"Highlights

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  Occupational ionizing radiation may increase breast cancer risk in female physicians.

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  Systematic review and meta-analysis included six observational studies.

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  34,744 participants: 8,103 exposed, 26,641 controls, ≥10 years follow-up.

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  Meta-analysis showed increased breast cancer risk (OR 1.84, 95% CI 1.11–3.06) among female physicians."