The significance of one positive axillary node

Aims The aim of this study was to identify a subgroup of patients with breast cancer that can safely avoid axillary dissection. Methods Using data collected by the Eindhoven Cancer Registry, we compared the clinico-pathological features of 489 patients with only one positive lymph node to those of 817 patients with more than one positive lymph node in the axilla. All patients underwent complete axillary dissection, not preceded by a sentinel node biopsy. Results Tumour size greater than 1 cm, harvesting more than 15 axillary lymph nodes at histopathological examination, metastasis size larger than 2 mm, extranodal extension, and nodal involvement of the axillary apex are independently associated with the occurrence of more than one metastatic axillary lymph node. Conclusion No subgroup could be identified in which axillary dissection can always be omitted. However, tumour size<1 cm, finding a micrometastasis rather than a macrometastasis, and especially not finding extranodal extension were independently associated with finding only one positive axillary lymph node.