Clinical Research Directory

Patients with an indication for neoadjuvant chemotherapy will be referred for clipping the lesion diagnosed with breast cancer in order to allow subsequent localization of its topography in cases of good response or complete response to treatment. This procedure will be guided by ultrasound, and a specific material consisting of a cannula containing a clip inside is used. Through ultrasound, the cannula is inserted into the center of the target lesion and the clip is positioned at this topography. To allow the clip to be located by ultrasound, it must have a shape that minimizes migration after being positioned, as well as characteristics and dimensions that make it visible on ultrasound, as this method will be preferred for performing the biopsy of the lesion region after neoadjuvant chemotherapy.

Patients with no residual lesion or residual lesion ≤2 cm on MRI and mammography will undergo vacuum-assisted biopsy (VAB) targeting the primary lesion, using the pre-placed clip as a reference under ultrasound or stereotactic guidance. Initially, 6-12 tissue samples will be obtained (7-10G needle) from the clip region, with specimen radiography performed to confirm clip retrieval; additional sampling will continue if the clip is not identified. This initial sample (AM1) will be formalin-fixed. A second set of 6-12 samples will then be collected from the margins of the biopsy cavity ("shaving") and fixed separately (AM2). Following sampling, a new clip will be placed at the biopsy site, and mammographic imaging will confirm its position. The final clip will guide subsequent surgical resection.