New research indicates that patients with non-Hodgkin's lymphoma who undergo eight or more CT scans double their risk for secondary cancers.
Researchers from Taipei Veterans General Hospital in Taiwan found that these second cancers generally occurred in areas of the body where CT scan fields overlapped, amounting to double the radiation amount. These areas were where thoracic and abdominal CT scans overlap.
"The incidence of secondary-cancer origin from breast, stomach, and liver is higher in patients with more CT scans," wrote Sheng Hsuan Chien, MD, and colleagues from the Taipei Veterans General Hospital in Taiwan. "These sites are usually located at the interface or overlapping area and receive a double dose of radiation from 2-CT scans procedures."
The team looked at 4874 patients with non-Hodgkin's lymphoma who received curative-intent treatment from January 1997 to December 2010.
Patients had a median of eight CT scans done within one year of their diagnosis.
The risk is dose-dependent; therefore, with each additional CT scan, the risk for a secondary cancer went up by three percent.
"Physicians should assess the timing of CT scans more carefully and avoid [the overuse of] CT scans, especially in those with complete remission and a highly curable population," the researchers conclude.
Source: Medscape