Implementation
CSIS
In this study, information on adjuvant RT and low-dose tamoxifen following BCS after randomization will be provided to participants who meet the inclusion criteria at the outpatient clinic. When written informed consent is obtained from participants, the participating investigators will introduce information on patients’ clinicopathological characteristics to the CSIS website of the TBCC-ARO trial via a secured module. Furthermore, each patient will receive a code number, and they will be randomized to the RT or low-dose tamoxifen arms after successful registration.