Breast+Neoplasm+Radiation+Etiology Clinical Trial
Official title:
Cancer Risk in X-Ray Technologists
| Verified date | April 2020 |
| Source | National Institutes of Health Clinical Center (CC) |
| Contact | n/a |
| Is FDA regulated | No |
| Health authority | |
| Study type | Observational |
Researchers at the National Cancer Institute and the University of Minnesota have followed a
nationwide cohort of 146,022 radiologic technologists since 1982 (Boice 1992; Doody 1998;
Mohan 2003; Sigurdson 2003). This is one of the largest cohorts of medical radiation workers
studied to date (Yoshinaga 2003)and the only one with substantial numbers of women (73%
female), extensive covariate data, both incident and death outcomes, and estimated
occupational radiation doses. The overall study objectives are to: quantify radiation
dose-response for cancers of the breast, thyroid, and other radiogenic sites; assess cancer
risks associated with genotypic, phenotypic, or other biologically measurable factors; and
determine if genetic variation modifies radiation-related cancer risks.
More than 110,000 technologists completed at least one of three comprehensive questionnaire
surveys administered over the last 20 years and 18,500 are deceased. The First Survey was
mailed during 1984-1989 to 132,454 known living radiologic technologists, of whom 90,305
(68%) completed the survey (Boice 1992). The Second Survey was mailed during 1993-1998 to
126,628 known living technologists, of whom 90,972 (72%) completed the questionnaire
(Sigurdson2003). Both surveys included detailed questions about employment as a radiologic
technologist, family history of cancer, reproductive history, height, weight, other cancer
risk factors (such as alcohol and tobacco use), history of personal diagnostic and
therapeutic medical radiation procedures, and information on cancer and other health
outcomes. A third follow-up of this cohort was recently completed. During 2003-2005, the
Third Survey was mailed or administered by telephone to 101,694 living cohort members who had
completed at least one of the two previous surveys; 73,838 technologists (73%) completed the
survey. This questionnaire elicited information on medical outcomes to assess
radiation-related risks, detailed calendar-specific employment data to refine the
occupational ionizing radiation dose estimates, and behavioral and residential histories for
estimating lifetime ultraviolet (UV) radiation exposures.
The large number of women with estimates of cumulative radiation dose to specific organs
(e.g. breast) (Simon 2006; see Figure 7 and Table 9) offers at are opportunity to study
effects of low-dose radiation exposure on breast and thyroid cancers, the two most sensitive
organ sites for radiation carcinogenesis in women.. We are not aware of any other study
population in which both quantified radiation doses and biospecimens are available for
individuals with protracted low-dose ionizing radiation exposures. Incorporation of
assessment of the role of genetic polymorphisms and molecular variants in DNA repair and
other genetic pathways that may be functionally important in radiation carcinogenesis would
provide initial results on the possible role of genetic factors in the cancer-radiation
relationship. Because large numbers of women are exposed to ubiquitous low-dose radiation
from occupational, medical, and environmental sources, the presence of radiation-sensitive
genetic variants that influence the risk of breast and other cancers would have important
public health implications.
| Status | Completed |
| Enrollment | 146022 |
| Est. completion date | March 31, 2020 |
| Est. primary completion date | March 31, 2020 |
| Accepts healthy volunteers | No |
| Gender | All |
| Age group | 18 Years to 110 Years |
| Eligibility |
- INCLUSION CRITERIA: Medical x-ray technologists certified (at least two years during 1926-1982) by the American Registry of Radiologic Technicians (ARRT). |
| Country | Name | City | State |
|---|---|---|---|
| United States | University of Minnesota | Minneapolis | Minnesota |
| Lead Sponsor | Collaborator |
|---|---|
| National Cancer Institute (NCI) |
United States,
Kitahara CM, Preston DL, Neta G, Little MP, Doody MM, Simon SL, Sigurdson AJ, Alexander BH, Linet MS. Occupational radiation exposure and thyroid cancer incidence in a cohort of U.S. radiologic technologists, 1983-2013. Int J Cancer. 2018 Nov 1;143(9):2145-2149. doi: 10.1002/ijc.31270. Epub 2018 Feb 2. — View Citation
Preston DL, Kitahara CM, Freedman DM, Sigurdson AJ, Simon SL, Little MP, Cahoon EK, Rajaraman P, Miller JS, Alexander BH, Doody MM, Linet MS. Breast cancer risk and protracted low-to-moderate dose occupational radiation exposure in the US Radiologic Technologists Cohort, 1983-2008. Br J Cancer. 2016 Oct 25;115(9):1105-1112. doi: 10.1038/bjc.2016.292. Epub 2016 Sep 13. — View Citation
Simon SL, Preston DL, Linet MS, Miller JS, Sigurdson AJ, Alexander BH, Kwon D, Yoder RC, Bhatti P, Little MP, Rajaraman P, Melo D, Drozdovitch V, Weinstock RM, Doody MM. Radiation organ doses received in a nationwide cohort of U.S. radiologic technologists: methods and findings. Radiat Res. 2014 Nov;182(5):507-28. doi: 10.1667/RR13542.1. Epub 2014 Oct 31. — View Citation
| Type | Measure | Description | Time frame | Safety issue |
|---|---|---|---|---|
| Primary | Ionizing radiation | Occupational ionizing radiation-related risks for cancer and other medical outcomes. | Work history information collected on questionnaires plus badge dose measurements | |
| Secondary | Ultraviolet radiation | Cancer and other disease risks associated with ultraviolet radiation exposure. | Sun exposure information and medical outcomes |