenty percent or more lifetime risk. Insurance companies typically don't pay for adjunctive imaging with MRI unless you have greater than twenty percent lifetime risk. It can be useful in assessing recurrence versus scar tissue in a lumpectomy patient, response to therapy after preoperative or postoperative chemotherapy. It's a good problem solving tool when we've exhausted the usual mammogram, ultrasound, possibly MR. It's also advantageous in people that need to have an MRI but because of claustrophobia or a metallic implant aren't a candidate for MRI.

Have you seen this change the way that you manage cases?

Dr. Surratt: Yes. I can think of approximately eight patients out of the twenty two that we've already imaged that it's changed their management. And specifically the change has been patients didn't get an additional biopsy for an area that didn't have abnormal activity. And one case in particular a patient did go to surgery because the findings on MBI. She had been in a serial six month follow up for an asymmetry that was only seen in one view on the mammogram, had no palpable and no ultra sound correlate and she wasn't a candidate for an MRI. So MBI really helped this particular patient. She did go to surgery and lobular neoplasia was identified in the area. And that's a risk marker so that was resected.

Why is this such a great tool for women?

Dr. Surratt: I think the breakthrough in this is that it's so different than all of our other tools. So for the patient population with dense breast tissue where mammograms just don't answer the question this is a different way to image breast tissue. And so it really is a breakthrough because it doesn't depend on beast density. It's a functional test.

Why is this such a big deal now?

Dr. Surratt: I think it's such a breakthrough because it looks at breast tissue differently than any of our other modalities. It's a functional test. All of our other examinations are more of an anatomical type of testing. This is such a good adjunct to a difficult mammogram because it's going to look at activity on a cellular level whereas mammograms can only look at it at an anatomical level.

The only things that are going to turn black are only going to be cancer?

Dr. Surratt: There is a small group of lesions that are false positives just like with all of our other examinations. Again it would be related to entities where there would be more mitochondrial activity. So there's a rare entity called pseudoangioma and its hyperplasia or PASH, sometimes inflammation. A recent biopsy can sometimes show some increased activity, it's usually not intense but its increased background. It's been reported that there's been some uptake in fibroadenoma and papilloma. We do have one patient who had both a known breast cancer and a proven fibroadenoma in the same breast and there was a differential in the uptake the tumor being much more intense. More dark on the screen and the fibroadenoma had a lower level activity.

But this radioactive material goes directly to where it sees those places?

Dr. Surratt: Where there's more mitochondria activity it's going to be concentrated.

Tell me about the patient, for her it's more of peace of mind.

Dr. Surratt: I think peace of mind for her. This particular patient palpitated a lump and she had presence of implants and extremely dense breast tissue. And so for a mammographer that's just a difficult situation. They had done coned down spot compression views and really nothing showed up as being different in the mammogram. And so they did an ultrasound this area was just vaguely different from the tissue around it and all of our imaging tools depend on the entity being evaluated being different than the tissue around it. So the area that she palpitated was biopsied using ultrasound guidance but it's a very subtle finding on ultrasound. That was an infiltrating ductal carcinoma she had a lumpectomy and radiation and now this summer at the time of her first post lumpectomy mammogram she felt a lump. This lump is upper outer and again we don't see anything on the mammogram or ultrasound obviously she doesn't have confidence in mammogram and ultrasound at this point. And so she had an MBI and we're very happy to say that there was no abnormal uptake either breast on her MBI. So she's going to have an area that she palpitates as being different followed by her surgeon.

So in this case it's not a detection of something?

Dr. Surratt: Correct, I think it just gives her peace of mind that we've used all the tools that we have available. There's no abnormal activity in the area where she palpitates. And it's not uncommon for women to feel lumps and bumps in their breast but when you've had a history of breast cancer it just raises the anxiety level extremely.
Linda Allen
(904) 202-1891