A recent study conducted over a period of 30 years in Sweden has shown that mammograms can reduce deaths from breast cancer by at least 30%. Previous studies indicate that mammograms can prevent one death for every 1,000-1,500 women screened, but these new results are much lower – one death prevented for every 414-519 women screened.
Researchers are also saying that these results may actually underestimate the value of mammograms due to the radical advances in technology in recent years. New digital mammography imaging is much more sensitive than a traditional mammogram and can help aid in earlier detection.
The new study does not address the controversy surrounding the value of screening women in their 40s or how frequently a woman should have a mammogram, but in the US annual mammograms are generally recommended. The American Cancer Society, for example, recommends a mammogram every year starting at 40, the National Cancer Institute recommends the test every one to two years starting at 40, and the American College of Obstetricians and Gynecologists recommends a test every one to two years for women in their 40s and every year for those over 50. In this Swedish study, the women were screened less frequently: every 24 months for women aged 40 to 49, and every 33 months for older women.
Mammography has taken quite a hit in recent years as family doctors, ob-gyns and others that might recommend mammography have been confused about the long-term value of screening. Additionally, mammograms can cause women anxiety, false alarms, and sometimes unnecessary procedures.
This evidence confirms that mammography saves lives, but doesn’t answer the more controversial question of how often women should be screened. Perhaps as the screening becomes more and more effective, they might reduce the pressure to extend the period between mammograms and to limit the tests for younger women.
If you have questions about when you are due for your next appointment, we recommend calling and asking your primary care physician.