Find out why a mammogram might not be enough.
Every year in the United States, about 264,000 cases of breast cancer are diagnosed in women and about 2,400 are found in men, according to the CDC. This year, Katie was one of them. On average, a woman has a roughly one in eight chance of developing breast cancer in her lifetime. In stark black and white, these sound like pretty alarming statistics — but the numbers don’t tell the whole story.
As is the case with all cancers, there’s a much higher chance of treating breast cancer successfully if it’s spotted early. A report released last month by the American Association for Cancer Research shared the encouraging news that survival rates for all cancers in the U.S. are on the rise. This is largely due to much-improved treatment methods, but also partly thanks to early detection. This is why screening for the disease, even if you don’t have any symptoms, plays such a vital role in managing it.
Breast cancer screening means checking breasts for cancer before any symptoms or signs begin to show. In a recent live event supported by Hologic, Katie spoke to Lisa Newman, MD, and Susan Harvey, MD, about when women should begin screening. Dr. Newman recommended discussing your breast health with your doctor as early as possible: “Women should start the conversation about their own breast health with their primary care providers as early as their 20s. Consider your family history, learn how to evaluate your own breasts, and be aware of the dangerous signs of breast cancer. Pay attention to things like a new lump in the breast, a lump in the underarm, bloody nipple discharge, or changes in the skin appearance of the breast.”
Once you have all the available information, you and your healthcare provider can then make an informed decision about what’s best to do next. As with any issue related to our health, the process of getting checked out can be daunting, but understanding what’s actually going on while your breasts are being examined is an empowering first step.
We’re breaking down the main methods used by doctors to look for breast cancer — and sharing some expert insight into what makes them so effective.
What are the main methods of breast screening?
The most common forms of breast screening are mammography, breast ultrasound, and MRI screening. Each has different benefits and drawbacks, but typically, breast screening begins with mammograms.
“Mammography is the gold standard screening exam for breast cancer,” explains Kiran Sheikh, MD, program director of diagnostic radiology at the nonprofit Yale New Haven Health System. “It’s a non-invasive and effective exam that allows early detection of cancer.”
A mammogram is an X-ray image of the breast used to spot early signs of cancer. One after the other, each breast is placed between two plastic plates, which flatten it and hold it still while the image is being taken. Images are taken from above and below the breast, and also from each side. Harmless fatty tissue shows up as dark on mammograms, whereas masses show up as white. Masses can indicate a number of things, including cysts and non-cancerous tumors — but they can also be a sign of cancer.
According to Dr. Sheikh, The Society of Breast Imaging and Academy College of Radiology recommends that women with an average lifetime risk for breast cancer start getting mammograms once they turn 40 years old. When speaking to Katie, Dr. Harvey and Dr. Newman agreed that average-risk women should initiate screening at age 40 and continue every year thereafter.
The ACOG and the American College of Radiology both recommend that all women be evaluated for their breast cancer risk by age 30. There’s no one size fits all, and for some people, it’s sensible to carry out additional checks where possible.
When do you get a screening breast ultrasound — and how does it work?
“Screening breast ultrasound is recommended in women with dense breast tissue, to be performed in addition to mammography,” explains Dr. Sheikh. “It can also be performed in high-risk women who can’t undergo breast MRI.”
“If mammogram films look white or have large areas of white, then the tissue is called ‘dense,’” says Lyris Schonholz, MD, diagnostic radiologist at Schonholz & Drossman LLP. “You must then ask for a screening breast ultrasound to be performed.”
Both dense breast tissue and masses show up as white on mammograms, and white-on-white is harder to see, Dr. Schonholz explains. On a breast ultrasound, dense breast tissue is white and masses show up as dark, making them easier to spot. Dr. Harvey agrees that breast ultrasound can be enormously helpful when trying to detect cancer: “Breast screening ultrasound…allows for a different way of looking at the breast tissue and can almost double the cancer detection that mammography and 3D mammography bring.”
“If a person with dense breasts has a mammogram and is told that the mammogram is normal, they often believe that they have been told that their breast is normal,” says Dr. Schonholz. “That’s not the full story. To actually know that the dense breast tissue is normal, the person would have needed a screening breast ultrasound.”
A screening breast ultrasound is necessary to make sure that cancer isn’t hidden within the dense breast tissue on the mammogram.
