We investigated the feasibility and clinical applicability of sentinel lymph node biopsy (SLNB) in patients with neoadjuvant chemotherapy, tumor size >2 cm, and privious excisional biopsy.

175 patients with 176 breast cancer underwent aLNB between October 2001 and October 2002. Among them twenty-five patients with locally advanced breast cancer underwent SLNB after neoadjuvant chemotherapy. Eightynine (50.6%) had primary tumor >2 cm. The recent biopsy method used before SLNB was excision in thirty-one (17.6%) procedures. The identification rate, false-negative rate, negative prediction value and accuracy of SLNB were determined.

SLNB was successful in 164 of 176 cases (detection rate, 93.2%). The identification rate of patients who had neoadjuvant chemotherapy was 68% and lower than that of who had not (97.3%), significantly (P=0.00). However, mapping success was not influenced by large tumor size (>2 cm) or previous excisional biopsy. The false-negative rate and accuracy were 16.5% and 91.5, respectively. The false negative rate was 21.3% (3/14) in those patients received neoadjuvant chemotherapy compared with a 15.5% in those patents not received neoadjuvant chemotherapy (P>0.05). In addition, Tumor size >2 cm and previous excision did not adversely impact the false negative rate and accuracy.

Neoadjuvant chemotherapy was associated with a lower identification rate for SLNB. But if detected, SLNB after neoadjuvant chemotherapy might reliably predict axillary status. SLNB is feasible and accurate in patients with large tumor (>2 cm) and previous excision.