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Radiation exposure from CT scans in childhood and subsequent risk of leukaemia and brain tumours: a retrospective cohort study
Mark S Pearce
The Lancet, Early Online Publication, 7 June 2012
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2812%2960815-0/abstract
Findings
During follow-up, 74 of 178 604 patients were diagnosed with leukaemia and 135 of 176 587 patients were diagnosed with brain tumours. We noted a positive association between radiation dose from CT scans and leukaemia (excess relative risk [ERR] per mGy 0.036, 95% CI 0.005â0.120; p=0.0097) and brain tumours (0.023, 0.010â0.049; p<0.0001). Compared with patients who received a dose of less than 5 mGy, the relative risk of leukaemia for patients who received a cumulative dose of at least 30 mGy (mean dose 51.13 mGy) was 3.18 (95% CI 1.46â6.94) and the relative risk of brain cancer for patients who received a cumulative dose of 50â74 mGy (mean dose 60.42 mGy) was 2.82 (1.33â6.03).
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