X-Rays Blamed in 1,000 Cancer Cases Annually

Diagnostic X-rays may cause about 1% of all the leukemia and breast cancer in the United States, amounting to about 1,000 extra cancer cases each year, a new study cautions.

Even though the dangers are small, the researchers said both physicians and patients should carefully weigh the benefits and the risks before using X-rays.

No one is sure what, if any, harm low-level radiation causes. But, the researchers wrote, “Until more accurate estimates become available, it seems prudent to use our results as a basis for discussion of the risks and benefits of medical radiography (X-rays), as well as for policy analyses that pertain to efforts at dose reduction.”

The study, directed by Dr. John S. Evans of the Harvard School of Public Health and published in last week’s New England Journal of Medicine, estimated that X-rays cause 267 leukemia cases and 250 leukemia deaths annually. This is about 1% of the 25,000 new cases diagnosed each year.

The researchers further estimated that X-rays cause 788 breast cancer cases and 370 breast cancer deaths yearly, which would make up seven-tenths of 1% of the 119,900 new cases each year.