Related Experiment Videos
Medical diagnostic x rays and thyroid cancer
P D Inskip1, A Ekbom, M R Galanti
1Radiation Epidemiology Branch, National Cancer Institute, Bethesda, MD, USA.
Journal of the National Cancer Institute
|November 1, 1995
Summary
Diagnostic x-rays pose a very small risk of thyroid cancer. This study found no significant association between medical diagnostic x-rays and increased thyroid cancer risk, even for early exposures.
Area of Science:
- Medical imaging
- Radiation oncology
- Epidemiology
Background:
- Diagnostic x-rays are the primary source of man-made ionizing radiation exposure for the public.
- The cancer risks associated with diagnostic x-ray exposure remain uncertain.
- Previous studies relied on patient recall, raising concerns about data accuracy.
Purpose of the Study:
- To investigate the association between medical diagnostic x-rays and thyroid cancer risk.
- To utilize prospectively recorded hospital chart data for accurate exposure assessment.
Main Methods:
- A case-control study involving 484 thyroid cancer patients and matched controls from Sweden (1980-1992).
- Information on diagnostic radiography was obtained by searching hospital records.
- Thyroid radiation doses were estimated based on examination type and historical data.
Main Results:
- No increased tendency for thyroid cancer cases to have undergone x-ray procedures associated with higher thyroid radiation doses.
- Analysis restricted to early x-rays (pre-1960) and childhood/adolescent exposures showed no significant association.
- The relative risk of thyroid cancer was not significantly linked to estimated cumulative radiation dose from diagnostic x-rays (P-trend = .80).
Conclusions:
- The risk of developing thyroid cancer from medical diagnostic x-rays is minimal.
- This study provides evidence suggesting a very low cancer risk from diagnostic radiography.