The Impact of the Recurrence Score on Treatment Decisions Following Surgical Removal of Early-Stage Breast Cancer

Breast cancer (mammary carcinoma) is a malignant disease of the mammary gland tissue characterized by the uncontrolled proliferation of mammary gland cells. In early-stage hormone receptor-positive breast cancer, when the tumor is locally confined and has not yet spread to other organs, the question often arises after surgery as to whether chemotherapy is necessary in addition to anti-hormone therapy. The goal is to prevent a relapse—that is, the recurrence of the tumor in other parts of the body. This decision depends on various factors, such as tumor size, cell division rate, and lymph node involvement. The selection of the optimal treatment could be aided by considering the so-called Recurrence Score (RS). The RS is a test result determined through genetic analysis of the tumor (Oncotype DX test). This test assesses the risk of recurrence based on 21 genes in the tumor tissue and classifies patients into three risk groups: low, moderate, or high.

The goal of the IRMA study is to investigate the influence of the Recurrence Score on treatment decisions following surgery. The aim is to avoid unnecessary chemotherapy in low-risk patients while ensuring that high-risk patients receive the necessary additional treatment.

The IRMA study is non-interventional, meaning it observes how the RS influences treatment decisions in everyday clinical practice without testing a new drug. In addition, the study will investigate whether there is a correlation between the RS and the spread of tumor cells in the bone marrow. The study is open-label, meaning that both medical staff and patients know whether adjuvant chemotherapy is being administered. Patients will be monitored for up to 1 year as part of the study.

Eligible participants are adult women with unilateral, non-metastatic, hormone receptor-positive, and HER2-negative breast cancer with no more than three affected lymph nodes. No prior systemic (drug-based) therapy may have been administered, and participants must not have a previous cancer diagnosis (within the last 10 years) or be pregnant. The tumor must be operable, and treatment must take place at the University Hospital of Tübingen.