In 2000, 2 years after the death of her husband, Jay Monahan, from colon cancer, Katie Couric underwent a colonoscopy live on "The Today Show," leading to a 20% jump in national colonoscopy screening rates, something the University of Michigan dubbed the "Couric Effect."
Now, Couric is once again advocating for cancer screening.
On September 28, Couric wrote an , detailing her breast cancer diagnosis in June. During a routine doctor's visit, she was told she was due for a mammogram. Although she thought she had "just got one," her last mammogram was actually in December 2020. "Wait, what? How could that be? Had the pandemic given me a skewed sense of time? Had it messed with my memory?" she wrote. She made an appointment right away.
She had intended to film her mammogram to share on her website. If she had forgotten to make an appointment during the pandemic, surely others must have as well, and this could be a reminder for them, she said. While a technician filmed her, she underwent a 3D mammogram -- and because of her history of dense breasts -- a breast ultrasound.
Afterwards, her breast radiologist, Susan Drossman, MD, told her that there was something in her left breast that looked suspicious, recommending a needle biopsy to check it out.
The next day, Couric was diagnosed with stage IA HER2-negative breast cancer. She underwent a lumpectomy in July, followed by 15 rounds of radiation therapy. She will soon begin aromatase inhibitor therapy to lower her estrogen levels.
In a with Savannah Guthrie and Hoda Kotb, Couric explained her new mission to raise awareness of the need for breast cancer screening, noting that only 70% of eligible women receive screening (and this rate further decreased during the pandemic), and to educate women about dense breasts and how this condition may relate to breast cancer.
Couric said that 45-50% of women have dense breasts, which is diagnosed by mammogram. Having dense breasts makes detecting breast cancer more difficult. Supplemental screening with breast ultrasound is often recommended for these women. However, only 38 states have laws that require physicians to notify patients that they have dense breasts, and even in states that do, the notification doesn't necessarily clearly explain what to do with this information.
In addition, not all insurance plans cover breast ultrasound (only 14 states and Washington, D.C. require insurance companies to at least partially cover the test).
Couric is working with (D-Conn.) on legislation that would ensure that women and their healthcare providers have access to the information about breast density to make informed healthcare decisions. DeLauro will also introduce legislation this month that would require insurance companies to completely cover the costs for breast ultrasound for women with dense breasts.
Breast Cancer
Breast cancer is the most common noncutaneous cancer in women in the U.S., with an estimated 51,400 cases of ductal carcinoma in situ (DCIS) and 287,850 cases of invasive disease diagnosed in 2022, according to the . Although widespread adoption of breast cancer screening has increased the incidence of breast cancer, it also has changed the characteristics of the cancers detected, with increased numbers of lower-risk cancers, pre-malignant lesions, and DCIS.
Breast cancer is commonly treated by various combinations of surgery, radiation therapy, chemotherapy, and hormone therapy. According to the , selection of therapy may be influenced by the following clinical and pathological features:
- Menopausal status
- Stage of the disease
- Grade of the primary tumor
- Estrogen receptor (ER) and progesterone receptor (PR) status of the tumor
- HER2 overexpression and/or amplification
- Histologic type
The use of molecular profiling in breast cancer includes ER and PR status testing, HER2 status testing, and gene profile testing by microarray assay or RT-PCR (e.g., MammaPrint, Oncotype DX, Prosigna). On the basis of ER, PR, and HER2 results, breast cancer is classified as one of the following types:
- Hormone receptor positive
- HER2 positive
- Triple negative (ER, PR, and HER2 negative)
ER, PR, and HER2 status are important for determining prognosis and predicting response to endocrine and HER2-directed therapies.
Breast Density
Breasts contain glandular, connective, and fatty tissue. Breast density describes the relative amounts of these tissues. Dense breasts have relatively high amounts of glandular and fibrous connective tissue and relatively low amounts of fatty tissue.
Breast density is determined by mammography -- it is not something that can be determined by physical breast examination.
Breast density can be inherited, but other factors can influence it. Lower breast density is associated with increasing age, childbirth, and use of tamoxifen. Factors associated with higher breast density include use of postmenopausal hormone replacement therapy and low body mass index.
Breast density is categorized using a scale developed by the American College of Radiology called the Breast Imaging Reporting and Data System (), which helps radiologists interpret mammogram results. BI-RADS divides breast density into four categories:
- A: Almost entirely fatty breast tissue, found in about 10% of women
- B: Scattered areas of dense glandular tissue and fibrous connective tissue (scattered fibroglandular breast tissue) found in about 40% of women
- C: Heterogeneously dense breast tissue with many areas of glandular tissue and fibrous connective tissue, found in about 40% of women
- D: Extremely dense breast tissue, found in about 10% of women
Is There a Relationship Between Dense Breasts and Breast Cancer?
Yes -- in two ways. First, it is more difficult to detect breast cancer in dense breasts. Dense breast tissue and some abnormal breast changes, such as calcifications and tumors, appear as white areas in the mammogram. As a result, mammography is less sensitive in women with dense breasts. Women with dense breasts may be called back for follow-up tests more often than women with fatty breasts. Dense breasts can also put women at higher risk of interval breast cancer.
Secondly, multiple studies have shown that women with dense breasts have an increased risk of breast cancer. Women with extremely dense breasts have a four- to six-fold higher risk of breast cancer compared with those with fatty breasts. This is independent of the effect of breast density on mammogram interpretation.
Is supplemental testing warranted for women with dense breasts?
This is the big question, and unfortunately it hasn't been satisfactorily answered yet. The last recommendations from the U.S. Preventive Services Task Force in 2016 stated that "current evidence is insufficient to assess the balance of benefits and harms of adjunctive screening for breast cancer using breast ultrasonography, magnetic resonance imaging (MRI), digital breast tomosynthesis (DBT), or other methods in women identified to have dense breasts on an otherwise negative screening mammogram."
These recommendations are currently under review, and it is unclear when the updated recommendations will be released. Until then, women with dense breasts should have a discussion with their healthcare providers to tailor screening to each patient's breast density and overall lifetime risk of breast cancer.
A 2021 review outlined the benefits and limitations of the various available supplemental screening tests for women with dense breasts, including:
- DBT, which x-rays the breast in an arc for multiple-angle images that are reconstructed into a 3D image. This reduces overlap of images and increases the sensitivity of the mammogram. Many hospitals and larger centers use DBT as their standard screening mammogram; however, this technique is not available everywhere.
- Whole-breast ultrasonography has become a common supplemental screening method for many women with dense breasts. It is widely available, has no ionizing radiation, and can effectively differentiate between tissues of different densities (fluid vs soft tissue). It can also allow a physician to do a real-time biopsy of a suspicious lesion. However, it can lead to false-positive results.
- Breast MRI is the most sensitive test for detecting breast cancer. Like ultrasound, there is no ionizing radiation. It also reduces the risk of interval cancers. Compared with other modalities, it is more costly, requires a gadolinium contrast agent, and can't be used in patients with morbid obesity or those with severe claustrophobia.
Michele R. Berman, MD, is a pediatrician-turned-medical journalist. She trained at Johns Hopkins, Washington University in St. Louis, and St. Louis Children's Hospital. Her mission is both journalistic and educational: to report on common diseases affecting uncommon people and summarize the evidence-based medicine behind the headlines.