Breast cancer, a disease in which atypical cells grow out of control, mainly develops in the lobules or ducts of the breast. While breast cancer is rare in men, it’s the most common form of cancer among women.
No one knows exactly what causes breast cancer, but it affects one in eight women at some point in their lives. This means that about 230,000 women in the US are diagnosed each year, and about 40,000 women die annually from breast cancer.
Breast Cancer Risks
Studies show that some women are at a higher risk of breast cancer than others. Risks include age, genetic mutations, family history, early onset of menstrual periods and dense breast tissue. But you can’t go by risks alone as a predictor of the disease. According to the American Cancer Society (ACS), many women with known risk factors may never develop breast cancer, while some women with no risk factors may get the diagnosis.
Still, women could control some of the risks, including alcohol intake, weight, physical activity and cigarette smoking. “There's actually pretty good data that shows a link between smoking and increasing your breast cancer risk,” says Alene Wright, MD, a general surgeon with the Medical Center of Trinity, in Trinity, Florida. There's also reasonable data, according to Wright, that postmenopausal obesity – that is, a body mass index (BMI) above 25 after going through menopause – can increase breast cancer risk since estrogen levels in overweight or obese women are higher. “Fat cells increase estrogen in low levels even when your ovaries aren’t working any more,” says Dr. Wright. “Many breast cancers are stimulated by estrogen.”
Because of the wide variability in who does – and doesn’t – develop breast cancer, knowing the signs can help you to be more alert to any changes in your breast and share them with your doctor.
Breast Cancer Signs and Symptoms
“I think the most important thing for women to know is sometimes there are no signs of breast cancer, and they're picked up on actual routine screening mammography,” Wright says. Other women may experience a lump in her breast that lasts longer than one menstrual cycle, a change in color or thickness of the skin on the breast or pain in any area of the breast.
Other symptoms include:
Importance of Self-Exams
While yearly screenings are important, the disease doesn’t always take a full year to develop. This is where performing self-exams can play an important role in identifying changes. “Some institutions find no value in performing self-exams,” says Wright. “I disagree. I think that women should be self-aware and examine themselves once a month at the same time of the month,” says Wright. “If they feel that there's something new or different from their previous self-exam and it persists more than four weeks, they should have it checked. I have diagnosed many breast cancers because a woman has self-palpated her own breast lump, even if she had a normal mammogram within the year.”
When to Start Screenings
Different institutions also have varying recommendations on when to start getting mammograms. The ACS recommends that women with average risk get annual screenings starting at age 45 and switch to mammograms every two years at age 55. The ACS further recommends that women with certain higher risk factors, such as having a first-degree relative with a BRCA 1 or BRCA2 gene mutation, should have an MRI and mammogram performed annually starting at age 30. The U.S. Preventive Services Task Force (USPSTF) recommends that women who are at average risk get screened every two years from ages 50 to 74, leaving it to a woman’s discretion to start in her 40s. But the USPSTF also says that women at higher risk may benefit from starting screenings in their 40s.
While each woman must make a decision in consultation with her doctor, “I would recommend that a woman with average risk, meaning no strong family history, no prior history of breast concerns or breast biopsies, start at age forty and have a mammogram once a year,” Wright says. Given the various recommendations, why forty? “Age forty is usually a compromise into when women start approaching the age of menopause,” says Wright. “And we know that breast cancers tend to be more common in women who are menopausal.”