Background: Evidence linking risk of lymphoma and B-cell lymphoma subtypes to ionizing radiation is
inconclusive, particularly at low exposure levels.
Methods: We investigated risk of lymphoma (all subtypes), B-cell lymphomas, and its major subtypes, associated
with low-level occupational exposure to ionizing radiation, in 2346 lymphoma cases and 2463 controls, who
participated in the multicenter EpiLymph case-control study. We developed a job-exposure matrix to estimate
exposure to ionizing radiation, distinguishing between internal and external radiation, and we applied it to the
lifetime occupational history of study subjects, We calculated the Odds Ratio (OR) and its 95% confidence interval
(95% CI) for lymphoma (all subtypes combined), B-cell lymphoma, and its major subtypes using unconditional,
polytomous logistic regression adjusting for age, gender, and education.
Results: We did not observe an association between exposure metrics of external and internal radiation and risk of
lymphoma (all subtypes), nor with B-cell lymphoma, or its major subtypes, at the levels regularly experienced in
occupational settings. An elevated risk of diffuse large B cell lymphoma was observed among the most likely
exposed study subjects with relatively higher exposure intensity, which would be worth further investigation.
Conclusions: Further investigation is warranted on risk of B cell lymphoma subtypes associated with low-level
occupational exposure to external ionizing radiation, and to clarify whether lymphoma should be included among
the cancer outcomes related to ionizing radiation.
Item Type:
Article (Published)
Refereed:
Yes
Additional Information:
Article number: 43
Uncontrolled Keywords:
Ionizing radiation; Lymphoma; Diffuse large B cell lymphoma; Occupational exposure