Breast cancer screening guidelines spark a racial divide

In 2015, Philadelphia boasted one of the highest breast cancer screening rates in Pennsylvania. It ranked third among the 10 largest U.S. cities with 82% of women age 50 to 74 having received a mammogram in the previous two years, according to the city's community health assessment.

While good news for the city, the incidence and outcomes data generated by the screening campaign painted a harrowing picture for at least one subpopulation: Women from west Philadelphia had the highest breast cancer mortality rate in the city and surrounding suburban areas, despite lower rates of the disease.

Main Line Health's Lankenau Medical Center, which serves the community where more than 70% of the population is black and the average annual income is less than $30,000, decided to tackle what it saw as one of the root causes of the disparity. It moved to step up its already extensive mammography outreach campaign to include women under age 50.

And that made the program unique. Federal guidelines have recommended against routine screening for women under that age since 2009.

The rejection of federal guidelines in west Philadelphia is a response to a long-standing conundrum in cancer care: Race and ethnicity are closely correlated with survival rates, especially with breast cancer. Though black women are less likely to contract the disease, those who develop breast tumors are 42% more likely to die than their white counterparts.

Researchers have not come up with conclusive reasons for this disparate outcome. Yet many public health and civil-rights advocates point to one possible cause: the evidence that young black women are more likely to contract the disease than their white counterparts. Not only are black women under age 40 more likely to develop breast cancer than women from other racial groups, those under 35 have more than twice the breast cancer incidence rate compared with white women the same age, according to a 2009 National Institutes of Health-funded study published in the journal Seminars in Oncology.

And that has put a target on the latest recommendations from the U.S. Preventive Services Task Force, or USPSTF, whose guidelines for tests such as mammograms determine whether plans sold on the Affordable Care Act exchanges must offer the services free of charge.

“This is a civil-rights issue,” said James Rawlings, a clinical instructor of epidemiology at Yale and health chair of the Connecticut state branch of the NAACP.

Black women should be explicitly deemed “high risk, so that they immediately qualify for screening and mammography at younger ages and don't run into problems with insurers,” he said. The NAACP's national board plans to review the issue during its convention in July.

The USPSTF guideline writers did not find sufficient data to conclude that earlier screenings would reduce delays in treatment or the mortality disparities found in black women. “We just don't have enough information, one way or another, to tell us that,” said Dr. Kirsten Bibbins-Domingo, chair of the USPSTF and a professor of medicine and epidemiology at the University of California at San Francisco.

These subpopulations have been “worryingly understudied,” she said. The task force is required to follow the existing evidence.

About 12% of U.S. women develop breast cancer. Each year, more than 40,000 women die from the disease. The overall death rate has dropped 36% since 1989, which specialists attribute to an increase in mammography screening over the past three decades. The American Cancer Society estimates that such screenings reduce the risk of death from breast cancer by 20%.

Historically, black women have had much lower incidence of developing breast cancer than white women. In 2000, there were nearly 122 cases for every 100,000 black women compared with nearly 140 cases per 100,000 white women, according to the Centers for Disease Control and Prevention.

But that gap is narrowing because all of the incidence reduction has been concentrated among white women. The incidence rate among black women by 2012 had increased to 124 cases per 100,000 women while the rate for white women had stabilized at 128 per 100,000 women.

Yet the guidelines are based mostly on data generated from the group where incidence is declining. “A lot of the data that all these new guidelines are really based on is largely data from Canada, Scandinavia and places in the world where African-American women and even Latino women are underrepresented,” said Dr. Marisa Weiss, director of Lankenau's Breast Health Outreach program and president and founder of Breastcancer.org. “They really do not accurately reflect and don't apply to women who are at higher risk for getting breast cancer at an early age.”

When it comes to the over-50 population, white women are still more likely than black women to develop breast cancer. That's the age that USPSTF guidelines recommend women begin screening.

And there's evidence to suggest that screening isn't the determining factor for the poorer survival rates among black women in this older group. Those over 45 had the highest prevalence for undergoing mammography compared with other racial groups, according to a 2012 study.

There are numerous possible explanations for the disparity in outcomes. Some say it reflects gaps in access to care. Higher poverty and unemployment rates among minorities mean women are less likely to be able to afford treatment. Financial issues can lead women to ignore symptoms until the cancer has progressed.

But it's also true that breast tumors found in black women under age 45 are more likely to be more aggressive and therefore more difficult to treat. Advocates say this justifies expanding the screening guidelines to specifically target this group.

It's known that certain populations have higher risk, said Chinwe Onyekere, associate administrator at Lankenau. But those very women may miss the opportunity for early detection because the ages recommended for all women to start checking for the disease are too high, Weiss added.

When the task force in 2009 recommended increasing the age for routine breast cancer screening for women at average risk it was immediately controversial. Guidelines are set based on the average prevalence among all groups. That increases the likelihood that subpopulations affected the most by the disease will continue to be overlooked.

