Axillary lymph node dissection in patients with breast cancer and sentinel lymph node micrometastasis or isolated tumor cells: is it necessary?

AIMS AND BACKGROUND Sentinel lymph node biopsy is the standard method for axillary lymph node staging in patients with early stage breast cancer. The aim of the study was to evaluate the necessity of axillary lymph node dissection in patients with breast cancer and sentinel lymph node micrometastasis or isolated tumor cells. METHODS Sentinel lymph node biopsy was performed in 136 patients for breast cancer staging: 16 of them (11.7%) were found to have micrometastasis or isolated tumor cells and underwent axillary lymph node dissection. Micrometastases were considered when tumor invasion was ≤ 2 mm and >0.2 mm in diameter and isolated tumor cells when detected alone or in clusters of <0.2 mm in diameter. The dissection of the three axillary lymph node levels of Berg was performed in all cases. RESULTS Two patients (12.5%) presented isolated tumor cells and 14 (87.5%) micrometastasis in the sentinel lymph node. Among them, 25% presented nonsentinel axillary lymph node tumor invasion, whereas 75% had no further nodal involvement. CONCLUSIONS Results suggest that micrometastasis or isolated tumor cells of the sentinel lymph node represent the only site of cancer involvement of the axilla, especially in patients with early breast tumors, and that axillary lymph node dissection may be unnecessary in these cases and represent an overtreatment.