Multicentric Breast Cancer: Sentinel Node Biopsy as a Diagnostic Tool

The sentinel lymph node (SN) is the first lymph node in a lymph node basin to drain a primary tumor. This sentinel node can be removed after labeling with blue dye and/or a radiocolloid by limited surgery. Compared to routine axillary lymph node dissection (ALND), sentinel node biopsy causes less morbidity, lower costs, and is more reliable for axillary staging due to multiple section analysis (Haid et al., 2002). First described by A. Giuliano 12 years ago, sentinel node biopsy (SNB) has become clinical routine, and the standard of care for axillary staging of breast cancer patients in many centers (Giuliano et al., 1994). The 2003 St. Gallen Consensus Panel also accepted it as a diagnostic tool for axillary staging. Many validation studies showed it to be accurate and feasible for unicentric invasive breast cancer (Giuliano et al., 1995; Haid et al., 2003; Veronesi et al., 1999). Accepted indications for SNB, in addition to unicentric breast cancers, are larger ductal carcinomas in situ as well as multifocal cancers up to 3–4 cm in diameter (Lyman et al., 2005). Sentinel Node Biopsy continues to be controversial after preoperative chemotherapy, although the evidence is getting stronger in favour of its usefulness (Haid et al., 2001; Mamounas et al., 2005). Further contraindications are inflammatory breast cancer, palpable axillary lymph nodes, and previous surgery of the breast and axilla.