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The Latest in Mammogram Technology

09/26/2012 07:37 EDT | Updated 11/26/2012 05:12 EST
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If you Google the words, "mammograms suck" or "I hate mammograms," you'll find a long list of whining, griping, funny and sometimes poignant accounts of this nasty, yet necessary female procedure.

"Put your girls first!" "Don't procrastinate!" "The twins come first!" "Mammogram Schmammogram!"

On the day of my own yearly mammogram, a grumpy technician walks into the cold, dark room and begins, ever so nonchalantly, to wrestle one of my poor boobs into submission and I wince. Looking at me sternly, she says, "Mammograms are much easier for big-breasted women." Almost at a loss for words, I reply, "Well, that's certainly cold comfort, but thanks."

Clearly every woman experiences mammograms differently, but as you've no doubt gathered, I don't like them much at all.

It's uncomfortable, for starters. And, with an understandably indifferent technician readying my breast to be flattened into a pancake as she contorts my upper body in a less than gentle way to get "it" in the right position for the x-ray -- all the while terrified the machine won't stop and will blow my breast to smithereens -- I know it's not her fault but I feel a certain indignation rise up in me. And something else rises up in me, in the form of a query. You know the one, that age old question asked about all medical instruments used on the female body: "Who invented this device?"

Overreacting? Okay, maybe just a bit. Still, I can't help but wonder out loud, "How horrible must this test be for women who do have breast cancer?"

The still grouchy technicians replies, "We have different tests for them." This time I keep my cheeky reply to myself: "Guess some people aren't meant to work with boobs all day."

In spite of the wild indignation that having my breasts squished conjures up in me, I thank God for these technicians and radiologists because without them, we'd all be a lot worse off.

As I'm going through my yearly mammography experience, and the subsequent recall I get because the first series didn't take, (guess I shouldn't have been such a crank), I realize there's information overload out there about breast screening and who needs it and when.

For instance, a friend recently told me that she heard small-breasted women don't get breast cancer as often as big-breasted women do, so she's okay -- but this is false. Ministryhealth.org states, "Breast size has nothing to do with a woman's vulnerability to cancer or other breast disease."

Yet another misconception is that only women with an ancestral history of breast cancer are at risk. Breastcancer.org states: "About 85% of breast cancers occur in women who have no family history of breast cancer. These occur due to genetic mutations that happen as a result of the aging process, rather than inherited mutations."

Canadian bio-identical hormone pioneer and gynecologist Dr. Alvin Pettle says: "Women should closely watch for any changes of their breasts." Confirmed at Ministryhealth.org, "Changes to the outside of a breast may indicate a problem within it. Dimpling, puckering, flattening, indentations and other changes seen on the outside of the breast may indicate a problem within the breast."

Pettle says women should regularly monitor the shape of their breasts. He suggests standing in front of a mirror with your arms suspended at either side, and carefully look to make sure the roundness on the outside of the breasts remain the same. If there are changes, tell your doctor. Pettle also says women should limit the amount of alcohol and red meat they consume because it raises estrogen in the body. "It's a good idea to talk with a health care practitioner about finding the right supplements to support breast health -- there are lots of good supplements out there," adds Pettle.

Another friend told me she would never get a mammogram because she's afraid that there's too much radiation and so she only goes for breast examinations and ultrasounds.

But women who fear high dosages of radiation from mammography can take heart because many clinics in Canada are now doing digital mammography, which is a step up from analog.

Joanne Muldoon is a product sales specialist with U.S.-based Hologic Inc., she says, "The high radiation myth is based on older technology. Advanced mammo techniques, such as 2-D digital mammography, and now 3-D breast tomosynthesis, give a much lower dose of radiation." Muldoon stresses, "Having a mammogram far outweighs the risks and one of the benefits of having the test is early detection."

Tomosynthesis is an emerging technology to help improve specificity and sensitivity, compared to routine mammography. Muldoon says, "It's a 3-D image of the breast to see through superimposing features in the breast that could be missed on the 2-D currently used."

