This new study presented at the annual meeting of the Radiological Society of North America, investigated whether screening mammograms increase risk of breast cancer in women with relatively high risk due to a family history of breast cancer. The authors conducted a meta-analysis using data from existing epidemiological studies, mostly focusing on breast cancer mutation carriers (BRCA1 and BRCA2). The analysis incorporated approximately 5,000 women with a median age of 45. As expected, the analysis found an increased risk of breast for these high-risk women due to low-dose radiation exposure (OR =1.63, 95% confidence interval (CI) = 0.92 - 2.90). Exposure before age 20 (OR = 2.0, 95% CI = 1.4 - 3.0) or five or more exposures were also found to be associated with a heightened radiation-induced breast cancer risk (OR=1.95, 95% CI = 1.5 - 2.6). The authors conclude that low-dose radiation increases breast cancer risk among young (including perimenopausal) women with a familial or genetic predisposition.
What to do if you are at high risk
This study helped confirm what has been report previously, namely that the radiation exposure resulting from mammograms can increase the risk of breast cancer. The question for those at high risk (whether because of a family history of breast cancer or for other reasons) is what to do in response to this information. We suggest adopting the following strategy:
- Join a respected cancer center program for high-risk women ahead of any breast cancer diagnosis
- Get a screening mammogram by age 30 or the age recommended by your cancer specialist. It is important to have a clean baseline mammogram for future comparison purposes. A small number of high risk women actually develop breast cancer by age 30 and detecting such cancers early is vitally important
- Order and read all radiological reports and discuss them with your cancer specialist. This will help with the evaluation of the degree of uncertainty in any mammogram reading and how soon it needs to be repeated
- If possible, have an MRI each year without always having a mammogram at the same time. Or consider using a screening schedule alternating mammogram plus sonogram in year one with MRI or sonogram only in year two. Try to have your mammograms performed at a facility that uses digital mammography, which has been shown to involve less radiation than conventional mammography
- Avoid professions such as pilot and flight attendant that involve workplace exposure to radiation and have been found to be associated with increased risk of breast cancer
- Adopt a diet that protects against radiation while also reducing breast cancer risk in general (see below).
The following foods have been found to be radioprotective while at the same time being associated with reduced cancer risk:
- Blueberries
- Celery
- Cranberries
- Flaxseed
- Grape juice, purple
- Grapes, red
- Green tea
- Leeks
- Onions & garlic
- Parsley
- Rhubarb
- Turmeric