Women’s Imaging: New Age Talk
By Beth W. Orenstein
Vol. 22 No. 4 P. 6
Study: Breast cancer deaths in women under 40 stop declining.
The number of women in the United States younger than 40 who are dying from breast cancer is on the rise. Yes, rise—albeit very slightly. The slight rise in death rates among younger women ends a trend in the opposite direction that existed from 1987 to 2010, according to a study recently published in the journal Radiology.
The National Center for Health Statistics (NCHS) made mortality rates available starting in 1969. For the next 10 years, the NCHS says, the female breast cancer mortality rate for all US women remained unchanged. The next decade, from 1979 through 1989, the mortality rate increased 0.5% per year. However, by 1989, the age-adjusted female breast cancer mortality rate began to decline.
From 1989 to 2017, breast cancer mortality rates for all women in the United States decreased by 40%. The decrease was largely attributed to improved treatment and increased rates of screening mammography—modern mammography methods developed in the 1960s were first officially recommended by the American Cancer Society in 1976.
Led by R. Edward Hendrick, PhD, a clinical professor in the department of radiology at the University of Colorado School of Medicine in Aurora, the researchers questioned whether the decrease in breast cancer mortality rates from 1989 to 2017 occurred across all age subgroups. “So, we examined US female breast cancer mortality rates by age subgroups over time,” Hendrick says. The researchers looked at the NCHS long-term mortality data by age decade for all women aged 20 to 79 and at two broader age subgroups: women aged 20 to 39 and those aged 40 to 69.
They found that between 1989 and 2010, breast cancer mortality rates decreased significantly, by 1.45% to 3.45% per year for each age decade from 20 to 79 years. From 2010 to 2017, mortality rates decreased between 1.2% and 2.2% per year for each age decade from 40 to 79 years, but increased by a nonsignificant 0.5% per year in women aged 20 to 39 years. The researchers also found that, since the year 2000, the incidence of distant-stage breast cancer has increased by more than 4% per year in women aged 20 to 39 years.
Most invasive breast cancers occur in women who are at least 40 years old. However, 4% to 5% of cases occur in women younger than 40. Hendrick says the analysis makes it clear that “mortality rates in women under 40 are no longer decreasing.” He also believes that “in two to three years, the mortality rate will be increasing significantly in these women.”
Late-Stage Cancers on the Rise
Why has the decline in mortality rates in younger women stopped? Clearly, one reason is the rapid increase in distant-stage (metastatic) breast cancers in women aged 20 to 39, Hendrick says. “Our analysis went on to show that metastatic breast cancers in younger women have risen by more than 4% a year since the year 2000,” he says. However, he could not say why there has been such a rapid rise in late-stage cancers in these younger women. “That’s an area that needs more research,” he says.
Stamatia Destounis, MD, FACR, FSBI, FAIUM, a radiologist at Elizabeth Wende Breast Care in Rochester, New York, agrees with the authors that part of the answer is the higher rates of metastatic disease in women in the younger age group. “In fact, for women 20 to 39, the incidence rate of late-stage disease has increased by 4% a year since 2000, while in women 40 to 69, only 1.2%,” Destounis says. She also attributes the higher rate of metastatic disease in women younger than 40 to their not having the same opportunity for screening, “or call to screening, as women ages 40 and over do.”
The study should be a wake-up call to women under 40 and their referring physicians, Hendrick says. “Women under 40 years of age and their referring physicians should be aware that breast cancer is a possibility and that, when breast cancers occur in this age group, they tend to be fast-growing,” he says. “Women who feel a new breast lump, have bloody nipple discharge, or nipple inversion should be proactive in seeking medical care.”
Despite the findings, Hendrick says, the researchers do not recommend screening mammography for women under 40 years of age unless a woman is at high risk for breast cancer. Rather, he says, every woman should be encouraged to get a risk assessment for breast cancer by age 30. Such risk assessments would help identify those who might be at high risk for breast cancer and might benefit from early screening.
Destounis, who is a member of Radiology Today’s Editorial Advisory Board, agrees: Screening mammography affords women 40 and older the opportunity for radiologists to find small, very treatable cancers, but there are no screening guidelines for women younger than 40. Younger women tend to have more aggressive tumors and are more likely to have triple-negative cancers and human epidermal growth factor receptor 2–positive cancers, both of which are more aggressive subtypes, Destounis says. “Since there are no screening recommendations for women younger than 40, most of these young patients present after palpating their tumors,” she notes. “So, these cancers are larger and more advanced than screening-identified cancers that usually are not palpable.”
Lower Rates of Breast Self-Exams
Educating women early on regarding breast changes and breast self-exam has fallen out of favor by many organizations, Destounis says. It’s unfortunate, she adds, because “I would promote breast examination yearly by their health care providers for women starting in their 20s.”
The other side of this, according to the Hendrick paper, is that mortality rates in women aged 70 to 79 are decreasing, but at a slower rate than in women 40 to 69, Destounis says. According to the paper, since 2009, mortality rates in women aged 70 to 79 have decreased by 1.2% per year, while they have been decreasing by more than 2% per year for women aged 40 to 69.
Destounis believes the slower decrease in deaths among older women is most likely because many older women have stopped getting their yearly screening mammograms since 2009. That’s when the US Preventive Services Task Force changed its guidelines; it no longer endorsed screening for women over 74 and did not recommend breast self-examination.
In 2018, the ACR released a powerful manuscript by Debra L. Monticciolo, MD, vice chair of the department of radiology and section chief of breast imaging at Baylor Scott & White Medical Center in Temple, Texas, and the screening leadership group, Destounis says. The paper recommended all women, especially African American women and those of Ashkenazi Jewish descent, be evaluated for breast cancer risk no later than age 30. Destounis believes this is a highly important takeaway from the ACR manuscript, as it encourages women at higher risk to be identified sooner so they can benefit from supplemental screening. The American Cancer Society and others recommend that women who are at high risk for breast cancer based on certain factors should get a breast MRI and a mammogram every year, typically starting at age 30.
Monticciolo is also an author of the trends in breast cancer mortality Radiology study, as is Mark Helvie, MD, FACR, of the department of radiology and Comprehensive Cancer Care at the University of Michigan in Ann Arbor.
— Beth W. Orenstein of Northampton, Pennsylvania, is a regular contributor to Radiology Today.