Targeted Axillary Dissection, Sentinel Biopsy, and Tumor Lesion Localization in Breast Cancer Patients Using the New Magnetic "Sentimag" Detection System

The aim of this study is to compare the efficacy of the Sentimag localization system and its tracer Magtrace, superparamagnetic iron oxide nanoparticles, as a tracer in sentinel node biopsy in breast cancer with Tc99 in a single-center prospective study. It also aims to follow skin discoloration after Magtrace injection and describe when and how it resolves. The Magtrace will be injected preoperatively. Sentinel node biopsy will be performed and detection rates will be recorded for both methods.

The other part of the study will be the implantation of the smallest non-radioactive seed, Magseed, in the non-palpable breast cancer lesions. Intraoperative localization of the seed is achieved with the use of the Sentimag probe.

Another part of the study will be the implantation of Magseed in the positive axillary lymph nodes in patients diagnosed with clinically positive lymph nodes that will receive neoadjuvant systemic therapy. To accurately assess the response in the breast and the axilla, it is important that both the positive lymph node/s are marked before neoadjuvant systemic therapy to be able to locate them later on. Systemic therapy can negatively impact lymphatic drainage and hence reduce the accuracy of the sentinel lymph node biopsy (SLNB). However, when SLNB is paired with the removal of the previously positive target lymph node, a technique called Targeted Axillary Dissection, the operation becomes a lot more accurate, with lower morbidity of the patients.

A part of the study is also the verification of the time stability of breast tumor labeling with Magseed in the period from the onset of neoadjuvance to the subsequent operation following the oncological pretreatment of the patient.

All patients will undergo sentinel lymph node detection also by the classic detection system with Tc99.