Researchers have found that exposure to radiation from CT scans is associated with higher risks of developing thyroid cancer and leukemia, but according to health experts here, the probability of CT scans inducing cancers is very minimal. Published in the journal JNCI Cancer Spectrum, the study based on a National Health Insurance dataset in Taiwan between 2000 and 2013 followed 22,853 thyroid cancer, 13,040 leukemia and 20,157 non-Hodgkin lymphoma cases.
Results showed that patients who developed thyroid cancer and leukemia had significantly higher likelihood of having received CT scans.
'The probability of CT scans inducing cancers is very minimal. Very long and prolonged radiation exposure can cause skin redness, but the chance of developing malignancy is extremely less," Gaurav Dixit, Senior Consultant, Clinical Haematologist, Action Cancer Hospital in New Delhi told IANS.
"However we need to be careful in children, and number of scans should be restricted," Dixit added.
The study also revealed that for patients between 36 and 45 years of age, there was a three-fold increased risk of non-Hodgkin lymphoma associated with CT scans.
Patients receiving CT scans had in general marked increases in the risk of developing thyroid cancer and leukemia, especially in female patients and patients younger than 45.
However, according to Nitin Leekha, Senior Consultant, Surgical Oncology, Jaypee Hospital, in Noida, radiation exposure of any kind is associated with cancer and the fact is already well established.
"Radiation exposure with single diagnostic CT is relatively harmless. It takes multiple CT scans for radiation exposure to reach a point where it can lead to cancers. Thyroid cancer is the most commonly associated cancer with radiation exposure among others," Leekha told IANS.
"One should avoid repeated radiation exposure in diagnostic tests unless it is absolutely necessary. There is usually a time lag of years before cancer develops," Leekha stressed.
Leekha added that if a person had radiation exposure multiple times in the childhood they may be at an increased risk of developing cancer.
"Such individuals should visit an oncosurgeon for evaluation," he concluded.