One low-dose chest CT scan cannot cause significant human chromosomal DNA damage to a patient.

In a study to measure biologic markers of DNA damage in blood samples taken before and after a chest scan, results showed that patients who received the low-dose CT scan did not have increased numbers of DNA double-strand breaks.

However, those patients who took a single standard-dose chest CT scan had a significant increase in the number of DNA double-strand breaks before and after the scan.

Although the direct connection between CT induced biologic changes and the risk of cancer has not been established, the hypothesis shows that exposure to radiation must be minimized. The low dose amount for chest CT scans should be set to approximately 1.5 mSv.

Therefore, applying a low dose CT for lung cancer screening is justified. The biological approach used in estimating possible cancer risks linked with low dose CT scans represents a substantial advance in the research.

More research is needed to ascertain that there is zero risk with the low dose. Scientists are planning more studies involving a larger number of participants in order to achieve statistical significance.

Until now, there is no established causal link between double-strand breaks in DNA and the risk of cancer. CT scans have shown to be beneficial to many cancer patients. The only challenge posed is in identifying individuals with a genetic predisposition to radiation associated meningioma at low doses of radiation.

Compared to other studies that used single biologic analysis, the current research involving two independent biologic analyses has produced findings that can highly be relied upon. The researchers are not interested in finding out the biological effects of different types of radiological diagnosis, including PET/CT, which will help to establish a better system of managing medial radiation exposure.

The only limitation in the study was the lack of random assignment of CT protocols. The DNA damage was also assessed in peripheral blood lymphocytes. More research is needed to determine if DNA damage is different in solid organ tissues like the lungs.