The Feasibility and Reliability of Sentinel Lymph Node Biopsy After Neoadjuvant Chemotherapy in Breast Cancer Patients With Negative Axillary Lymph Nodes-A Meta-analysis.

Background: The application of sentinel lymph node biopsy (SLNB) has expanded from early breast cancer to locally advanced breast cancer with neoadjuvant chemotherapy (NAC). For patients with negative axillary lymph nodes, performing SLNB before or after NAC remains controversial.

Objectives: To evaluate the diagnostic feasibility and reliability of SLNB after NAC in breast cancer patients with negative axillary nodes at initial diagnosis.

Design: To calculate pooled identification rate (IR) and false negative rate (FNR) of SLNB after NAC on breast cancer patients with initially negative axillary nodes by enrolling relevant studies and perform subgroup analysis by the type of tracer and the number of biopsied sentinel lymph nodes in average.

Data sources and methods: The PubMed, Embase, Cochrane, Web of Science, and Scopus databases from January 1, 2002, to March 1, 2022, were searched for studies. The QUADAS-2 tool and MINORS item were employed to evaluate the quality of the included studies. I² and Q tests were used to evaluate the heterogeneity among the studies. Random-effects model and fixed-effects model were employed to calculate the pooled IR, FNR, and 95% confidence interval (CI). Publication bias was evaluated, and sensitivity analysis was performed. Subgroup analysis was performed according to the type of tracer (single/double) and the number of biopsied sentinel lymph nodes in average (⩽2/>2).

Results: A total of 21 studies covering 1716 patients were enrolled in this study (IR = 93%, 95% CI = 90-96; FNR = 8%, 95% CI = 6-11).

Conclusion: The SLNB after NAC can serve as a feasible and reliable approach in breast cancer patients with negative axillary lymph node. In our study, no significant impact of tracer was found on the IR and FNR of SLNB, and the number of biopsy nodes >2 leads to the decreased FNR of SLNB.