The Multi-center Validation Study of Internal Mammary Lymph Biopsy With Modified Injection Technique in Breast Cancer Patients

In addition to axillary lymph node (ALN), internal mammary lymph node (IMLN) chain is also the first-echelon nodal drainage site for metastasis and it provides important prognostic information in breast cancer patients. However, decision about local treatment of IMLN is still being made based on ALN status. The 2016 National Comprehensive Cancer Network Guidelines recommend internal mammary lymph node irradiation for patients with more than 4 positive ALNs (category 1), and strongly consider irradiation for patients with 1 to 3 positive ALNs (category 2A). Therefore, there will be patients in positive ALN subgroup who just face complications of an unnecessary radiation to IMLN and there will be patients in negative ALN subgroup who do not receive adjuvant radiation therapy they really need. Thus, these inclusion criteria of National Comprehensive Cancer Network might lead to over-treatment and under-treatment. Internal mammary sentinel lymph node biopsy (IM-SLNB) provides a less invasive method of assessing the IMLN than surgical dissection. However, low visualization rate of IM-SLN has been a restriction of IM-SLNB. A modified radiotracer injection technique was established in our previous study. This technique could significantly improve the IM-SLN detection rate. The investigators have validated the accurate of the hypothesis and the modified radiotracer injection technique in the previous study. For axillary sentinel lymph node biopsy, the success rate and the accuracy are the most important technical indicators. The relatively lower false-negative rate is a precondition for the widely application of SLNB. Axillary SLNB needs to be accomplished with the cooperation of multi-disciplinary teamwork, including the breast surgery, the radiologist, the nuclear medicine doctor and the pathologist, in order to obtain a better success rate and a lower false-negative rate. Our previous studies confirmed that the modified radiotracer injection technique can greatly improv