Myth Taking birth control pills can give you breast cancer.
Fact Most experts believe that taking birth control pills does not increase your risk of breast cancer, even if you have a relative who has had the disease and even if you take the pill for many years.
Breast cancer in this country has been on the rise since about 1940, growing about 4 percent yearly during the 1980s. The increase leveled off in the 1990s and the incidence currently stands at about 101 cases per 100,000 women. Much of the increase took place among older, postmenopausal women; women are living longer, and mortality from other diseases has gone down. In other words, women are living long enough to get breast cancer. Only about 5 percent of breast cancer occurs in women younger than 40, and only 25 percent in women younger than 50.
One statistic that gets a lot of attention is that the lifetime risk of getting breast cancer rose from 1 in 9 in the early 1980s to 1 in 8. The change comes about partly because in the early 1990s the National Cancer Institute changed its statistical pool, including cancers diagnosed in women over the age of 85, a group at relatively high risk, and extending the statistical lifetime to no years (an age most women will not attain). While the 1-in-8 figure is frightening, it does not mean that of any group of sixteen women sitting together in a room, two will get breast cancer. It does mean that each baby girl born in America has a 1-in-8 chance of getting breast cancer at some point in her lifetime if she lives to be no. Her chance increases significantly with age.
If you are between the ages of 20 and 24, the chance that you will get breast cancer during the next ten years is only 1 in 2,500; if you are 60, that risk rises to 1 in 29. No matter how you slice the statistical pie, the fact remains that breast cancer is a serious disease that affects many women.
Why has the incidence of breast cancer risen in this country?
As we have seen, one reason is that the accounting rules of the National Cancer Institute have changed slightly. Other reasons may be nutrition and changes in dietary habits: women who are better nourished often begin to menstruate earlier and thus have a longer exposure to estrogen than women who begin to menstruate at age 15 or 16. Delayed childbearing also increases risk, and women are now marrying later, having fewer children, and having them later. It is also possible that environmental pollutants contribute to breast cancer, though the links have not been firmly established.
Another important reason is that people are living longer, which makes them vulnerable to many kinds of cancer. The population as a whole is aging. From 1970 to 1990, the number of American women who were between 20 and 39 years old rose substantially, leading to an increase in the number of breast cancers diagnosed at those ages. If age-specific breast cancer rates are applied to the female population for 1970, 1980, and 1990, the resulting numbers of breast cancer cases are 5,120, 7,800, and 10,050, respectively. These increasing numbers could give the impression of an epidemic in younger women if the increase in population is not taken into account. The same reasoning can be applied to older groups of women, who are statistically more likely to be diagnosed with breast cancer.
One of the most significant factors is increased detection because of widespread mammography. Breast cancer now is often detected earlier when it is more treatable; though more cases are discovered, fewer women die of the disease. Between 1950 and the late 1980s, the rate of mortality from breast cancer was more or less stable. Between 1990 and 1994, breast cancer mortality declined 5.6 percent, the largest short-term drop in more than forty years.
Then too, more treatment choices have become available. Many women who are diagnosed with breast cancer will not have to have a mastectomy. Instead they will probably face a combination of surgery, radiation, and/or chemotherapy.
Breast cancer is probably the disease women in the United States fear most. Although coronary artery disease is the leading killer of American women, affecting about 2.5 million and killing about 500,000 every year, breast cancer has a more fearful image. Excluding skin cancers, it is the most widespread form of cancer among women in this country and the second most lethal (after lung cancer). According to the American Cancer Society, an estimated 192,000 American women are diagnosed with breast cancer every year and 40,200 die of it. Even when it is not lethal, the consequences of this disease — the possible surgical loss of a breast and the physical and psychological aftereffects — are profoundly disturbing to most women.