Projection of lifetime cancer risk from high-resolution chest CT using the LAR model in Fars Province, Iran, during the COVID-19 pandemic
摘要
The study addresses concerns regarding the potential increase in cancer cases due to the widespread use of high-resolution computed tomography (HRCT) during the COVID-19 pandemic.
MethodIt estimates the Lifetime Attributable Risk (LAR) of certain cancers associated with HRCT in Fars Province, Iran. The estimation is based on a cross-sectional analysis conducted at Namazi Hospital from February 2020 to December 2022. The study employed the Imaging Performance Assessment of CT Scanners (ImPACT) to estimate organ doses. Additionally, it applied the Biological Effects of Ionizing Radiation (BEIR) Committee models to calculate the Lifetime Attributable Risk (LAR) of cancer. A sensitivity analysis was also conducted to project the anticipated increase in radiation-induced cancers in the region.
ResultsOut of 1,411 patients 754 (53.4%) were male, and their ages ranged from 15 to 95 years. 28% (395) had HRCT more than once (2 to 8 times). The mean and 95% uncertainty limits (UL) for total LAR of lung, thyroid, esophagus, stomach, liver, breast and Leukemia were 90 (95% UL, 80 − 116), 24 (95% UL, 18 − 33), 32 (95% UL, 26–39), 9 (95% UL, 8–11), 5 (95% UL, 4–6), 217 (95% UL, 194–244) and 30 ( 95% UL, 10–101) per 100,000 persons, respectively. The excess cancer burdens from radiation in Fars are estimated at approximately 55 years for solid cancers and 58 years for leukemia, with the following rates: lung 1.2%, thyroid 0.8%, breast 0.7%, esophagus 2.8%, stomach 0.1%, liver 0.9%, and leukemia 0.5%.
ConclusionThe widespread use of HRCT during the COVID-19 pandemic, while crucial for diagnosis and management, may increase the risk of radiation-induced cancers, especially among younger individuals and women. Key factors influencing this risk include repeated scans, younger age at exposure, and sex differences. Although the overall cancer burden from HRCT is low compared to baseline cancer incidence, dose optimization and ultra-low-dose protocols are essential to minimize harm.