Patterns of HER2/neu, hormonal receptor expression, and proliferative activity in primary and metastatic breast cancer

1071 Background: The modification of biological features of metastatic sites (MS) in breast cancer patients arise some debatable questions regarding clinically usefull information and safe/efficient methods to detect them. Fine needle aspiration (FNA) of visceral MS is an available tool to characterize tumoral lesion and liquid based citology technique provides usefull cell samples for immunocytochemical and/or molecular assays. Methods: The aim of this study was to compare prognostic and predictive factors obtained from primary tumors (PT) and corresponding MS. Fluorescent in situ hybridization (FISH) was performed for HER2/Neu determination, while ER, PgR, and MIB-1 were detected by immunochemistry using specific monoclonal antibodies on monolayered cell sample and in the corresponding cytoinclusion. FNA with a 21–23 G needle was performed in 20 consecutive breast cancer patients with distant metacronous MS. Results: In 8/20 patients, both ER and PgR were absent in PT and in MS, in 7 were both present, ...