Background: Widely used in routine for small breast cancers, the sentinel lymph node (SN) biopsy is still discussed in tumors >or= 3 cm.
Methods: From 2000 to 2005, 152 patients with invasive breast tumor pT >or= 3 cm had a SN biopsy systematically followed by complete level I/II axillary dissection. Surgery was always the first stage of the treatment. Detection was done after injection of radioisotope followed by a lymphoscintigraphy and injection of Patent Blue. The SN procedure systematically included palpation of the axilla with removal of any enlarged (>1 cm) and/or abnormally firm node even if neither blue nor radioactive. The sentinel lymph node status was compared with the final axillary status.
Results: Tumor size ranged from 30 to 200 mm (median 42 mm). Lymphoscintigraphy was positive in 98% of the cases. At least one labeled sentinel node was retrieved in 97.4% of the patients. The median number of SN cleared out was 2 (range 1-9). The false negative risk was 4% (4/99). The false negative risk was not related to the tumor size and not related to the number of SN removed.
Conclusions: This study shows that the SN procedure is feasible in patients with breast tumors >or= 3 cm with an acceptable false negative risk <5%, similar to false negatives reported for smaller tumors.