Introduction: Adjuvant radiotherapy reduces the risk of recurrence and death for early-stage breast cancer. However, dose to the heart should be considered since recent data suggest an increasing risk of ischemic heart disease with increasing dose to the heart. Conduction abnormalities have been reported after mediastinal radiation for Hodgkin's disease, but the risk of conduction disorders and arrhythmias does not appear to be increased subsequent to breast cancer radiotherapy. Such conduction abnormalities constitute a quite heterogenous group covering mild as well as severe disorders. Objectives: The aim of this study was to examine the risk of severe conduction abnormalities evaluated by implantation of a pacemaker, subsequent to breast cancer radiotherapy. Methods: From the database of the Danish Breast Cancer Collaborative Group, we identified women treated with radiotherapy for early-stage breast cancer in Denmark from 1982 to 2005. By record linkage to the Danish Pacemaker and ICD Registry information was retrieved on pacemaker implants subsequent to radiotherapy. Rate ratios (RR) of pacemaker implantation for left versus right sided breast cancer were calculated. Results: Among 18,308 women treated with radiotherapy for early-stage breast cancer, 179 women had a pacemaker implanted subsequent to radiotherapy, 90 in 9,315 left sided and 89 in 8,993 right sided breast cancers. The unadjusted RR was 1.02 (0.76-1.36 95% CI, p=0.91) and the RR adjusted for year, age and time since diagnosis was 1.06 (0.79-1.42 95% CI, p=0.71). Conclusions: Adjuvant radiotherapy as practiced in Denmark for early-stage breast cancer does not increase the risk of severe conduction abnormalities in the heart.
|Journal||Supportive Care in Cancer|
|Issue number||SUPPL. 1|
|Publication status||Published - 2015|
|Event||MASCC/ISOO International Symposium - Bella Center, Copenhagen, Denmark|
Duration: 25. Jun 2015 → 27. Jun 2015
|Seminar||MASCC/ISOO International Symposium|
|Period||25/06/2015 → 27/06/2015|