Analysis Of Sentinel Lymph Node Biopsy Of Breast Cancer Patients

Background Sentinel lymph node biopsy (SLNB), which has replaced the standard axillary lymph node dissection(ALND), has become the standard procedure for clinical assessed axillary lymph node-negative breast cancer patients. Quality controlling is needed to ensure the whole team has mastered the technique before its application to replace the ALND. If no metastasis is found in the SLNB procedure, the armpit may be retained; however, in the condition of1-2positive SLNs found during the SLNB, whether the ALND is necessary are still under discussions. With the advantages of the SLNB, the use of it may beyond the existing supporting evidence in some situation.Method Breast cancer patients of Sir Run Run Shaw Hospital from May1999to December2012, who experienced the SLNB procedure, are included in the study. The patients, who were switched to ALND immediately after SLNB, are included to analyze the accuracy and false negative rate (FNR).Two methods of tracers are also compared in terms of accuracy and FNR retrospectively. In all SLNB patients, logistic regression models are used to predict the SLN-positive probability. For SLN-positive patients, the factors that affect the non-SLN status are analyzed; meanwhile, two scoring systems which predict the non-SLN status are tested in the SLN-positive patients. Finally, the effect of neoadjuvant chemotherapy on SLNB accuracies is studied.Result The accuracy rate and FNR are93.1%, and9.5%respectively, with no difference detected in the FNRs and accuracy rates between the two groups of radioactive tracer±blue dye and blue dye tracer alone. Logistic multiple regression model predicts the SLN metastasis with sensitivity and specificity of57.1%and86.4%; in the regression model, the number of the dissected SLN, the pathological types and the treatment types of the primary lesions are related to the SLN significantly. A total of70.0%of the patients has negative SLNs detected; during the average24.1months of follow-up time of these patients, no local relapses and distant metastasis were reported. In total,56.4%of patients who had ALND after a positive SLNB have only the sentinel lymph node metastasis:the primary tumor size and the number of primary tumor lesions proved relate to positive non-sentinel lymph nodes SLNs. Tenon and MD Anderson models have AUC area of Receiver Operating Characteristics (ROC)57.5%and45.3%, respectively. FNR and accuracy of SLNB was16.7%and89.5%, in the patients who have finished the neoadjuvant chemotherapyConclusion The quality of our department of SLNB procedure meets the technical required standards;70%of patients benefit from the SLNB in terms of refraining armpits.56.4%of the SLN-positive patients who continue to ALND are proved only to have sentinel lymph node metastasis. Two models predicting the probability of positive non-SLN metastasis positive are inefficient in the patients of our department. Compared to the pre-chemotherapy SLNB procedures, SLNB after neoadjuvant chemotherapy have a higher FNR and a lower accuracy.