Screening Mammography and Radiation Exposure

Last Modified: November 13, 2005


Dear OncoLink "Ask The Experts,"
My mother was diagnosed with breast cancer at 44 years old. As a result of this, I have been having routine mammograms annually since age 30 (I am currently 37). Am I doing more harm than good by doing this in terms of the long-term radiation exposure? Thank you.


Lawrence J. Solin, MD, FACR, Professor of Radiation Oncology at the University of Pennsylvania, responds:

Routine screening for the early detection of breast cancer in the asymptomatic patient includes three components: 1) monthly breast self- examination by the patient, 2) physical examination once or twice yearly by a physician, and 3) bilateral mammography. Screening mammography is typically started at age 40, but can be considered at a younger age for the high-risk patient, typically one who has a strongly positive family history or proven genetic risk from a BRCA1 or BRCA2 gene mutation. The age at which mammographic screening is started is a decision that must be based on the potential risk in the individual patient, in order to maximize the risk-benefit ratio. The potential for radiation to induce a malignancy secondary to mammographic screening is very small, and is typically far outweighed by the potential benefit of early detection of a breast malignancy.

Early detection in the high-risk patient may be improved through the use of alternative imaging modalities, in particular, magnetic resonance imaging (MRI) of the breast. MRI is a method of imaging the breast that does not involve radiation, and is used in conjunction with mammography for imaging the breast. Early studies suggest that MRI may increase the yield for detecting early breast cancer in the high-risk patient. When indicated, MRI should be used in addition to, not instead of, screening mammography.