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 t