Estimating cancer induction risk from abdominopelvic scanning with 6-and 16-slice computed tomography

Abstract

Purpose: The biological effects of ionizing radiation (BEIR VII) report estimates that the risk of getting cancer from radiation is increased by about a third from current regulation risk levels. The propose of this study was to estimate cancer induction risk from abdominopelvic computed tomography (CT) scanning of adult patients using 6- and 16-slice CT scanners. Materials and methods: A cross-sectional study on 200 patients with abdominopelvic CT scan in 6 and 16-slice scanners was conducted. The dose-length product (DLP) and volume CT Dose Index (CTDIvol) values from the scanners as well as the effective dose values from the ImPACT CT patient dosimetry calculator with the biological effects of ionizing radiation (BEIR VII) method were used to estimate the cancer induction risk. Results: The mean (and standard deviation) values of CTDIvoi and DLP were 6.9 (+/- 1.07) mGy and 306.44 (+/- 60.57) mGy.cm for 6-slice, and 5.19 (+/- 0.91) mGy and 219.7 (+/- 49.31) mGy.cm for 16-slice scanner, respectively. The range of effective dose in the 6-slice scanner was 2.61-8.15 mSv and, in the 16-slice scanner, it was 1.47-4.72 mSv. The mean and standard deviation values of total cancer induction risk in abdominopelvic examinations were 0.136 +/- 0.059% for men and 0.135 +/- 0.063% for women in the 6-slice CT scanner. The values were 0.126 +/- 0.051% for men and 0.127 +/- 0.056% for women in the 16-slice scanner. Conclusions: The cancer induction risk of abdominopelvic scanning was noticeable. Therefore, radiation dose should be minimized by optimizing the protocols and applying appropriate methods.