Is exposure to radiation from mammograms dangerous?

Website design By BotEap.comThe current recommendation is annual screening mammography starting at age 40. It is a well-known fact that screening for asymptomatic women has been credited for decreasing mortality from breast cancer. Breast cancer is the most common form of cancer in women and the second leading cause of cancer death in American women. In 2009, it was estimated that approximately 194,280 patients were diagnosed with invasive breast cancer and 62,280 with carcinoma in situ. It is estimated that 40,610 have died from this disease. For an average-risk woman, the lifetime incidence of breast cancer is one in seven or 14%.

Website design By BotEap.comHowever, many women are hesitant to have a mammogram due to recent publicity of the link between radiation exposure and an overall increased risk of cancer. This risk must be put into perspective. Humans are routinely exposed to radiation from natural sources, such as radon and cosmic rays from space, food, and water. Living at a higher altitude results in more radiation, as well as frequent air travel. Furthermore, even our own bodies normally contain small amounts of naturally occurring radioactive elements, such as certain isotopes of potassium.

Website design By BotEap.comThe average annual exposure to radiation from natural and man-made sources for a person living in the United States is approximately 500 millirem or 5 mSv (milliSievert). Below is a rough estimate of the radiation dose involved in common diagnostic procedures: chest X-ray – 0.1 mSv, mammography – 0.4 mSv, head CT – 2 mSv, chest CT 7 mSv, abdomen CT 8 mSv, Pelvic CT 6 mSv, chest CT angiogram for pulmonary embolism diagnosis – 15 mSv, coronary angiogram or cardiac catheterization – 15 mSv and PET scan – 8 mSv. Therefore, the amount of radiation associated with a mammogram is approximately 10% of the commonly accepted annual exposure dose.

Website design By BotEap.comThe National Academies of Sciences and the International Commission on Radiological Protection estimate an increase in the incidence of cancer from a new cancer for every 1000 people exposed to 10 mSv. For example, a patient has a CT scan and is exposed to 10 mSv. That person’s lifetime cancer risk attributed to the scan would be 1 in 1,000 or 0.1%. By comparison, your lifetime risk of developing any cancer is 1 in 2.5 or 40%. Therefore, the risk of radiation exposure must be weighed against the medical necessity of the x-ray itself. In my opinion, the benefit of detecting curable breast cancer early with annual mammograms clearly outweighs the very small and remote risk of radiation exposure.