Screening mammograms are the gold standard for detecting breast cancer. The paramount benefit of regular screening is finding cancer early at its most treatable stage. There are conflicting recommendations as to what age to begin screening and how often. Some sources recommend that screening begin at age 40 and continue once a year. Others recommend that you should get a baseline mammogram at age 50 and repeat every other year. To make a balanced and informed decision, it is worthwhile to examine not only the benefits but also the risks of breast screenings.
Exposure to Radiation
The average mammogram includes four x-rays. If any suspicious lesions are found, more x-rays are ordered. Radiation from all x-rays is cumulative. A study published by Cornell University examines the role of ionizing radiation and breast cancer. The study involved groups of women who have been exposed to large amounts of radiation including treatments to monitor other cancers, enlarged thymus glands, tuberculosis and scoliosis. The results conclusively found that ionizing radiation can cause breast cancer. For women under the age of 30 who carry the BRCA1 or BRCA2 gene mutation, the danger of radiation-induced breast cancer may outweigh the benefits of mammography, according to a 2009 study reported in the Journal of the National Cancer Institute.
False Positives
Five percent to 15 percent of routine screening mammograms require more testing. Though most of these tests turn out to be normal, follow-up x-rays, ultrasounds and biopsies may be performed. In a study conducted at the University of North Carolina at Chapel Hill, researcher Noel T. Brewer reported that women given false alarms from their mammograms experienced high levels of distress and anxiety.
False Negatives
The National Cancer Institute reports that mammograms miss up to 20 percent of breast cancers, especially in younger women. Younger women tend to have denser breast tissue, which makes cancer more difficult to detect.
Questionable Benefits
In a 2010 report on mammography published in the online edition of the British Medical Journal, study author Dr. Karsten Jorgensen says, "mammography screening is not as good as we hoped years ago. It is questionable if it saves women from dying from breast cancer." Researchers in this study pointed out that one of three breast cancers discovered by a mammogram will most likely regress without any sort of treatment. The study also compared large groups of women in different countries who received screening and those who did not. The results demonstrated that the unscreened women had fewer breast cancer diagnoses than the screened women. Stanford physician and professor Debra Ikeda advises, "women need to know that with routine mammograms, there may be false positives and a need for biopsies, but women should make that choice for themselves, with a doctor's help."
References
- Medline Plus: Mammograms May Not Boost Survival
- American Cancer Society Guidelines for Breast Cancer Screening: Update 2003
- Medical News Today: Stick With Older Mammography Recommendations, Stanford Experts Say
- Cornell University Fact Sheet: Ionizing Radiation and Breast Cancer Risk
- Science Daily: Early Mammograms May Have Net Harm in Some BRCA Mutation Carriers
