Breast Cancer Archive

Before you get your next mammogram, learn the pros and cons of this controversial screening test.

Once a year, we subject our breasts to the ritual ordeal of poking, prodding, and viselike squeezing known as a mammogram. We willingly endure this process because we know—or at least hope—that if we do get breast cancer, a mammogram will pick it up early enough to treat it and save our life.

Breast cancer isn’t just a woman’s disease. Men can get it, too—about 1% of breast cancer is diagnosed in men. Since few men know that, they often fail to recognize its earliest signs and end up seeing a doctor later in the process than women do. The result: Men face treatment for larger and more advanced tumors, and their cancer is more likely to have spread to other parts of the body. The largest study to date on outcomes in men with breast cancer indicates that the five-year survival rate for women with breast cancer was 83%, compared to 74% for men. Even men diagnosed with early stage breast cancer still fared worse than women, although the gap closed for men and women diagnosed with later-stage disease. Since breast cancer in men isn’t often on doctors’ radar screens, men should be aware and check themselves.

Radiation to treat breast cancer increases the risk of developing narrowed coronary arteries in areas that receive the most radiation, according to a study. Because most of the heart is located in the left side of the chest, the greatest concern is for women who receive radiation to the left breast. Prior studies linked radiation for breast cancer to an increased risk of developing heart disease later.

Swedish researchers evaluated the angiograms of 123 Swedish women who underwent radiation therapy for breast cancer between 1970 and 2003. Those with left-sided breast cancer were about four times more likely than those with right-sided breast cancer to have moderately narrowed coronary arteries, and seven times more likely to have severe narrowing (Journal of Clinical Oncology, published online Dec. 27, 2011).

Women who undergo breast-conserving surgery (lumpectomy) for early-stage breast cancer usually receive radiation therapy as a part of their treatment. Radiation kills cancer cells left behind after surgery and helps prevent them from causing a recurrence or spreading to other tissues. For example, in a 2011 study in The Lancet involving more than 10,000 women treated with breast-conserving surgery, radiation cut the 10-year recurrence rate by one-third to one-half. Numerous studies have found that mastectomy (which removes the entire breast) is no more effective than lumpectomy plus radiation in improving survival rates. (Radiation may also be given after mastectomy, depending on the size of the cancer or extent of its spread.)

The main serious downside of radiation is potential damage to the heart. Several studies have found that women who receive radiation for breast cancer have an increased risk of heart disease and death from cardiac causes. It's a special concern for women with left-sided breast cancer, because the heart is mostly in the left chest. Since the early 1990s, technical advances have been introduced to lower the risk of exposing the heart to radiation. But it's unclear how much these newer techniques help — partly because heart disease usually develops more than 10 years after exposure, and follow-up studies have been too short. Also, it hasn't been clear exactly how radiation damages the heart.

The FDA today revoked its 2008 approval of the drug Avastin to treat breast cancer, concluding that the drug does little to help women with breast cancer while putting them at risk for potentially life-threatening side effects. Avastin will remain on the market (and so be potentially available to women with breast cancer) because it has also been approved to treat other types of cancer.

A 28-year study of 106,000 women found that moderate alcohol slightly increases a woman’s risk of developing breast cancer. Women who had the equivalent of three to six drinks a week had a modest increase in their risk of breast cancer (15%) compared to women who never drank alcohol. That would translate into an extra 3 cases of breast cancer per 1,000 women per year. The risks were the same for wine, beer, and spirits. Because moderate drinking appears to prevent some types of heart disease—which affects more women than breast cancer does—it’s important for women to think about alcohol in light of their own personal health situation.

Some lifesaving cancer therapies can harm the heart and arteries (Harvard Heart Letter, March 2010). Trastuzumab (Herceptin), a drug used to treat one type of breast cancer, has improved survival for women, but it can also weaken the left ventricle, the heart's main pumping chamber.

One study suggests that the problem may be more common than researchers had initially suspected, especially among older women. A team of researchers from Vall d'Hebron University Hospital in Barcelona, Spain, reviewed the medical records of 45 women ages 70 and older who were treated with trastuzumab. Four developed heart failure, and another eight had declines in a measure called left ventricular ejection fraction, indicating a problem in the left ventricle. Eleven of the women recovered after stopping trastuzumab, though recovery sometimes took as long as 21 weeks. In one woman, heart failure persisted (Annals of Oncology, published online Aug. 9, 2011).

Women whose breasts appear dense on mammograms have a higher risk for some aggressive breast cancers.

One of the strongest known risk factors for breast cancer is high breast density — that is, relatively little fat in the breast and more connective and glandular tissue, as seen on a mammogram. Now, a study has found that higher breast density in postmenopausal women increases the risk of specific types of breast cancer, including some that have a relatively poorer prognosis.

Not all women have the same risk for developing breast cancer over a lifetime. Certain factors increase a woman’s risk, and some have a bigger impact on risk than others. However, having several risk factors doesn’t mean you’ll inevitably develop breast cancer. Likewise, having few risk factors doesn’t mean that you’ll never develop it.

Many risk factors, such as age and gender, are not within our control. Others, especially those related to personal behaviors, can be modified.

A breast cancer drug raises hope for chemoprevention.

One major story that came out of the American Society of Clinical Oncology (ASCO) meeting in June 2011 focused on a study of a drug called exemestane (pronounced ex-ee-MESS-tane). Exemestane is in a class of drugs called aromatase inhibitors, which women take for several years after they've been treated for breast cancer to reduce the chances of getting breast cancer again. Aromatase is an enzyme that's crucial to the production of the hormone estrogen, which in many cases fuels the development and growth of breast cancer. So by inhibiting aromatase, exemestane lowers estrogen levels and therefore the risk of breast cancer recurrence.

The results reported at the ASCO meeting (and published simultaneously in The New England Journal of Medicine) were from a study testing whether exemestane might be able to prevent invasive breast cancer. The 4,560 postmenopausal women (average age, 62.5) who volunteered to be in the study had never had invasive breast cancer, although they did, for various reasons, including their age, have a higher-than-normal risk for getting it in the future. Half the women took exemestane daily; the other half, a placebo. After three years, 11 (0.5%) of the 2,285 women who took exemestane had developed invasive breast cancer, compared with 32 (1.4%) of the 2,275 women who took a placebo.