A recent study has found that most deaths from breast cancer occur in younger women who do not receive regular mammograms.
The study was published online in “CANCER,” a peer-reviewed journal of the American Cancer Society.
Researchers from Harvard University followed invasive breast cancers diagnosed in certain Boston hospitals between 1990 and 1999 and followed those cases through 2007.
Among 609 confirmed breast cancer deaths, 71 percent were women who had not been screened for breast cancer, according to the study. The remaining 29 percent were among women who had received mammograms.
Of all the breast cancer deaths in the study, 50 percent occurred in women under age 50. Only 13 percent occurred in women aged 70 or older.
The study concluded that women should receive regular mammograms before age 50.
“The biological nature of breast cancer in young women is more aggressive, while breast cancer in older women tends to be more indolent. This suggests that less frequent screening in older women, but more frequent screening in younger women, may be more biologically based, practical, and cost effective,” study author Dr. Blake Cady, professor of surgery (emeritus) of Harvard Medical School in Boston, said in a press release.
Dr. Marzban Rad, the sub-chief for breast imaging for Kaiser Permanente in the Napa-Solano area, was not involved in the study but agrees with the findings. Rad said he recommends that most asymptomatic women should start screening mammography at age 40. This is the current recommendation of the American College of Radiology and the American Cancer Society, he said.
“Despite the advent of other technologies (ultrasound and breast MRI), screening mammography remains crucial in the early detection of breast cancer,” Rad said.
In recent years, the use of mammograms to prevent breast cancer has been somewhat controversial. In 2009, the United States Preventive Services Task Force proposed to limit screening to women ages 50 to 74. But the American Cancer Society has continued to recommend breast cancer screenings to begin at age 40 — and the data from the recent Harvard study supports that recommendation.
The Harvard study also showed changes in survival rates from breast cancer associated with the introduction of screening. In the 1960s, half of women diagnosed with breast cancer died from the disease. With early detection and mammography, survival rates have increased. Among the women included in the study (who were diagnosed between 1990 and 1999), only 9.3 percent had died from breast cancer.
Many physicians, including Dr. Rad, insist that early detection saves lives, and it may also prevent women from needing more invasive surgeries.
“By detecting breast cancers early when they are smaller, we can more often perform Breast Conserving Therapy (BCT), also known as lumpectomy,” Rad said. “We can resect these malignancies before they spread to lymph nodes in the under arm region (the axilla) and thus obviate the need for invasive axillary surgery.”
While mammograms can sometimes lead to “false positives” — meaning the screening detects something that turns out to be non-cancerous — there’s also a risk of “false negatives.”
Younger women (closer to age 40), often have denser breast tissue which may obscure small masses, Rad said. For better detection, digital mammography should be used, he said.
“We offer digital mammography at all our Kaiser facilities in Napa Solano,” Rad said. “Digital mammography has better tissue contrast and is more helpful in evaluating younger/denser breast tissue.”
There is also some debate as to when screening mammography should stop.
“Most physicians believe that if a patient is healthy and has at least 10 healthy years of life remaining, then screening mammography should continue,” he said.
The biggest risks for developing breast cancer is being a woman and getting older, Rad said. Risk increases the older a woman gets. Other important risk factors include having a first-degree relative with breast cancer (mother, daughter, sister), breast-feeding (breastfeeding is generally thought to reduce risk), weight (maintaining a healthy Body Mass Index), and decreasing alcohol consumption, Rad said.
Having an active lifestyle is also “very good and encouraged,” he said.
“Understanding one’s risk for developing breast cancer is very important,” Rad said. “It is important for women to understand that ‘risk’ is the chance that something will happen, and not that it definitely will happen.”