With all the information out there, I set out to get some answers from the Canadian Association of Radiologists. I was put in touch with Dr. Nancy Wadden who is MD chair of the Mammography Accreditation Program of the Canadian Association of Radiologist. She is also medical director of the Breast Screening Program for Newfoundland and Labrador, and associate professor in the Faculty of Medicine at Memorial University of Newfoundland.

Q: The new digital mammography machines, which are replacing the older analogue machines, are filmless, what makes them better for patients?

A: Analogue mammography machines use a film/screen combination to capture the image of the breast. The image of the breast is displayed on the film. This is a complex process and there are many steps that must be optimized to ensure the image is the best that it can be. Some of these include the performance of the mammography machine, the positioning of the breast, the technical factors used to produce the image, the quality of the film and the functioning of the processor for development of the film.

A lot of effort goes into ensuring that all of these parameters are optimized. The display of the image of the breast on the film is then read by the radiologist on a light box. CR (computed radiography) mammography uses the same mammography machine as film screen mammography. The image is captured with a digital receptor and this image is run through a digital reader.

The information is then sent to a computer monitor where the image can be manipulated for things such as contrast, brightness and magnification. FFDM or DR (full field digital mammography) uses a digital unit where the image is captured directly onto a detector. This image is sent to a viewer when the image can be optimized and manipulated.

The production of the image and efficiency of the capture of the image is improved with DR over CR. With DR, computer programs are applied to the image information to reconstruct the image to maximize the contrast and allow better visualization of any potential abnormality. The breast is a very low contrast structure that is inherently difficult to image.

With analogue units, the image information and the display of the image are linked and cannot be manipulated further to improve the display in the differences in subtle areas of contrast difference. The advantage of CR and DR over analogue units is that the image information and the display are separated and can therefore be manipulated to maximize the differences in contrast. The image can also be magnified and manipulated to improve brightness.

DR does this in a better way than CR and this is why facilities are converting from CR to DR, but DR is more expensive than CR. Facilities that had a good analogue unit were able to make the transition to CR and gain many of the advantages of digital mammography without the incurring the large cost of DR. Once these CR units need replacement, it is logical to consider DR."

Q: What steps does the radiologist go through while analyzing a mammography?

A: The mammogram can be performed for either screening (the woman has no symptoms), or for diagnosis (the woman has symptoms or a particular abnormality is being looked for). When a screening mammogram is performed, in the majority of cases, it is normal. In about 5 per cent to 10 per cent of the cases, a potential abnormality will be detected.

The woman will be recalled for more views (spot compression views or magnification views) and/or ultrasound of an area of the breast identified on the screening mammogram as potentially abnormal. Occasionally, an MRI will be required. In the majority of cases, the initial potential abnormality on the screening mammogram will be found to be normal with these extra tests. In a small number of cases, a biopsy will be required.

Even then, about half of the abnormalities biopsied will be shown not to be cancer. In the case of a diagnostic mammogram, both breasts as well as the area of concern are examined. Sometimes, depending on the findings on this diagnostic mammogram, an ultrasound will be required.

Q: Why does the breast have to be compressed so hard in order for radiologists to see tissue?

A: Compression is required for a number of reasons. First, there must be no movement of the breast when the image is being taken. Any motion on the image will obscure the structures. Motion on the image will require the image to be repeated. In addition, a cancer can be obscured by motion. Second, the tissue is better visualized when the breast is as thin as possible. Compression decreases the breast thickness, decreasing the overlap of tissues and the possible obscuration of a cancer. A thinner breast also absorbs less radiation, decreasing the radiation dose to the breast.

Q: Who should get a mammogram?

A: A screening mammogram is performed when the woman has no symptoms. Generally speaking, women aged 50 to 74 should have regular mammography. If there are no significant risk factors for breast cancer, the mammogram can be performed every two years. If there are significant risk factors, the mammogram should be performed every year. Those significant risk factors include:

• History of breast cancer is a first degree relative (mother, father, sister, brother, daughter or son)

• Four or more second degree relatives with breast or ovarian cancer (aunt, uncle, grandparent or half sibling).

• Personal history of ovarian cancer before the age of 50.

• Previous breast biopsy that showed atypia including lobular carcinoma insitu (LCIS), atypical ductal hyperplasia (ADH) or atypical lobular hyperplasia (ALH).

