Molecular features of breast cancer predictive of lymph node metastases

The aim of our study was to analyze morphologic and molecular markers of breast cancer relating them to the presence of metastases in axillary lymph nodes. We selected 123 cases of invasive mammary carcinomas stratified into three subgroups: with macrometastases, with micrometastases, and lymph node negative. Presence of metastases was evaluated relating them with morphologic factors (size of primary tumor, type and grade, presence of lymphatic and blood vessel invasion in hematoxylin and eosin-stained slides) and molecular factors of primary tumor (estrogen and progesterone receptors, E-cadherin, Ki67, p53, Her2 expression, and the presence of lymphatic and blood vessel invasion in immunostained sections for D2-40 and CD31). Axillary lymph node metastases were positively related to the presence of lymphatic vessel invasion in hematoxylin and eosin (H&E)-stained slides, when analyzed with or without metastases (p=0.04) and when analyzed in the three subgroups (p=0.002). Lymph node metastases were also positively related to presence of blood vessel invasion identified by immunohistochemistry (IHC) for CD31 (p=0.02). However other morphologic and molecular factors were not related to the presence of axillary node metastases. Lymphatic and blood vessel invasion identified in H&E and IHC-stained slides are positively related to the rmetastatic status of axillary lymph nodes and are predictive of axillary lymph node metastases in breast cancer.