Children are at risk of cancer due to CT diaknostics

Thousands of kids get cancer from CT scan

11/06/2013

Terrifying findings were found in a US study on the use of computed tomography (CT) in children and adolescents. According to the scientists, approximately 5,000 cancers result from CT examinations every year in the United States, and paediatricians can counteract this with simple means. A combination of two methods could reduce the number of cancers by around 60 percent.

Computed tomography: advantages and disadvantages of modern radiography
The computed tomogram quickly provides valuable information about a patient's injuries and illnesses, including fractures and bleeding. Especially in accident medicine, the futuristic-looking tubes are therefore often the method of choice. Lying, the patient is pushed into the computer tomograph and examined by radioactive radiation from different perspectives. A computer then calculates cross-sectional images of the human body from the individual images. A regular exam rarely takes longer than ten minutes.

The radiation exposure of an X-ray are aware of patients but also doctors, but the same is obviously not true for computed tomography - which consists essentially of many individual X-rays. The comprehensive insight on the part of the radiologists therefore has direct disadvantages for patients, specifically a 100- to 500-fold higher radiation exposure. In particular, children are at risk, warn now scientists from the University of California to Diana Miglioretti from the Department of Public Health Science.

Cancer danger threatens especially children
For the study of US scientists CT scans were evaluated in children under 15 years. The dose of radioactive radiation was also evaluated locally in 744 cases. The first realization: „The use of computed tomography in children younger than five years has doubled between 1996 and 2005, and even tripled for children from five to 14 years.“ What is reassuring, however, is that the numbers initially remain constant in the following years, and eventually even fall off. Apparently there is now a rethinking.

„The likelihood of getting cancer is higher for younger patients and girls than for older patients and boys“, explain the US scientists. In addition to the lower radiation tolerance, this is mainly due to the remaining lifespan, which allows an accumulation of mutations in the genome of the cell. Depending on the age, the scientists predict that girls „a serious cancer for all 300 to 390 CT examinations of the abdomen, all 330 to 480 examinations of the breast and all 270 and 800 examinations of the spine.“ The 4 million CT scans per year are estimated to result in 4870 cancers.

Fewer CT examinations reduce cancer
However, the number of cancers could be greatly reduced, explain the researchers. If in the future unnecessary CT examinations are avoided, a reduction of about one third is possible. If, in addition, the radiation dose used were to be minimized, the number of cancers could be reduced by about 43 percent. A combination of both methods would avoid about 60 percent of the tumors.

Pediatric radiology Wolfgang Hiersch calms meanwhile: In this country a CT examination would be used much less frequently, he explains. In the US, only a few years have seen a slow rethink. There, for example, appendicitis is still diagnosed by CT as standard in children, whereas ultrasound examinations have long since been used in this country. "However, doctors still have to ask themselves whether a scan by computed tomography is necessary. University of Bochum emphasizes: "Despite this basically positive situation, we also have a tendency to use CT more because of its superior image quality and speed in children." (Lb)

Picture: by-sassi