HER-3 expression in HER-2-amplified breast carcinoma

Aim of the study: To determine whetherthe expression of HER-3 influences thesurvival of HER-2 positive patients withbreast cancer (BC).Material and methods: In the presentwork, the expression of HER-3 in a groupof 35 HER-2 positive patients with BCwas studied by performing immuno-histochemistry (IHC) in formalin-fixedparaffin embedded tissues.Results: Higher HER-3 status if estimatedby IHC correlated significantly with old -er age of the patients. HER-3 expressiondid not correlate with estrogen or prog-esterone receptor status, pT or pN.There was also no significant differencein disease-free or overall survival (DFSand OS) between groups with differentHER-3 expression, although some ten -dencies were seen as HER-3 expressionin over 50% of cells was a factor of worse5- and 10-year survival.Conclusions: Further studies should beperformed on a larger group of patientsto confirm the prognostic role of HER-3status determined by IHC in BC.Key words: breast cancer, HER-2, HER-3,immunohistochemistry, prognostic fac-tor.