• Personal history of breast cancer. It is the CAR's position that there is evidence to suggest that women age 40 to 49 also benefit from screening mammography. Cancers in this age group are less common as increasing age is the most important risk factor.

• The evidence for screening is less compelling than in women aged 50 and over, so the woman should discuss the pros and cons of mammography with her family physician if she is unsure. If women in this age group (premenopausal) choose to be screened, mammography should be performed on an annual basis as there is evidence that in some cases if a cancer is present, it can grow faster than in postmenopausal women. For women with a first degree relative with breast cancer, screening should begin five to 10 years prior to the age at which the relative was diagnosed, but not before the age of 30. These women should have annual mammography.

Q: Is it important for women to consent to have a mammography done, and if so, why?

A: Informed consent is important as the benefits and harms of any test should be known prior to the test being performed. There is a very small dose of radiation that is received with each mammogram and although the risk of radiation induced cancer is extremely small and theoretical, the woman should be aware of this and how this balances the benefit of potential early detection of a cancer.

A potential abnormality may be detected on the mammogram that could lead to extra tests, such as spot compression views, magnification views, ultrasound, MRI or even biopsy. In the majority of cases, the final result will be negative and these tests could be considered "unnecessary." In addition, a small number of cancers will be detected that might not have ever become clinically evident (over-diagnosis). Thus the woman will be diagnosed and treated for a cancer that would never have shortened her life. It is impossible to determine which mammographic abnormality will be an "over-diagnosed" or non-aggressive cancer, and what will be a more aggressive cancer, which when treated, might extend the woman's life. Women should be aware of the harms as well as the benefits of screening.

Q: What does an ultrasound reveal?

A: Ultrasound measures the transmission of sound waves through tissue. It is an excellent modality for evaluating an abnormality that is clinically palpable, or for certain findings on the mammogram, but it does not reliably detect cancers that are asymptomatic. At this point in time, it is not a reliable screening tool. It does not reliably identify fine calcifications that can be an indicator of early breast cancer. Mammography is the only tool that has been proven to reliably detect breast cancer. However, mammography still can miss some cancers as it is not a perfect test.

Q: When is an MRI needed?

A: MRI has several indications and can be helpful for evaluating an abnormality seen on a mammogram or ultrasound. It is used for screening women that are at a very high risk of developing breast cancer, but it is used in conjunction with mammography. It may detect small cancers before they are seen on the mammogram. However, it does not detect all cancers and there are some cancers seen on mammography that are not detected with MRI. In addition, occasionally, the mammogram is required to properly interpret the MRI. There are also false positive results seen with MRI that could require biopsy. Research has shown that in women with a very high risk of developing breast cancer, it is worthwhile to perform MRI screening as the benefits often outweigh the harms of unnecessary biopsy.

Q: Are there other technologies available for breast imaging?

A: Tomosynthesis, PET scanning, and nuclear medicine imaging are other technologies currently available. These are ancillary tools and as yet not proven to be effective for screening. Automated whole breast ultrasound is still in research stages.

Q: What's primarily used in North America?

A: In North America and the rest of the modern world, mammography is the test of choice for population- based breast cancer screening. No other modality has been proven effective for screening. As mentioned, MRI is used in conjunction with mammography in women who have a very high risk of developing breast cancer. Ultrasound is used for screening in some situations, but it should not be used without mammography and cannot replace mammography.

Q: What is the gold standard in breast imaging?

Mammography is still the gold standard for screening and the first step in diagnosis. Full field digital mammography has been shown to detect more cancers than analogue mammography in premenopausal women and women with dense breasts.

So, while my breasts and millions of other women's breasts around the world are squished and squeezed and analyzed by mammography machines, I am grateful to be able to have the test at all.

Sitting in the waiting room with the other women there to have the tissues deep within their breasts examined, it's clear it can be an unnerving experience.

Still, we all give each other knowing glances, albeit with a slight feeling of anxiety because no matter how scary, we are grateful for the people working to make sure everything is all right in spite of the temporary discomfort of the machines.

And, of course, remembering that early detection is everything.

Here! Here! The twins come first.