Evaluating TIMP-1, Ki67, and HER2 as markers for non-sentinel node metastases in breast cancer patients with micrometastases to the sentinel node

Tvedskov TF, Bartels A, Jensen M-B, Paaschburg B, Kroman N, Balslev E, Brünner N. Evaluating TIMP-1, Ki67 and HER2 as markers for non-sentinel node metastases in breast cancer patients with micrometastases to the sentinel node. APMIS 2011; 119: 844-52. The aim was to investigate whether the biochemical prognostic markers TIMP-1, Ki67, and HER2 could predict metastatic spread to non-sentinel nodes (NSN) in breast cancer patients with micrometastases to sentinel node (SN). We included all breast cancer patients with micrometastases to SN operated between 2001 and 2007 at the Department of Breast Surgery, Herlev Hospital. The study was designed as a matched case-control study with 25 cases with micrometastases to SN and, in addition, metastatic spread to NSN and 50 matched controls with micrometastases to SN, but without NSN metastases. Patient and tumor characteristics were retrieved from the Danish Breast Cancer Cooperative Group database. Immunohistochemical analyses of TIMP-1 and Ki67 and measurements of HER2 on formalin-fixed paraffin-embedded tumor tissue were performed. No significant differences in the immunoreactivity of TIMP-1 and Ki67 were found between patients with and without NSN metastases. Six of seven HER2 positive patients did not have NSN metastases, but the results did not reach statistical significance. Despite being prognostic markers in breast cancer, TIMP-1 and Ki67 could not predict NSN metastases in women with micrometastatic disease to SN. Larger studies are needed to further validate HER2 as a marker for NSN metastases in these patients.