The Feasibility and Accuracy of Sentinel Lymph Node Biopsy in Initially Clinically Node-Negative Breast Cancer after Neoadjuvant Chemotherapy: A Systematic Review and Meta-Analysis

<div><p>Background</p><p>With the increased use of neoadjuvant chemotherapy (NAC) in breast cancer, the timing of sentinel lymph node biopsy (SLNB) has become increasingly important. In this study, we aimed to evaluate the feasibility and accuracy of SLNB for initially clinically node-negative breast cancer after NAC by conducting a systematic review and meta-analysis.</p><p>Methods</p><p>We searched PubMed, Embase, and the Cochrane Library from January 1, 1993 to November 30, 2015 for studies on initially clinically node-negative breast cancer patients who underwent SLNB after NAC followed by axillary lymph node dissection (ALND).</p><p>Results</p><p>A total of 1,456 patients from 16 studies were included in this review. The pooled identification rate (IR) for SLNB was 96% [95% confidence interval (CI): 95%-97%], and the false negative rate (FNR) was 6% (95% CI: 3%-8%). The pooled sensitivity, negative predictive value (NPV) and accuracy rate (AR) were 94% (95% CI: 92%-97%, I² = 27.5%), 98% (95% CI: 98%-99%, I² = 42.7%) and 99% (95% CI: 99%-100%, I² = 32.6%), respectively. In the subgroup analysis, no significant differences were found in either the IR of an SLNB when different mapping methods were used (P = 0.180) or in the FNR between studies with and without immunohistochemistry (IHC) staining (P = 0.241).</p><p>Conclusion</p><p>Based on current evidence, SLNB is technically feasible and accurate enough for axillary staging in initially clinically node-negative breast cancer patients after NAC.</p></div

Flow diagram of literature search and individual studies identified for this systematic review and meta-analysis.

<p>Flow diagram of literature search and individual studies identified for this systematic review and meta-analysis.</p

The metastatic rate to non-SNs according to SN status in initially clinically node-negative breast cancer patients after NAC.

<p>The metastatic rate to non-SNs according to SN status in initially clinically node-negative breast cancer patients after NAC.</p

Sensitivity, NPV and AR in individual studies.

<p>Sensitivity, NPV and AR in individual studies.</p

Forest plot of the IR.

<p>A fixed-effects model was used to estimate the combined IR, with a result of 96% (95% CI: 95%-97%); I² = 45.6%.</p

Identification rate of SLNB according to mapping method.

<p>Identification rate of SLNB according to mapping method.</p

Forest plot of the FNR.

<p>A fixed-effects model was used to estimate the combined FNR with a result of 6% (95% CI: 3%-8%) I² = 27.5%.</p

Results of quality assessment according to QUADAS 2 for the included studies.

<p>Results of quality assessment according to QUADAS 2 for the included studies.</p

Funnel plot to assess publication bias effect on the FNR.

<p>Each dot represents a separate study. The funnel plot revealed no apparent evidence of publication bias.</p

False negative rate of SLNB according to histological technique.

<p>False negative rate of SLNB according to histological technique.</p