Affiliations: Department of Pathology, University Medical Center Utrecht, The Netherlands | Department of Surgery, University Medical Center Utrecht, The Netherlands | Department of Nuclear Medicine, University Medical Center Utrecht, The Netherlands | Department of Pathology, St. Antonius Hospital, Nieuwegein, The Netherlands | Department of Surgery, St. Antonius Hospital, Nieuwegein, The Netherlands
Note: [] Corresponding author: Prof. Paul J. van Diest, MD, PhD, Department of Pathology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA Utrecht, The Netherlands. Tel.: (31) 30 2506565; Fax: (31) 30 2544990; E-mail: p.j.vandiest@umcutrecht.nl
Abstract: Background: The need for routine axillary lymph node dissection (ALND) in patients with invasive breast cancer and low-volume sentinel node (SN) involvement is questionable. Accurate prediction of second echelon lymph node involvement could identify those patients most likely to benefit from ALND. Methods: A consecutive series of 317 patients with invasive breast cancer and a tumor positive axillary SN followed by ALND was reviewed. Clinicopathologic features of the primary tumor and the SN were assessed as possible predictors of second echelon lymph node involvement. Results: Second echelon metastases were found in 116/317 cases (36.6%). Frequency of second echelon lymph node involvement in patients with isolated tumor cells (ITC, N=23), micro- (N=101) and macrometastases (N=193) was 13%, 20% and 48%, respectively (p<0.001). Based on the area % of SN occupied by tumor no subgroup of patients could be selected with less than 20% second echelon lymph node involvement. However, none of the patients with SN ITC or micrometastases and a primary tumor size ≤1 cm (N=12, 3.8%) had second echelon lymph node involvement. Conclusions: Accurately measured SN tumor load predicts second echelon lymph node involvement. However, even in patients with ITC, the second echelon lymph nodes are involved in 13% justifying ALND.
Keywords: Breast cancer, sentinel node, second echelon lymph node metastases, morphometry, tumor load
