Extent of axillary dissection preceding irradiation for carcinoma of the breast.

"Limited" surgery and irradiation have become more popular therapeutic options for women with stage I and stage II breast cancer, and surgical attention to the axilla is part of this approach. To understand the limitations of whatever axillary procedure is recommended, we undertook a retrospective analysis of the records of 277 women who had undergone radical or modified radical mastectomy. Of this group, 127 had metastases to at least one axillary or interpectoral lymph node. Skip metastases occurred in 13% of women with positive nodes; two women (1.6%) had metastases only to level III nodes, and two women had metastases only to interpectoral nodes. The extremely uncommon occurrence of metastases to level III alone or to interpectoral nodes alone, but the greater likelihood of skip metastases to level II, argues for both level I and level II axillary dissection preceding irradiation for patients with invasive carcinomas of the breast.