EXPRESSION OF HER-2/NEU ONCOGENE IN BREAST-CANCER - CORRELATION OF QUANTITATIVE IMMUNOCYTOCHEMISTRY AND PROGNOSTIC FACTORS

HER-2/neu oncogene expression by breast carcinomas (n = 208) was investigated on frozen sections using monoclonal anti-p185 HER-2/neu protein. Results were evaluated by computer-assisted image analysis and correlated with morphological prognostic factors, hormone receptor antigenic sites, Ki 67 antigen and cathepsin content, nuclear morphometry, DNA content and Ag NORs, which were also evaluated by image analysis. All tumors were anti-p185 HER-2/neu immunoreactive, but in 40% of the cases, less than 20% of the tumor cell surface was immunostained. In terms of both extent and intensity, immunostaining which was greatest in comedocarcinomas correlated with tumor size (p = 0.019) and Ki 67 (p = 0.0012) and cathepsin (p<0.0001) content. No correllation was found with tumor grade, axillary lymph node involvement, hormone receptor sites, nuclear DNA content and Ag NORs distribution and morphometry.