OBJECTIVEThe purpose of this study was to investigate the clinicopathologic factors associated with false-negative rate of sentinel lymph node biopsy (SLNB) in breast cancer, and to explore how to reduce the false-negative rate of SLNB.

METHODSThe clinicopathological data of 2265 patients with invasive breast carcinoma who underwent sentinel lymph nodes biopsy (SLNB) in Shandong Cancer Hospital between November 1999 and December 2011 were retrospectively analyzed. We screened 1228 patients who received axillary lymph node dissection after SLNB, and studied the clinicopathological factors that could be associated with false-negative rate of SLNB.

RESULTSThe false negative rate of this group was 10.7% (73/683), accuracy rate was 94.1% (1155/1228), and negative predictive value was 88.2% (545/618). Clinical tumor size (all P < 0.05), calendar year of surgery (all P < 0.05) and numbers of detected SLNs (all P < 0.05) were significantly related with false negative rate and accuracy rate of SLNB, determined by single factor analysis. Logistic regression model analysis showed that calendar year of surgery (P = 0.034) and numbers of detected SLNs (P = 0.012) were independent predictive factors for the false negative rate of SLNB.

CONCLUSIONSFalse negative rate and accuracy rate of SLNB are significantly related to the calendar year of surgery and number of detected SLNs. Strict case selection, standard operation procedure, increaseing numbers of detected SLNs, and improvement of the skill of operators are effective measures to reduce the false negative rate of SLNB.