Accurate evaluation of tumor boundaries in breast-conserving surgery is closely associated with reducing the second operation of patients. Meanwhile, accurately assessing sentinel lymph node (SLN) metastasis is crucial for determining the extent of axillary lymph node dissection (ALND) and minimizing complications. Near-infrared-II (NIR-II) fluorescence imaging using molecular agents has shown promise for in situ imaging during resection. However, very effective probes can be applied to clinical trials up to now, which limits the clinical application of fluorescence imaging. Here we developed a new technology that can quickly differentiation between cancer and para-cancer tissue as well as metastatic and normal sentinel lymph nodes(SLN). In brief, the fresh tissues were incubated with the probe immediately after intraoperative resection and imaged to identify the tumor area and distinguish the metastatic status of SLN. The accuracy of fluorescence imaging was confirmed by pathological diagnosis.

After enrollment, the patients received surgical treatment according to clinical diagnosis and treatment.During the operation, the excised breast tissue and SLN was incubated, and the specific procedure was as follows.

1. Preparation of the incubation solution: The probe was dissolved in phosphate buffer saline(PBS) buffer as the incubation solution at room temperature in the dark,with varying concentrations (12.5, 25, 50,100 ug/mL).
2. In vitro incubation of fresh breast cancer or SLN tissues: The fresh excision breast cancer and SLN tissues were completely soaked in the incubation solution for about 1,3, 5, 7 or 10 minutes, followed by 5 minutes rinse with PBST buffer (PBS with Tween 20) and drying with the use of absorbent paper.
3. Analysis of the images in the "Digital Precision Medicine(DPM)" NIR-II system. The DPM parameter was set up before scaling. Then fluorescence imaging was performed with the DPM NIR-II system. And the result was analyzed to identify the tumor area and distinguish the metastatic status of SLN.
4. Confirmed the diagnosis by pathological examination.

Inclusion Criteria:

• Adult patients between 18-75 years of age
• Female
• Patients presenting with a breast nodule or mass presumed to be resectable on pre-operative assessment
• Good operative candidate
• Subject capable of giving informed consent and participating in the process of consent

Exclusion Criteria:

• Patients unable to participate in the consent process
• Patients had contraindications to surgery, such as serious cardiopulmonary disease, coagulation dysfunction, etc
• Other conditions that the researcher considers inappropriate to participate in the study

The investigators plan to enroll 40 female patients, aged 18 to 75 years, who have been assessed to have resectable breast nodules or masses and are scheduled to undergo surgery. During the surgery, the resected tumors and lymph nodes will be incubated with theNIR-II probe(ICG-POL6326) solution, and NIR-II fluorescence signals from the tissues will be collected.