BRCA1, C-erbB-2, and H-ras gene expressions in young women with breast cancer - An immunohistochemical study

Young age does not seem to be directly related to the aggressiveness of the disease among patients with breast cancer. Identification and analysis of the alterations in a susceptibility gene expression in breast cancer occurr ing in young women may allow identification of those patients in whom tumor s will show an aggressive clinical course. The purpose of the present study was to evaluate the association of BRCA1, H-rns, and c-erbB-2 gene express ion with clinicopathologic parameters of prognosis in breast cancer. Formal in-fixed, paraffin-embedded tissue from 35 patients with breast cancer youn ger than 35 years were immunohistochemically stained for BRCA1, H-ras, and c-erbB-2 expression with monoclonal antibodies. For each antibody, immunore activity was assessed by a semiquantitative scoring system. Each case was a lso graded according to the modified Bloom-Richardson criteria and evaluate d for Ki-67 labeling index, hormonal status, tumor size, distant metastasis , and axillary lymph node involvement. Strong expression of c-erbB-2 and H- ms were observed in 9 cases (25.7%) and 13 cases (37.2%), respectively. Los s of BRCA1 expression was found in five cases (14.3%). Statistical analysis showed that loss of BRCA1 expression was significantly associated with hig her Ki-67 labeling index and greater tumor size. In addition, stronger H-ra s expression was significantly associated with lymph node involvement and d istant metastasis. However, c-erbB-2 immunoreactivity did not show statisti cal significance with any prognostic parameters. We conclude that, although care must be taken not to overstate the importance of our results in view of the lack of information on clinical outcome, alterations in BRCA1 and H- ras gene expression might be of prognostic importance because of the role o f H-ras protein on metastatic behavior and the role of BRCA1 protein on tum or growth. However, c-erbB-2 expression seems to be of no importance in the prognosis of breast cancer occurring in young women.