Some breast cancers are on the rise — while others will become less common. The reasons why are fascinating. (Photo: Getty Images)
Breast cancer is already the most common form of cancer. We’ll see 234,000 new cases of the disease diagnosed this year alone — but according to new data presented at the American Association for Cancer Research’s 2015 Annual Meeting, that number is only set to rise substantially in the years ahead.
According to the research, breast cancer rates will increase by 50 percent by the year 2030, compared to stats analyzed from the year 2011 — a risk that’s especially potent in women over 70. Around 40 million women in the U.S., born between 1946 and 1964, will experience high absolute risks for postmenopausal breast cancer — or two to four percent risk over a decade-long span. Another 56 million women in their 20s and 30s will see a substantial risk of premenopausal cancer, around 0.4 percent to 1.5 percent over a 10-year span.
On the current trajectory, the total number of breast cancer cases will jump from 283,000 in 2011 to 441,000 in 2030. Although the number of diagnoses among women 50 to 69 should see a drop, the proportion of women seeing a breast cancer diagnosed between ages 70 and 84 will rise from 24 percent to 35 percent. This is mostly due to a jump in ER-positive, in-situ cancers, generally found by mammography, from 19 percent to 29 percent.
These numbers seem staggering, but, when you look at the reasons why, they make more sense:
1. Baby boomers are aging: There will be more women at an age where they experience a higher risk for breast cancer.
2. People are living longer. As women age, they’re more likely to develop breast cancer.
3. Estrogen positive breast cancer is on the rise.
Researchers delved into national data on breast cancer rates using projects run by the Census Bureau: NCI Surveillance, Epidemiology, and End Results Program. Then they used mathematical models to help forecast incidence of the disease, gleaning insights into the eventual burden of these cases and how we should approach prevention.
According to Richard Bleicher, MD, associate professor of surgical oncology and breast surgeon at the Fox Chase Cancer Center, these statistics are a reminder that we can’t get lax about testing and symptom checks. “It emphasizes the fact that screening is important,” he tells Yahoo Health. “There’s been a lot of controversy lately about mammography, the reliability, effectiveness and false positives — but mammography is still our front lines in detecting cancer.”
Bleicher also insists that it’s important for every woman to know the symptoms of cancer — whether she has family history and other risk factors, or not. “We hear different numbers, like one in eight women, or one in 11 women will develop cancer,” he says. “But it’s difficult to provide an exact estimate of cancer risk in the absence of a genetic mutation, which we know can lead to a 40 to 80 percent lifetime risk of developing breast cancer.”
It’s important to be aware of changes in your body. In addition to a lump in the breast, which most women know about, he says other reasons to see a doc include bloody discharge from the nipple, a lump in the armpit or changes to the contour of the skin.
However, no woman is immune to breast cancer, and all should be watchful. “It’s more common to get breast cancer in the absence of risk factors,” Bleicher says. “This is called sporadic cancer. Sometimes it’s due to various types of tissues having a high rate of cell turnover, or a hormone change, but the point is, even though you may do everything right — eat right, exercise, stay at a healthy weight — you may still get it.” Which is why you should know the signs, get regular screenings, and take active steps to reduce your risk.
On a positive note from the study, the researchers involved in the current study believe we’ll see fewer tough-to-treat cancers, like HER2-positive and triple-negative subtypes of breast cancer, as well as fewer estrogen receptor (ER)-negative tumors.
Why the drop in certain types? No one’s sure, but researchers are delving into clues. As an example, the trend in delaying motherhood and choosing to breastfeed may have something to do with a the reduction in the rates of these cancers, as early age at first birth and lack of breast-feeding are both risk factors for ER-negative tumors.