Tehran University of Medical Sciences Frontiers in Biomedical Technologies 2345-5837 11 1 2023 02 06 69 74 Atefeh Tahmasebzadeh Research Committee, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Reza Paydar Department of Radiation Science, Faculty of Allied Medicine, Iran University of Medical Science, Tehran, Iran Hosein Kaeidi Radiology Assistant, Department of Radiology, Shahid Beheshti University of Medical Science,Tehran,Iran 2022 10 25 2022 11 23 Purpose: Evaluating organ radiation doses and also lifetime risk (LAR) of breast cancer from lung CT scans of 735 female patients from the age of 20-50 with Covid19 surveyed by four Corona center hospitals in Tehran, Iran. Patients’ data and exposure information were extracted from dose report pages in picture archiving and communication systems. Materials and methods: Patients were divided into six age groups 20-25; 25-30; 30-35; 35–40; 40-45 and 45–50 years. Breast, thyroid, lung and heart doses were calculated by NCICT, and LAR of breast cancer incidence has been evaluated by BEIR VII report. Results: The average dose of breast, thyroid, lung and heart were 3.97, 4.75, 4.10 and 3.37 mGy and also the average of the effective dose was 2.56 mSv. Also, the average LAR of breast cancer in female patients was 7.45 per 100,000 exposures and it decreased with age. Conclusion: Although CT scan is a useful instrument in the diagnosis and treatment of Corona disease, but it should be recommended with caution due to the increased risk of breast cancer, especially in younger women. https://fbt.tums.ac.ir/index.php/fbt/article/view/574 https://fbt.tums.ac.ir/index.php/fbt/article/download/574/302