Radiation from CT scans causes 29,000 cancers a year, kills 14,500 Americans

Wednesday, April 21, 2010 by: David Gutierrez, staff writer
Tags: CT scans, cancer, health news

(NaturalNews) Computerized tomography (CT) medical scans cause at least 29,000 cases of cancer and 14,500 deaths in the United States every year, according to a study published in the Archives of Internal Medicine.

Shocking as this figure is, a second study published in the same issue and conducted by researchers from the University of California-San Francisco suggests that the reality may actually be much worse.

CT scans are diagnostic tests in which radiation is used to take a cross-sectional picture of a patient's organs. They have become far more common in the United States over the past 30 years, increasing in frequency from 3 million per year in 1980 to the current rate of 70 million per year.

In the first study, researchers from the National Cancer Institute used current estimates of CT scan radiation exposure to calculate the cancer risk produced by the procedure. They found that at current rates of use, the scans kill nearly 15,000 people a year, and cause twice as many cases of cancer. The risks vary by age, with younger patients at much higher risk because they have more time in which a cancer can develop.

The researchers estimated that a three-year-old female receiving an abdominal CT scan has a one in 500 risk of developing cancer as a direct result. The risk decreases to one in 1,000 by age 30 and three in 10,000 by age 70.

The University of California study suggests that these numbers are actually far too low, however. Current estimates of how much radiation exposure a patient receives from a given CT scan are based on old studies that scanned inanimate objects equipped with sensors. The new study actually measured the radiation dose received by 1,119 patients undergoing CT scans at four different hospitals in the San Francisco area.

The researchers found that actual radiation exposure was anywhere from four to 13 times higher than prior studies had suggested.

Rosaleen Parsons of the Fox-Chase Cancer Center suggests that patients keep their medical records to avoid unnecessary repetition of tests, and ask their doctors about alternatives to radiation-based scans.

Sources for this story include: www.usatoday.com; online.wsj.com.