2% of cancers due to CT scans

A study by two researchers from the Columbia University’s Center for Radiological Research in New York which was recently published in the New England Journal of Medicine (NEJM) has raised concerns regarding the increasing radiation exposure through Computed Tomography or CT scans.

CT scans provide a three-dimensional (3-D) view of organs and other parts in the human body. This more sophisticated imaging technology was first introduced in the 1970s and its use has increased rapidly, notably in countries like the United States and Japan.

In the United States, it has now been estimated that more than 62 million CT scans are carried out each year, including at least 4 million for children. This is compared to just 3 million scans carried out more than 20 years ago, in 1980. The largest increases in CT scan use are reported to be in the categories of paediatric diagnosis and adult screening, and these trends are expected to continue over the next few years.

The increase in CT scan use in children is said to be driven primarily by the decrease in the time taken to perform such a scan, largely eliminating the need to keep a child stationary by use of drugs or other means.

The Columbia University researchers refer to previous estimates that a third of all CT scans performed in the United States (US) could be replaced with less risky diagnostic technologies or not performed at all. If these estimates are accurate, it would mean that at least 20 million adults and more than 1 million children in the US are being irradiated unnecessarily each year.

The researchers go on to suggest, that in the future, as many as 2% of all cancers in their country may be due to the radiation from CT scans performed presently.

Children are said to be at greater risk than adults from a given dose of radiation because they are essentially more radio-sensitive, and also, because they have more years of life during which a radiation-induced cancer could develop.

Over the past years, CAP has already been raising concerns about the problem of unnecessary tests and the overuse of medical technology, including the repeated use of imaging techniques involving radiation. These overseas findings should sound a warning bell and serve as a prompt for precautionary action.

CAP calls on the Ministry of Health to initiate an urgent review of the use of CT scans, with the aim of restricting patients’ exposure to radiation.

Read how you can be an informed patient and protect yourself against medical errors in the CAP Guide, Can Doctors Be Trusted?