Female breast cancer patients;

Treated with primary surgery for stage I-III invasive adenocarcinoma of the breast or ductal carcinoma in situ (DCIS);

Age between 40-75 years at time of start RT;

WHO performance status 0-1;

Planned for RT alone to the breast, the chest wall and/or the lymph node areas;

Start of RT is between 01-01-2015 and 31-12-2013;

Available planning CT scan and dose distribution;

Adjuvant systemic treatment, including hormonal therapy or chemotherapy is allowed;

Medical history of coronary artery disease and/or myocardial infarction is not an exclusion criterion;

Written informed consent.

Implications of MEDIcal Low Dose RADiation Exposure - BReast Cancer Acute Coronary Events