Indications for sentinel lymph node biopsy in multifocal and multicentric breast cancer

Background: Multifocal and multicentric breast cancers have been regarded as relative contraindications for sentinel lymph node (SLN) biopsy, because initial validation studies noted an association with greater false-negative rates. The purpose of this study is to perform a meta-analysis of the literature evaluating the feasibility and accuracy of SLN biopsy in multifocal and multicentric breast cancer. Methods: A PubMed search retrieved original articles published between 2000 and 2010 in which the authors evaluated the accuracy of SLN biopsy in multifocal and multicentric breast cancer. Sixteen original articles were included in our meta-analysis. Results: Nine-hundred thirty-two patients with multifocal and multicentric breast cancer underwent SLN biopsy followed by axillary lymph node dissection. The overall accuracy rate and false-negative rate are 96% and 7.7%, respectively. Of the 37 false-negative biopsies, 7 patients had an additional relative contraindication for SLN biopsy. If we exclude these patients with additional known relative contraindication to SLN biopsy, the accuracy and false-negative rates are 96.7% and 6.3%, respectively. Conclusion: When a multifocal or multicentric breast cancer has an additional relative contraindication to performing SLN biopsy, such as neoadjuvant chemotherapy or T > 5 cm, the false-negative rate increases.