Which of the following statement(s) is/are true concerning the surgical staging of breast cancer?

b. Removal of only level I axillary lymph nodes may understage breast cancer in up to one-fourth of patients

d. A clinically negative axilla will be found to have histologically positive metastasis in approximately one-third of patients

Pathologic staging begins with the initial biopsy. Unless previously secured, fresh tumor needs to be obtained for hormone receptor analysis prior to placement into formalin solution. A period of warm ischemia as short as 30 minutes may cause underestimation of estrogen receptor levels. The need to remove axillary nodes must be determined preoperatively. Axillary lymph node metastasis will be found in approximately one-third of clinically negative axillae, but only if proper axillary dissection is performed. Removal of only level I nodes or “sampling” of axillary lymph nodes in a haphazard fashion increases the risk of injury to major axillary neurovascular structures and may understage up to 25% of women. Proper staging of axillary lymph nodes should include en bloc removal and examination of level I and level II nodes. When conducted for staging, axillary lymph node dissection should not include removal of level III axillary nodes; in fewer than 2% are metastases present in level III nodes when level I and level II nodes are negative. Removal of level III nodes, however, does increase the incidence of postoperative arm lymph edema almost fivefold. Therapeutic axillary lymph node dissection performed for palpable disease in the axilla should include removal of all levels to clear gross disease.