C Wadsten1,2,3, A-K Wennstig4,5,6, H Garmo7,8, Greger Nilsson9,10,11, Carl Blomqvist12,13, Lars Holmberg4,8, Irma Fredriksson14,15, F Wärnberg4, M Sund16. 1. Department of Surgery and Perioperative Sciences, Umeå University, Umeå, Sweden. charlotta.wadsten@rvn.se. 2. Department of Surgical Sciences, Uppsala University, Uppsala, Sweden. charlotta.wadsten@rvn.se. 3. Department of Surgery, Sundsvall Hospital, Sundsvall, Sweden. charlotta.wadsten@rvn.se. 4. Department of Surgical Sciences, Uppsala University, Uppsala, Sweden. 5. Department of Surgery, Sundsvall Hospital, Sundsvall, Sweden. 6. Department of Oncology, Sundsvall Hospital, Sundsvall, Sweden. 7. Regional Cancer Center, Uppsala University/Uppsala University Hospital, Uppsala, Sweden. 8. Faculty of Life Sciences & Medicine, Section of Cancer Epidemiology & Population Health, King's College, London, UK. 9. Department of Immunology, Genetics and Pathology, Section of Experimental and Clinical Oncology, University Hospital, Uppsala University, Uppsala, Sweden. 10. Department of Oncology, Gävle Hospital, Gävle, Sweden. 11. Department of Oncology, Visby Hospital, Visby, Sweden. 12. Department of Oncology, Örebro University Hospital, Örebro, Sweden. 13. Department of Oncology, Helsinki University Hospital, Helsinki, Finland. 14. Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden. 15. Department of Breast and Endocrine Surgery, Karolinska University Hospital, Stockholm, Sweden. 16. Department of Surgery and Perioperative Sciences, Umeå University, Umeå, Sweden.
Abstract
PURPOSE: The use of adjuvant radiotherapy (RT) in the management of ductal carcinoma in situ (DCIS) is increasing. Left-sided breast irradiation may involve exposure of the heart to ionising radiation, increasing the risk of ischemic heart disease (IHD). We examined the incidence of IHD in a population-based cohort of women with DCIS. METHODS: The Breast Cancer DataBase Sweden (BCBase) cohort includes women registered with invasive and in situ breast cancers 1992-2012 and age-matched women without a history of breast cancer. In this analysis, 6270 women with DCIS and a comparison cohort of 31,257 women were included. Through linkage with population-based registers, data on comorbidity, socioeconomic status and incidence of IHD was obtained. Hazard ratios (HR) for IHD with 95% confidence intervals (CI) were analysed. RESULTS: Median follow-up time was 8.8 years. The risk of IHD was not increased for women with DCIS versus women in the comparison cohort (HR 0.93; 95% CI 0.82-1.06), after treatment with radiotherapy versus surgery alone (HR 0.77; 95% CI 0.60-0.98) or when analysing RT by laterality (HR 0.85; 95% CI 0.53-1.37 for left-sided versus right-sided RT). CONCLUSIONS: The risk of IHD was lower for women with DCIS allocated to RT compared to non-irradiated women and to the comparison cohort, probably due to patient selection. Comparison of RT by laterality did not show any over-risk for irradiation of the left breast.
PURPOSE: The use of adjuvant radiotherapy (RT) in the management of ductal carcinoma in situ (DCIS) is increasing. Left-sided breast irradiation may involve exposure of the heart to ionising radiation, increasing the risk of ischemic heart disease (IHD). We examined the incidence of IHD in a population-based cohort of women with DCIS. METHODS: The Breast Cancer DataBase Sweden (BCBase) cohort includes women registered with invasive and in situ breast cancers 1992-2012 and age-matched women without a history of breast cancer. In this analysis, 6270 women with DCIS and a comparison cohort of 31,257 women were included. Through linkage with population-based registers, data on comorbidity, socioeconomic status and incidence of IHD was obtained. Hazard ratios (HR) for IHD with 95% confidence intervals (CI) were analysed. RESULTS: Median follow-up time was 8.8 years. The risk of IHD was not increased for women with DCIS versus women in the comparison cohort (HR 0.93; 95% CI 0.82-1.06), after treatment with radiotherapy versus surgery alone (HR 0.77; 95% CI 0.60-0.98) or when analysing RT by laterality (HR 0.85; 95% CI 0.53-1.37 for left-sided versus right-sided RT). CONCLUSIONS: The risk of IHD was lower for women with DCIS allocated to RT compared to non-irradiated women and to the comparison cohort, probably due to patient selection. Comparison of RT by laterality did not show any over-risk for irradiation of the left breast.
Entities:
Keywords:
Ductal carcinoma in situ; Ischemic heart disease; Radiotherapy
Authors: Anna Plym; Anna L V Johansson; Hannah Bower; Anna-Karin Wennstig; Irma Fredriksson; Johan Ahlgren; Mats Lambe Journal: Breast Cancer Res Treat Date: 2020-06-06 Impact factor: 4.872