Prognostic value of HER-2/NEU expression in breast carcinoma

ABSTRACT

Although axillary lymph node status is still the most powerful prognostic indicator, 15 to 45% of patients whose lymph nodes do not contain metastases still experience a recurrence and die. Conversely, up to 15% of patients with >10 positive lymph nodes treated only with surgery and radiotherapy survive without recurrence or metastases. Because of this, other prognostic markers have been developed to improve prognostic accuracy, particularly in the group of patients with node-negative tumors. To study the expression and prognostic value of HER-2/neu in breast cancer patients, to determine its role in defining high risk patients in cases with a relatively good prognosis [e.g. node negative cases and progesterone receptor [PR] positive cases]. This study included 90 patients with invasive breast cancer [44 patients node positive and 46 patients node negative]. Study for histopathologic prognostic factors was done and immunohistochemical study for HER-2/neu, oestrogen receptors [ER] and pogestrone receptors. HER-2/neu was positive in 26.1% of lymph node negative cases, positive in 31.8% of lymph node positive cases and positive in 28.9% of all patients.HER-2/neu overexpression, by itself, possessed a highly significant prognostic value for shorter overall survival [O.S] and disease free survival [D.F.S] for the whole patients group and for progesterone receptor positive cases. However, in the lymph node negative group it has significant prognostic value for shorter overall survival, by itself, but it lost its effect on steroid receptors. HER-2/neu overexpression seemed to identify patients with poor outcome from those subgroups known to have good prognosis e.g. progesterone receptor positive cases [regarding both disease free survival and overall survival] and node-negative patients [regarding overall survival]