“I sometimes use this analogy,” says Dr. Schonholz. “Imagine a radioactive snowball has been thrown on a field of snow, and you have a few minutes to find it. You would say, ‘why did you make something so important to find also out of snow? Why didn’t you make it out of something easier to see?’ On screening breast ultrasound, what we are looking for would be like a lump of coal in this analogy.”
Dr. Schonholz stresses that a mammogram should always be performed before screening breast ultrasound to determine the type of breast tissue that is present, and indicate whether a screening breast ultrasound is needed.
“Mammograms must always be done because they see microcalcifications, which are different from masses,” she adds. “Microcalcifications look like specks of salt, and these are sometimes cancerous. Microcalcifications can’t be seen using breast ultrasound.”
Who’s considered to be at a “high” risk of breast cancer?
Women who have a more than 20 percent lifetime risk of breast cancer are considered “high risk.” For this group, additional screenings are recommended. “Breast MRI is recommended in high-risk women, to be performed in addition to mammography,” explains Dr. Sheikh. “High-risk women include those with BRCA1 or BRCA2 gene mutation; a history of chest radiation between the ages of 10 and 30; a strong family history such as premenopausal breast cancer in a first-degree relative; or women with genetic disorders such as Li-Fraumeni syndrome, Cowden syndrome, or Bannayan-Riley-Ruvalcaba syndrome.”
Dr. Sheikh recommends that high-risk women begin annual screening mammography and breast MRI by the age of 30. The earliest age that high-risk patients can start breast screening using MRI is 25 — if 25 is 10 years before the age of that person’s youngest affected relative, or eight years after chest radiation treatment.
How does a breast MRI work?
“A breast MRI is a diagnostic exam in which the patient lies face down with her breasts positioned within openings in the MRI table,” explains Dr. Sheikh. “Contrast is injected into a vein in the arm, and MRI images are obtained before and after the contrast is administered. The contrast helps detect small lesions that can be missed on mammography or ultrasound.”
Breast MRI is the most sensitive form of breast screening, and has the highest cancer detection rate of all the breast imaging exams, Dr. Sheikh says. This can make it difficult to distinguish between normal and abnormal findings and may potentially lead to unnecessary breast biopsies, which is one of the reasons it’s not used as standard. “Breast MRI doesn’t always detect stage 0 breast carcinoma, which may show up more discreetly as calcifications on mammography,” she adds.
Standard breast MRI is expensive, but abbreviated breast MRI — which acquires images more quickly — and contrast mammography have emerged as cost-effective imaging options for supplemental screening in average-risk women with dense breasts.
What’s the deal with 3D mammography?
Whereas 2D digital mammography typically only takes two images of each breast, 3D mammography, also known as digital breast tomosynthesis (DBT), takes multiple images of each breast at different angles. This allows the radiologist to evaluate the breast tissue by layers, explains Dr. Sheikh. DBT images offer a better view of abnormalities that might otherwise have been obscured by overlying tissue, meaning DBT has a higher cancer detection rate compared to 2D digital mammography. Dr. Harvey, agrees with this assessment, saying 2D mammograms allow doctors to look at a breast “from top to bottom” whereas the 3D method lets doctors see the breast in 1-millimeter slices. “This prevents overlap of breast tissue. It’s a more accurate interpretation.”
“According to the U.S. FDA Mammography Quality Standards Act and Program (MQSA) statistics as of the beginning of September, DBT currently accounts for 46 percent of the accredited mammography units in the United States,” says Dr. Sheikh. “Since its FDA approval in 2011, DBT units have been quickly rising in numbers, so it will likely become the more common modality for breast imaging in the next few years.”
Though the initial cost of a DBT examination is more expensive than that of 2D mammography, it’s potentially more cost-effective in the long run, since early detection lowers costs for the health system later down the line. Medicaid and Medicare now cover the 3D option, and if your current provider only works with the 2D method, you can ask your provider to recommend a facility that performs 3D mammograms.
What are the first steps that a woman should take to ensure she’s protecting herself as best she can?
“The goal of breast cancer screening is early detection of cancer before symptoms arise,” says Dr. Sheikh. “In addition to annual screening exams, women with intermediate or high lifetime risk must have an annual clinical breast exam performed by their health care provider.”
She adds, “In general, women should be familiar with their breasts and they should talk to their health care provider if they notice any change in their breasts, including focal pain, lump, erythema, skin thickening, skin retraction, nipple inversion, or nipple discharge that is spontaneous or bloody.”
