RadRAT: a radiation risk assessment tool for lifetime cancer risk projection

Abstract

Risk projection methods allow for timely assessment of the potential magnitude of radiation-related cancer risks following low-dose radiation exposures. To estimate such risks directly through observational studies would generally require infeasibly large studies and long-term follow-up to achieve reasonable statistical power. We developed an online radiation risk assessment tool (RadRAT) which can be used to estimate the lifetime risk of radiation-related cancer with uncertainty intervals following a user-specified exposure history (https://irep.nci.nih.gov/radrat). The uncertainty intervals are a key component of the program because of the various assumptions that are involved in such calculations. The risk models used in RadRAT are broadly based on those developed by the BEIR VII committee for estimating lifetime risk following low-dose radiation exposure to the U.S. population for eleven site-specific cancers. We developed new risk models for seven additional cancer sites: oral, esophagus, gallbladder, pancreas, rectum, kidney and brain/central nervous system (CNS) cancers using data from the Japanese atomic bomb survivors. The lifetime risk estimates are slightly higher for RadRAT than for BEIR VII across all exposure ages mostly because the weighting of the excess relative risk and excess absolute risk models was conducted on an arithmetic rather than a logarithmic scale. The calculator can be used to estimate lifetime cancer risk from both uniform and non-uniform doses that are acute or chronic. It is most appropriate for low-LET radiation doses <1Gy, and for individuals with life-expectancy and cancer rates similar to the general population in the U.S.

Biokinetics, dosimetry, and radiation risk in infants after 99mTc-MAG3 scans

“…The risk estimation was performed individually for all 20 pediatric patients with RadRAT, published by the US ; exposure year; organs like brain, breast (females), colon, gallbladder, liver, lungs, ovaries (females), kidneys, pancreas, red bone marrow, stomach, thyroid, urinary bladder, uterus (females); exposure rate (acute); dose distribution type (fixed value); organ-specific absorbed doses [10]. The result was the percentage risk in 100,000 persons for the development of stochastic radiation-induced effects for "lifetime attributable risk" and "future risk".…”

“…The lifetime attributable risk (LAR) estimates the probability of cancer development and death by an individual arising from radiation exposure. The future risk is defined as the risk estimated for an individual from the present time until the end of the expected lifetime for developing cancer [6,10].…”

“…A newly developed tool for individual patient risk estimation is the Radiation Risk Assessment Tool (RadRAT) developed by the National Cancer Institute's Division of Cancer Epidemiology and Genetics [10]. This online platform tool was developed based on BEIR VII from the National Academy concerning radiation health effects named Health Risks from Exposure to Low Levels of Ionizing Radiation.…”

“…This online platform tool was developed based on BEIR VII from the National Academy concerning radiation health effects named Health Risks from Exposure to Low Levels of Ionizing Radiation. Utilizing the RadRAT calculator, it is possible to perform lifetime attributable risk (LAR) estimations of radiation-related cancer induction for low-level ionizing radiation with doses < 1 Gy for individuals based on their age, gender, year of exposure, uniform and/or nonuniform doses and organ-specific absorbed doses [10].…”

Radiation risk of breast screening in England with digital mammography

“…In this work, the EAR model used by ICRP 103 has been used. Analyzing the same data using the EAR model by Berrington de Gonzalez et al 41 instead (adaptations of the BEIR VII model) caused no change to the ratio of lives saved owing to screening to the lives lost owing to radiation-induced breast cancers. A larger difference would be expected if an ERR model were to be used instead of an EAR model.…”