Cancer Panel Says Mammography May Not Prevent Breast Cancer Deaths, U.S. Government Adhere to Screening Guidelines (dateline March 7, 2002)
An announcement by a scientific board at the National Cancer Institute (NCI) in January 2002 has raised questions about the benefits of mammography in helping to prevent breast cancer deaths. Cancer organizations have encouraged women in their forties to begin receiving screening mammograms based on studies from the 1970s and 1980s that showed that mammography could save womens lives by detecting the cancer early. However, the scientific panel argued that those studies were flawed. Yet, in statement issued on February 21, U.S. government health officials said there is sufficient evidence that receiving mammograms every one to two years is effective for women in their forties.
Mammography is a special type of x-ray imaging that uses low dose x-rays with high contrast to create detailed images of the breast. Mammography is currently the only exam approved by the U.S. Food and Drug Administration (FDA) to screen for breast cancer in women who do not show any signs or symptoms of the disease, such as a breast lump. For the last several years, the National Cancer Institute has recommended that all women 40 years of age and older begin receiving annual screening mammograms every one to two years, and then every year beginning at age 50. Other cancer groups recommend that women begin yearly screening mammograms at age 40.
The argument for mammography is based on the following logic: mammography helps detect breast cancer in very early stages. The earlier that breast cancer is detected, the more likely it can be successful treated and the patient will survive. Therefore, routine screening mammograms save lives. This logic is based on past studies from the 1970s and 1980s, which have shown that routine mammograms can reduce breast cancer deaths by 30%.
However, an independent scientific panel (called the PDQ, Physician Data Query), which advises the National Cancer Institute, recently announced that the past studies that showed mammography prevents deaths were flawed. Instead the panel argued that there is insufficient evidence to say whether mammography really saves womens lives.
The panel, which is made up of physicians and cancer experts, admitted that their findings will cause confusion for the over 30 million American women who have annual screening mammograms. Furthermore, the panels announcement contradicted the NCIs current mammography recommendations and the information on its website that says that mammography prevents deaths from breast cancer.
Dr. Peter Greenwald, Director of Cancer Screening at the National Cancer Institute, believes that early detection plays an important role in controlling cancer, which is why the NCI recommends beginning screening mammography at age 40. Dr. Greenwald says that the debate over mammography has nothing to do with its ability to detect breast cancer. Mammography has been proven to find cancer in its very earliest stages. However, the debate lies in whether treating these very small cancers actually prevents deaths from breast cancer or merely results in the overtreatment of tumors that may not ever progress into life-threatening cancers.
On February 21, 2002 Health and Human Services Secretary Tommy Thompson announced that the NCI is not changing its recommendations on mammography. The decision comes after the U.S. Preventive Services Task Force reviewed eight studies of mammography. The task force concluded that mammography can reduce breast cancer deaths by 20% in a 10 year period.
According to the American Cancer Society (ACS), while the number of breast cancer cases continues to rise, breast cancer deaths have decreased significantly over the last 10 years. The ACS attributes this decline in deaths to improved screening and treatment for breast cancer.