This is a randomized, non-inferiority, phase III trial evaluating radiotherapy versus observation after breast-conserving surgery and planned endocrine therapy in patients with stage I luminal A subtype breast cancer defined by the Prosigna (PAM50) test.
Aim of the study
The purpose of this study is to find out whether a genomic test (the examination of specific genes) of breast cancer tissue can be used to select women who can safely avoid radiotherapy because their disease has a low risk of recurrence.
Who can take part?
Patients with a relatively small breast cancer which is considered to have a low risk of recurrence after surgical removal
Procedure
If you participate in the study, you will be randomly assigned to one of two groups.The two treatment groups (study arms) in this randomized study are: Arm A: Standard care radiotherapy and hormone therapy after surgery, OR Arm B: Experimental group - no radiotherapy after surgery (hormone therapy only).You have an equal chance of being assigned to Arm A or Arm B (a 50:50 chance).The hormone treatment is expected to be administered for at least 5 years. You will be followed up for a period of 10 years from randomization.
Compensation
None
Original study name
Randomized phase III trial of adjuvant radiotherapy versus observation after breast-conserving surgery and endocrine therapy in patients with molecularly characterized early luminal A breast cancer
BASEC number
2021-00635
Financial support from
Breast Cancer Trials