T-REX is a randomized multicenter, non-inferiority trial.
Aim: To evaluate whether regional radiotherapy may safely be omitted in clinically node negative breast cancer patients with one or two sentinel node macrometastases and an estrogen receptor positive, HER2-negative tumor. Leading to an improved quality of life and reduced side effects, without worsening recurrence free survival at five years.
Intervention: Patients will be randomized to locoregional radiotherapy towards the breast/chestwall and regional lymph nodes vs. to a de-escalated radiotherapy.
In the intervention arm no lymph node irradiation will be given. Radiotherapy is still given to the remaining breast after breast conserving surgery, but no radiotherapy is given after mastectomy.
Sample size: 1350 patients
Primary end-point: Recurrence free survival at five years.
Gene expression analysis: For all patients gene expression analysis for the gene signatures ARTIC, POLAR and OncotypeDX will be performed and related to risk of recurrence and benefit of adjuvant radiotherapy.
Primary unifocal or multifocal invasive breast cancer T1-T2.
Clinically N0.
Macrometastasis (>2mm) in 1-2 lymph nodes at sentinel node biopsy.
Oral and written consent.
Regional or distant metastases outside the ipsilateral axilla.
Previous RT towards the planned target area, i.e. the ipsilateral chest/lymph nodes.
Neoadjuvant systemic therapy.
Axillary lymph node dissection or other previous axillary surgery on the affected side.
Region Skane
Lead sponsor
Exact Sciences Corporation
Collaborator