Sentinel Lymph Node Biopsy for Patients
with Breast Cancer

The purpose of axillary node dissection for patients with breast cancer is to obtain information of disease stage, achieve local control, and assist in the decision making for adjuvant therapy. However, for those patients with pathologically negative nodes, dissection does not increase survival. 60% to 70% of patients with early breast cancer have no metastasis to the regional lymphatic basin, so axillary dissection and consequent morbidity can be avoided if there is an accurate alternative for axillary node staging. Sentinel lymph node biopsy (SLNB) may provide physicians with the ability to distinguish negative from positive axillary lymph nodes in a relatively simple fashion.

In this study, radiolabelled sulfur colloid was used as a tracer and left overnight to migrate, after which, SLNB was performed in patients with breast cancer and the feasibility of this approach for Chinese patients was evaluated.

In this study, the success rate using radiotracer and a gamma probe was 95.7%. A 91.4% success rate was experienced in first half of study and all the failures occurred in the first 20 patients. In the second half, the success rate was 100%. A faster and accurate detection and dissection of sentinel node specimen was also experienced in the later patients in this study.

The observed accuracy of SLNs for the detection of metastatic disease in permanent sections was 92.53%, and the false-negative rate was 7.46%. The false-negative rate is of great concern when this procedure is to be applied as a treatment protocol and it was found that the false-negative rate was increased and accuracy diminished with the increase in tumour size. This inaccuracy in larger tumours may be caused by alternative lymphatic drainage pathways or simply by the prevalence of axillary metastasis in patients with larger tumours.

The Fudan University Cancer Hospital breast carcinoma database shows that 23% of all patients with breast cancer in the department had T1 tumours and 56% had T2 tumours. Only 19% of patients with T1 lesions were clinically diag-nosed with axillary lymphadenopathy, and 29% of patients were determined to have a pathologically positive axilla. Currently, all of these patients are being treated with the traditional method of axillary dissection.

The SLNB will establish itself as a safe and effective alternative to axillary dissection in this patient subgroup. This modification will decrease the operative morbidity of surgical therapy for breast cancer, providing accurate staging and more individualised therapy. This minimally invasive axillary staging procedure is a major advance in the surgical treat-ment of breast cancer.