K R Burton1,2, A L Park3, M Fralick4, J G Ray2,3,4,5. 1. Department of Medical Imaging, University of Toronto, Toronto, ON, Canada. 2. Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada. 3. Institute for Clinical Evaluative Sciences, Toronto, ON, Canada. 4. Department of Medicine, University of Toronto, Toronto, ON, Canada. 5. Department of Obstetrics and Gynaecology, St. Michael's Hospital, Toronto, ON, Canada.
Abstract
Essentials Tests for pulmonary embolism expose women to low-dose radiation. 5859 pregnancies had a thoracic computed tomography (T-CT) vs. 1.3 million who did not. The adjusted hazard ratio for breast cancer was 1.17 (95% confidence interval 0.80-1.70). The long-term risk of breast cancer among women who had a T-CT remains unknown. SUMMARY: Background The risk of breast cancer may be higher with direct exposure to ionizing radiation from thoracic computed tomography (CT) during pregnancy or the postpartum. We evaluated the short-term risk of maternal breast cancer after exposure to thoracic CT during these periods. Methods We completed a retrospective population-based cohort study of all deliveries between 1995 and 2014 using universal healthcare databases in the province of Ontario, Canada. The main exposure was thoracic CT in pregnancy or ≤ 42 days postpartum. The passive exposure was ventilation-perfusion scintigraphy (VQ) scan in pregnancy or ≤ 42 days postpartum. Each was compared to pregnancies unexposed to thoracic CT or VQ scan. The primary study outcome was newly diagnosed breast cancer starting 366 days post-index delivery date. Results A total of 5859 pregnancies were exposed to thoracic CT, 4075 to VQ scan and 1 292 059 to neither. Starting from 1 year after the index delivery, the median duration of follow-up was 5.9, 7.3 and 11.1 years, respectively. A total of 10 129 women were diagnosed with breast cancer, of whom 9039 (89.2%) were aged ≤ 50 years. There were 27 new cases of breast cancer (7.1 per 10 000 person-years) following thoracic CT vs. 10 080 (7.0 per 10 000 person-years) among the unexposed, an adjusted hazard ratio (HR) of 1.17 (95% confidence interval [CI], 0.80-1.70). Following VQ scan exposure, the incidence rate of breast cancer was 7.0 per 10 000 person-years, an adjusted HR of 1.23 (95% CI 0.81-1.87), compared with the unexposed cohort. Conclusion Exposure to thoracic CT during pregnancy or the postpartum was not associated with an increased short-term risk of maternal breast cancer. The long-term risk should be studied.
Essentials Tests for pulmonary embolism expose women to low-dose radiation. 5859 pregnancies had a thoracic computed tomography (T-CT) vs. 1.3 million who did not. The adjusted hazard ratio for breast cancer was 1.17 (95% confidence interval 0.80-1.70). The long-term risk of breast cancer among women who had a T-CT remains unknown. SUMMARY: Background The risk of breast cancer may be higher with direct exposure to ionizing radiation from thoracic computed tomography (CT) during pregnancy or the postpartum. We evaluated the short-term risk of maternal breast cancer after exposure to thoracic CT during these periods. Methods We completed a retrospective population-based cohort study of all deliveries between 1995 and 2014 using universal healthcare databases in the province of Ontario, Canada. The main exposure was thoracic CT in pregnancy or ≤ 42 days postpartum. The passive exposure was ventilation-perfusion scintigraphy (VQ) scan in pregnancy or ≤ 42 days postpartum. Each was compared to pregnancies unexposed to thoracic CT or VQ scan. The primary study outcome was newly diagnosed breast cancer starting 366 days post-index delivery date. Results A total of 5859 pregnancies were exposed to thoracic CT, 4075 to VQ scan and 1 292 059 to neither. Starting from 1 year after the index delivery, the median duration of follow-up was 5.9, 7.3 and 11.1 years, respectively. A total of 10 129 women were diagnosed with breast cancer, of whom 9039 (89.2%) were aged ≤ 50 years. There were 27 new cases of breast cancer (7.1 per 10 000 person-years) following thoracic CT vs. 10 080 (7.0 per 10 000 person-years) among the unexposed, an adjusted hazard ratio (HR) of 1.17 (95% confidence interval [CI], 0.80-1.70). Following VQ scan exposure, the incidence rate of breast cancer was 7.0 per 10 000 person-years, an adjusted HR of 1.23 (95% CI 0.81-1.87), compared with the unexposed cohort. Conclusion Exposure to thoracic CT during pregnancy or the postpartum was not associated with an increased short-term risk of maternal breast cancer. The long-term risk should be studied.
Authors: Sarah Morton; Holly Lamont; Natalie Silvey; Thomas Browning; Michelle Hayes; Richard Keays; Linsey Christie; Roger Davies; Suveer Singh; Chris Lockie; Alice Sisson; Marcela Vizcaychipi Journal: J Intensive Care Soc Date: 2020-08-26
Authors: Cécile Tromeur; Liselotte M van der Pol; Pierre-Yves Le Roux; Yvonne Ende-Verhaar; Pierre-Yves Salaun; Christophe Leroyer; Francis Couturaud; Lucia J M Kroft; Menno V Huisman; Frederikus A Klok Journal: Haematologica Date: 2018-08-16 Impact factor: 9.941
Authors: Malia S Q Murphy; Deshayne B Fell; Ann E Sprague; Daniel J Corsi; Shelley Dougan; Sandra I Dunn; Vivian Holmberg; Tianhua Huang; Moya Johnson; Michael Kotuba; Lise Bisnaire; Pranesh Chakraborty; Susan Richardson; Mari Teitelbaum; Mark C Walker Journal: Int J Epidemiol Date: 2021-11-10 Impact factor: 7.196