Sentinel lymph node biopsy (SLNB) is an accurate alternative to complete axillary lymph node dissection (ALND) in clinically node-negative breast cancer patients. A previous breast biopsy has been considered a relative contraindication to SLNB. We examined the accuracy of SLNB by following the axillary relapses after the procedure in patients who had undergone a breast biopsy before SLNB.

Up to December 2003, 4351 patients with the diagnosis of invasive breast cancer underwent SLNB at the European Institute of Oncology. Already, 543 of these patients had undergone a breast biopsy; from June 1997 to January 2004, these patients received SLNB by lymphoscintigraphy performed on the biopsy area. We followed these patients with a clinical assessment every 6 months and instrumental examinations every year, particularly focusing on the research of axillary relapse of disease.

In 70.4% of cases, the sentinel node was negative, and only three cases underwent further axillary dissection. The sentinel node was identified in 99% of cases and this was the only positive node in 61.5% of cases with positive axillary nodes. The median follow-up was 2 years; 4 nodal recurrences were observed: 3 axillary lymph node relapses and 1 loco-regional.

SLNB accuracy after a previous breast biopsy is comparable with the results obtained in validation studies. SLNB after a previous breast biopsy can be considered a standard procedure. Lymphoscintigraphy identifies the sentinel node in 99% of patients.