Radiation dose and cancer risks from radiation exposure during abdominopelvic computed tomography (CT) scans: comparison of diagnostic and radiotherapy treatment planning CT scans

In the present study, radiation doses and cancer risks resulting from abdominopelvic radiotherapy planning computed tomography (RP-CT) and abdominopelvic diagnostic CT (DG-CT) examinations are compared. Two groups of patients who underwent abdominopelvic CT scans with RP-CT (n = 50) and DG-CT (n = 50) voluntarily participated in this study. The two groups of patients had approximately similar demographic features including mass, height, body mass index, sex, and age. Radiation dose parameters included CTDIvol, dose-length product, scan length, effective tube current, and pitch factor, all taken from the CT scanner console. The ImPACT software was used to calculate the patient-specific radiation doses. The risks of cancer incidence and mortality were estimated based on the BEIR VII report of the US National Research Council. In the RP-CT group, the mean +/- standard deviation of cancer incidence risk for all cancers, leukemia, and all solid cancers was 621.58 +/- 214.76, 101.59 +/- 27.15, and 516.60 +/- 189.01 cancers per 100,000 individuals, respectively, for male patients. For female patients, the corresponding risks were 742.71 +/- 292.35, 74.26 +/- 20.26, and 667.03 +/- 275.67 cancers per 100,000 individuals, respectively. In contrast, for DG-CT cancer incidence risks were 470.22 +/- 170.07, 78.23 +/- 18.22, and 390.25 +/- 152.82 cancers per 100,000 individuals for male patients, while they were 638.65 +/- 232.93, 62.14 +/- 13.74, and 575.73 +/- 221.21 cancers per 100,000 individuals for female patients. Cancer incidence and mortality risks were greater for RP-CT than for DG-CT scans. It is concluded that the various protocols of abdominopelvic CT scans, especially the RP-CT scans, should be optimized with respect to the radiation doses associated with these scans.

Automated summary

This study compared radiation doses and cancer risks between abdominopelvic radiotherapy planning computed tomography (RP-CT) and abdominopelvic diagnostic CT (DG-CT) scans. Results showed that RP-CT scans had higher cancer incidence and mortality risks compared to DG-CT scans. It suggests the need to optimize protocols, especially for RP-CT scans, regarding radiation doses.