Metastases to the upper levels of the axillary nodes in carcinoma of the breast and its implications for nodal sampling procedures.

An axillary lymphadenectomy is important for the staging and treatment of metastatic disease in patients with carcinoma of the breast, especially since the nodal status is a primary criterion for using systemic adjuvant chemotherapy. As more conservative operations combined with radiation therapy have been increasingly used for selected patients with carcinoma of the breast, an axillary node sampling instead of a complete axillary dissection has been advocated by some oncologists. However, the possibility exists that node "sampling" understages patients who would otherwise have received adjuvant chemotherapy to improve their chances for cure. We retrospectively examined this hypothesis in a group of 72 patients with documented nodal metastases who had a radical mastectomy (modified or Halsted). Overall, 18 of 72 patients (25 per cent) had metastatic involvement confined to the upper axillary nodes (Levels II and III). Of the patients with no clinically palpable nodes, 32 per cent had metastatic nodal involvement confined to the upper nodes. Medial quadrant lesions exhibited this tendency more than lateral quadrant lesions (50 versus 20 per cent). Larger primary tumors were associated with an increasing likelihood of involved nodes; however, even 14 per cent of the smallest primary lesions of the breast (less than 2 centimeters) had metastases exclusively to the upper axillary region. Since approximately 40 per cent of the patients with carcinoma of the breast have nodal metastases and since 25 per cent of these metastases are confined to the upper portion of the axilla, it is estimated that at least 10 per cent of all women with carcinoma of the breast (25 X 40 per cent) would be understaged by an axillary node sampling procedure.