1. ¹Department of Pathology, University of Kentucky, Lexington, KY, USA
2. ²Veterans Administration Medical Center, Lexington, KY, USA

Correspondence: Dr H Rutledge, MD, Department of Pathology, University of Kentucky, Suite MS 117, 800 Rose Street, Lexington, KY 40536-0001, USA. E-mail: hlr1998@aol.com

Received 8 October 2004; Revised 7 January 2005; Accepted 8 January 2005; Published online 11 March 2005.

Abstract

The decision whether to proceed with complete axillary node dissection based on sentinel node status is clear for patients with negative or macrometastatic disease. However, the course of action based on sentinel node micrometastasis remains controversial. We reviewed 358 cases from 6/1999 to 7/2003. All sentinel nodes were evaluated at three levels by frozen section, touch preparation, and scrape preparation. Micrometastasis was defined as tumor deposits between 0.2 and 2 mm. Size, grade, and lymphvascular invasion of the primary tumor, as well as number, status, size of metastatic disease, and presence of extranodal capsular extension of sentinel and nonsentinel nodes were recorded. Of the 358 cases, 89 had positive sentinel nodes, 29 of which represented micrometastases. Only one (3%) of the 29 cases contained a nonsentinel node with macrometastasis. In 60 of the 89 cases sentinel nodes contained macrometastases. Of these, 38 cases (63%) had metastatic tumor in nonsentinel nodes. Intraoperative consult was performed in 53 of the 89 cases with positive sentinel nodes. Only 1 of the 19 (5%) intraoperative consult cases with micrometastatic sentinel nodes had positive nonsentinel nodes, while 21 of 34 (62%) of macrometastatic sentinel nodes at intraoperative consult had tumor in nonsentinel nodes. No single variable studied discriminated between micro- vs macrometastatic disease. At intraoperative consult, macrometastatic disease was present in all three diagnostic preparations, while diagnostic material in micrometastatic sentinel nodes was usually present in only one modality. This analysis suggests that the risk of finding tumor in nonsentinel nodes differs significantly between cases with micro (3%)- vs macro (63%)-metastatic disease in sentinel nodes. This holds true for cases assessed by intraoperative consult. Considering the known morbidity of complete axillary dissection, assessments of risk vs benefit of undertaking this procedure should be performed on a case-by-case basis in patients with sentinel node micrometastases.