The authors report their experience gathered from December 1998 to December 1999 in the use of the sentinel lymph node (SN) method in breast cancer treatment. In 20 out of 21 cases (95%) localization of the SN was obtained by scintigraphy while in 19 cases (90.5%) the SN was found during surgery. Histological examination of the axillary lymph nodes gave a 95% accuracy with only one negative SN associated with positive axillary lymph nodes out of a total of 19. However, the authors have subjected all patients to a complete three-level axillary dissection since they believe the method applied has not yet been fully validated.