In breast cancer patients, lymph node targeting plays an important role in determining the stage and setting the treatment policy, and the existing methods for this purpose include charcoal staining, needle targeting, and ultrasound-guided skin marking. However, these methods have limitations in terms of detection rate and accuracy, and a new targeting method, LuminoMarkTM, shows the potential to replace them. The purpose of this study is to evaluate the detection rate and safety of lymph node targeting using LuminoMarkTM in breast cancer patients and to verify its effectiveness by comparing it with existing targeting methods. The study was designed as a prospective comparative study, and patients diagnosed with breast cancer and requiring lymph node targeting were divided into the LuminoMarkTM group and the existing method group. The existing method group selects a standard method among charcoal staining, needle targeting, and ultrasound-guided skin marking to perform targeting, and the lymph node detection rate, procedure time, complication rate, and patient satisfaction are the main evaluation indicators in both groups. After targeting, the suitability of the detected lymph nodes is confirmed through pathological analysis, and appropriate statistical analysis is performed to compare the difference in detection rates of each method. Through this study, the investigators evaluate whether LuminoMarkTM provides superior detection rates and safety compared to existing lymph node targeting methods, and based on this, the investigators aim to suggest a more effective and reliable targeting method for breast cancer patients.