Study to Assess the Success of Preoperative Chemotherapy for Breast Cancer Using Vacuum-Assisted Biopsy

Breast cancer is one of the most common cancers among women. The different types of breast cancer differ in their tumor biology based on the presence of certain genes or proteins. In certain cases, particularly with more aggressive tumor types such as HER2-positive or triple-negative (hormone receptor-negative and HER2-negative) breast cancer, chemotherapy is administered before surgery; this is referred to as neoadjuvant chemotherapy (NAC). The goal is to shrink or completely eliminate the tumor to make breast-conserving surgery possible. Studies show that in more than half of these patients, NAC results in complete tumor regression (pathological complete remission = pCR). The imaging techniques used, such as magnetic resonance imaging (MRI) or ultrasound, are often not precise enough to reliably determine whether residual tumor disease is still present. For safety reasons, surgery is therefore still performed even when the tumor appears to have completely regressed, either to confirm a complete response or to completely remove any residual disease.

The goal of the VISION I study is to investigate whether a vacuum-assisted biopsy—that is, a targeted tissue sample taken with a hollow needle at the site of the former tumor shortly before surgery—can help better assess the situation. The biopsy is performed under ultrasound or X-ray guidance. The tissue sample is then compared with the tissue obtained during surgery. The goal is to evaluate the reliability of this method and thereby avoid unnecessary surgeries in the future. The study is not testing a new treatment but is investigating an additional method for assessing treatment success. It is a single-arm, open-label study, which means that all patients receive the same treatment and diagnostic procedures.

Eligible participants are women and men aged 18 and older with a single, invasive breast tumor (1–5 cm in size) of the luminal B, HER2-positive, or triple-negative type that was marked prior to chemotherapy. An MRI (or, alternatively, an ultrasound) must show complete or near-complete regression of the tumor following neoadjuvant chemotherapy. The former tumor site must be accessible for a biopsy. Patients who have previously undergone breast surgery or radiation therapy on the same breast are excluded.