Is the presence of small volume disease in the sentinel node an indication for axillary clearance?

The finding of micrometastases (M(i)) and isolated tumour cells (ITC) within the axillary lymph nodes of patients with breast cancer has raised the question whether either/both have some prognostic significance. Several studies have shown that compared to node-negative patients, prognosis is significantly poorer in patients with M(i) and ITC. The fact that patients with M(i)/ITC in their sentinel lymph nodes have a systemic relapse risk that is higher than that of node-negative patients may be considered as an indication for systemic treatment. Most studies in the literature suggest that in patients with M(i) or ITC in their sentinel nodes who receive systemic therapy and whole breast radiotherapy, the risk of axillary relapse without axillary lymphadenectomy is under 2%. Given the fact that axillary lymphadenectomy is associated with a 5-25% risk of lymphoedema, we propose that a policy of close follow up should be adopted in these patients rather than axillary lymphadenectomy.