Axillary lymph node status is the single most powerful prognostic marker for breast cancer. Histopathological assessment of lymph nodes has become the gold standard, although conventional histological work-up may miss 10-20% of node-positive cases, potentially resulting in undertreatment and poorer survival of these patients. Identification and detailed histological assessment of sentinel lymph nodes may improve the error rate of conventional methods. We performed the first 30 lymphatic mappings using patent blue vital staining at our department of Surgery in the second semester of 1997. The success rate of identifying 1 or 2 sentinel nodes was 73.3% (22 cases). Axillary dissection and either breast conserving surgery of mastectomy were performed on all patients. Sentinel lymph nodes were serially sectioned and also investigated by immunohistochemistry using primary antibodies to cytokeratin and epithelial membrane antigen. This correctly predicted the qualitative axillary nodal status gained from all the nodes in 21 cases (95.5%). The only false negative sentinel node was associated with a micrometastatis in a non-sentinel lymph node. From the predictive cases 10 (47.6%) had positive nodes, and half of these had metastases only in the sentinel node. To our knowledge, we are the first in Hungary to report preliminary results from a lymphatic mapping study for breast cancer. It seems evident that assessment of sentinel lymph nodes increases the sensitivity of the less reliable conventional histopathological work-up, and this provides a more accurate staging when performed in conjunction with axillary dissection. On the other hand negativity of the sentinel lymph node may question the need for the clearance procedure.