“This type of disparity just has not been taken into account in the studies leading up to the guideline in the guideline process, and it's really unfortunate,” said Dr. Debra Monticciolo, vice chair for research at Baylor Scott & White's radiology department and chairwoman of the American College of Radiology's Breast Imaging Commission. “Women in the black population and the Hispanic population are really being left behind.”

The American College of Radiology is only one of several organizations whose guidelines recommend beginning routine screening at ages earlier than 50. Others include the American Cancer Society and the American Congress of Obstetricians and Gynecologists.

Proponents of raising the recommended age note the lack of evidence to support the notion that screening at age 40 or earlier provides enough clinical benefit to warrant its use for women not at an elevated risk for breast cancer.

Such debate was the focus of controversy in 2009 when the USPSTF first upped the recommended age to begin routine breast cancer screening. It has moved from once a year at age 40 to once every other year, starting at age 50. That recommendation remained the same in its January update to the guidance.

Supporters of moving the age of initial screening reject the idea that it constitutes rationing. “Rationing means not getting care that you need,” said Dr. Rita Redberg, editor-in-chief of the medical journal JAMA Internal Medicine. “But the USPSTF and others are saying, 'You don't actually need this care.' And that is hard for people to hear.”

Increasing the number of mammograms in a population inevitably increases the number of false-positive results, which in turn leads to follow-up testing and unnecessary procedures such as a biopsies on people who do not have cancer. Mammography also leads to overdiagnosis since cancers are found that would not otherwise be a concern because they never progress.

The American Cancer Society estimates the rate of overdiagnosis because of mammography ranges from less than 5% to as much as 30%. “We need to deal with the fact that we don't have data to show that screening saves lives for women under the age of 50,” said Dr. Otis Brawley, chief medical officer for the American Cancer Society.

Last October, the ACS updated its screening guidelines for the first time in more than a decade. It changed the recommended age for women at average risk for breast cancer to begin routine mammography from 40 to 45.

Brawley opposes setting a younger age for black women to begin routine mammography. There is not enough evidence to support the notion that screening black women at a younger age would offer a benefit in terms of earlier diagnosis or improved health outcomes, he said.

But many on the front lines of cancer care reject that argument. “It's dangerous,” said Weiss of Lankenau Health. “The very group of women who are more likely to get breast cancer early are going to miss their opportunity for early detection.” Weiss said all women should begin routine annual screening at age 40, which she argued would particularly benefit black women.

Brawley said too much attention has been given to screening guidelines and not enough to addressing the disparities between black and white women when it comes to the quality and availability of follow-up care after a breast cancer diagnosis. “The missed opportunity is the opportunity to fix the quality of care that women receive,” he said.

That concern was raised in a 2012 study on disparities in breast cancer deaths in Chicago. The study suggested that where a mammogram is performed may result in a different outcomes.

Black and Hispanic women and those without private insurance were less likely to get a mammogram at academic medical centers. Those facilities tend to use breast imaging specialists and digital mammography, which are better at detecting early stage cancers as well as cancerous lumps in younger women and women with dense breasts, according to the study.

“A disparity in use of high-quality mammography may be contributing to disparities in breast cancer mortality,” the authors wrote.

But even getting the test in the first place can pose a financial challenge to patients if it is not recommended in screening guidelines. “If you don't qualify for screening, there's no reimbursement. No coverage,” Rawlings said. “Then you have a whole cohort that's not screened effectively. We're putting tens of thousands of minority women in harm's way.”

Others—such as Dr. Edith Mitchell, an oncologist and director of the center to eliminate cancer disparities at Jefferson University in Philadelphia—are concerned that doctors might be missing symptoms because they are too focused on what the guidelines recommend. Women who had breast discharge, swelling and other unusual symptoms have been told they were too young to have breast cancer. “I've seen this happen in people of different races,” Mitchell said. “Clinicians have to interpret the guidelines correctly and apply them appropriately to patients.”

A common theme stressed in all of the major breast screening guidelines has been for providers to talk with patients about mammography. The decision when to begin screening should be based on those discussions and the patient's preferences.

But Weiss argued that efforts to have those conversations can be hindered by recommendations that suggest younger women may have several more years before they need to begin thinking about getting checked.

Black women are also at higher risk of carrying genetic risk factors for developing breast cancer, which account for only 10% of cases in all women. A study last August in the journal Cancer found black women under age 50 have a higher prevalence of BRCA1 and BRCA2 gene mutations than rates known to occur in white women. Such mutations have been associated with an increased risk of breast and ovarian cancers.

Studies have found BRCA1/2 mutation carriers are at higher risk of developing triple-negative breast cancers, which occur in black women at a higher rate compared with white women. Triple-negative breast cancer can be difficult to treat because common treatments are usually ineffective.

But women without genetic mutations can greatly lower their risk by limiting alcohol consumption, not smoking and controlling diet and weight. Weiss worried that delaying the time women get routine screenings might also shorten the amount of time they have to lower their risk.

“If we were to promote this idea to start mammograms at 50, we're going to lose the opportunity to not just screen for early detection, but to have women take everyday steps that they can do to lower their risk for ever getting breast cancer in the first place,” Weiss said.