The results of molecular and immunohistochemical testing of HER2/neu status in 2 145 patients with breast cancer are presented. Overexpresion of HER2/neu protein was detected in 591 (27,6%) cases, while 1554 (72,4%) cases were immunohistochemically (IHC) negative.
Discordant phenotype IHC negative/amplification positive was found in 16 patients (1,03%). This group of patients could benefit of Herceptin therapy.