Can X-Ray Radiation Exposure Increase Cancer?

One Expert Says Hazard Greater Than Patients Told, but Another Strongly Disagrees

From the WebMD Archives

Oct. 7, 2004 -- Patients getting chest X-rays, body scans, and other tests involving radiation exposure don't get enough information about the cancer risks, a new report says.

For example, a child receiving a CT scan will have a one in 1,000 cancer death risk, yet this risk of radiation exposure is often not discussed with parents, writes Eugenio Picano, MD, with the Institute of Clinical Physiology, part of the National Research Council in Pisa, Italy.

His commentary appears in this week's British Medical Journal. In the U.S., his statements drew alarm. "It's ludicrous, the most ludicrous thing I've ever heard," Polly Kochan, MD, a pediatric radiologist at Temple Children's Hospital in Philadelphia, tells WebMD. "I would love to know where his numbers came from ... one in 1,000. That is not reasonable."

WebMD was unable to reach Picano for comment.

Getting Signed Consent

In his paper, Picano states that radiologists take different tacks when patients are asked to sign informed consent forms. "Don't say a word" about radiation exposure is the most common approach, justified by time constraints plus "a paternalistic 'expert knows best'" attitude, Picano writes.

Some radiologists choose to understate the risks of radiation exposure, he writes. One nuclear medicine test involves an injection of radioactive material -- which patients might be told is radiation exposure similar to a simple chest X-ray. In reality, however, he says the dose ranges from 50 to 4,000 chest X-rays, depending on the specific nuclear medicine procedure.

"Such imprecise statements are probably intended to reassure patients to avoid useless concern about an unavoidable risk," writes Picano. "However, this attitude of 'one consent fits all' ... may mislead [doctors] to underestimate the associated risks" of radiation exposure.

Kochan balks at Picano's statements.

Especially in examining children, "we are very aware of risks of radiation exposure, we always have been, so we use as little as possible to achieve a diagnostic X-ray," Kochan tells WebMD.

"We give up a little bit of image quality because it's a child," she says. "We use lead shielding over the sex organs. It's something that radiologists all over the country do. We've always been aware of the importance of keeping radiation exposure as minimal as possible, especially with children."

Also, she "talks at great length with the parents, about everything, about how we're going to do this exam, how we make sure the child is not traumatized. That's much more important than any risk from radiation exposure during the exam."

The technology has improved so much, especially the new CT scanners, that radiation exposure is already minimized, she tells WebMD.

And if parents decide against the exam, what then? What's the alternative? What's the risk of not doing the test? These are all questions that should be considered.

Radiologists are known to be conservative in following a doctor's orders for tests, she says. "We have been known to challenge the doctor who orders a study we don't think is indicated. We call them and ask, 'What specifically are you looking for?' We are always considering radiation exposure."

Show Sources

SOURCES: Picano, E. British Medical Journal, Oct. 9, 2004; vol 329: pp 849-851. Polly Kochan, MD, pediatric radiologist, Temple Children's Hospital, Philadelphia.
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