Lifetime attributable risk of cancer incidence and mortality in routine digital radiology procedures

Purpose: Digital radiography has the potential to improve the practice of radiography but it also has the potential to significantly increase patient doses. Considering rapidly growing digital radiography in many centers, concerns rise about increasing the collective dose of the human population and following health effects. This study aimed to estimate organ and effective doses and calculate the lifetime attributable risk (LAR) of cancer incidence and mortality in digital radiography procedures in Iran. Methods: Organ and effective doses of 12 routine digital radiography examinations including the skull, cervical spine, chest, thoracic spine, lumbar spine, pelvic and abdomen were estimated using PCXMC software based on Monte Carlo simulation method. Then, LARs of cancer incidence and mortality were estimated using the BEIR VII method. Results: Organ doses ranged from 0.01 to a maximum of 2.5 mGy while effective doses ranged from 0.01 to 0.7 mSv. Radiation risk showed dependence on the X-ray examination type and the patient's sex and age. In skull and cervical X-rays, the thyroid; in the chest and thoracic spine X-rays, the lung, and breast; and in the lumbar spine, pelvic and abdominal X-rays, the colon and bladder had the highest LAR of cancer incidence and mortality. Furthermore, younger patients and also females were at higher radiation risk. Conclusion: The lifetime attributable risk of cancer incidence and mortality due to radiation exposure is not trivial. Therefore efforts should be made to reduce patient doses while maintaining image quality.