Diagnostic HER2DX-guided Treatment for Patients wIth Early-stage HER2-positive Breast Cancer

This is an international, multicenter, prospective, randomized, two-arm, open-label, phase III study to evaluate the HRQoL, safety, efficacy, and economical costs of using HER2DX in patients with stage II to IIIA HER2-positive breast cancer, suitable for neoadjuvant therapy. A dual primary endpoint with an according multiple testing procedure is defined in this study. First, the study will evaluate superiority in quality of life using i) the GHS scale from the EORTC QLQ-C30 questionnaire version 3.0 and ii) the score from the FACIT Fatigue Scale.