Radiation Risks of Computed Tomography: Estimating Cancer Incidence from Diagnostic Imaging

Anil Khatak; Santosh Kumar; Md Muzakkir Alam; Sarbari Saha; Anshvi Verma; Shubham Sharma; Dhananjay Kumar Singh

doi:10.29284/c73pdt69

Authors

Anil Khatak Assistant Professor, Department of Allied Health Sciences, Guru Jambheshwar University of Science & Technology, Hisar, Haryana, India
Santosh Kumar Assistant Professor, Department of Vocational Studies & Skill Development (School of Science), Maulana Azad National Urdu University, Gachibowli, Hyderabad, India
Md Muzakkir Alam Assistant Professor, Department of Radio-Diagnosis & Imaging Technology, Al-Karim University, Katihar, Bihar, India
Sarbari Saha Assistant Professor, Department of Medical Radio-diagnosis and Imaging Technology, School of Allied Health Sciences, Noida International University, Noida, Uttar Pradesh, India
Anshvi Verma Research Scholar, Department of Radiological Imaging Techniques (RIT), College of Paramedical Sciences, Teerthanker Mahaveer University, Moradabad, Uttar Pradesh, India
Shubham Sharma Assistant Professor, Department of Radiological Imaging Techniques (RIT), College of Paramedical Sciences, Teerthanker Mahaveer University, Moradabad, Uttar Pradesh, India
Dhananjay Kumar Singh Associate Professor, Department of Radiology, Galgotias University, Greater Noida, Uttar Pradesh, India

DOI:

https://doi.org/10.29284/c73pdt69

Keywords:

Computed tomography, radiation risk, cancer incidence, BEIR VII, low-dose CT, patient safety.

Abstract

Background: Computed tomography (CT) is an essential diagnostic imaging modality in modern medicine; however, it exposes patients to ionising radiation, which carries a measurable long-term risk of radiation-induced malignancy. With the increasing global use of CT, particularly for chest and abdominal imaging, quantifying radiation exposure and associated cancer risk has become a critical public health concern.

Objective: This study aimed to evaluate radiation dose exposure and estimate the lifetime cancer risk attributable to diagnostic CT examinations in a real-world clinical cohort using established risk models.

Materials and Methods: A retrospective analysis was conducted on 500 adult patients who underwent head, chest, or abdominal CT examinations between 2019 and 2023 at a tertiary care hospital. Effective radiation doses were calculated using dose–length product (DLP) conversion factors. Lifetime attributable cancer risk was estimated using the Biological Effects of Ionising Radiation VII (BEIR VII) models, accounting for age, sex, and examination type.

Results: The mean effective dose per patient was 8.7 mSv, with abdominal CT delivering the highest mean dose (12.8 ± 3.5 mSv), followed by chest CT (10.2 ± 2.1 mSv) and head CT (2.1 ± 0.6 mSv). The total collective dose for the cohort was approximately 4.6 Sv. Based on BEIR VII risk estimates, CT-related radiation exposure was projected to result in approximately 4–5 excess lifetime cancer cases and 2–3 cancer-related deaths per 500 patients. Higher projected risks were observed in females, younger patients, and individuals undergoing repeated CT examinations.

Conclusion: Although the individual cancer risk associated with CT imaging is low, the cumulative population-level risk is clinically significant. Abdominal and chest CT examinations contribute disproportionately to radiation burden and projected cancer incidence. These findings emphasise the importance of strict justification of CT use, adherence to ALARA principles, optimisation of scan protocols, and expanded implementation of low-dose CT techniques to ensure patient safety while preserving diagnostic efficacy.

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