Multiparametric flow cytometric analysis of estrogen receptor: a study on egyptian breast cancer patients.

Precise prognostication of breast cancer based on immunohistochemicalfeatures is a challenging assay. Thus, there is a need for more sophisticated prognostic determinants. This work aims to investigate the sensitivity of flow cytometry for the accurate evaluation of steroid receptor positive, tumor cells in formalin-fixed paraffin embedded tissue sections. These sections from forty breast cancer patients were subjected to multiparametric flow cytometric analysis for simultaneous assessment of estrogen receptor and DNA content analysis as well as immunohistochemical staining for steroid receptors. Moreover, tumor markers were estimated in the preoperable sera of these patients. About fifty seven percent of tumors were aneuploid. Seven tumors were interpreted positive for ER by FCM and negative by IHC. Flow cytometric results were confirmed by the traditional prognostic factors. Higher levels of insulin-like growth factor-1 occurred predominantly in aneuploid tumors with lymph nodal metastasis and positively immunostained for both estrogen and progesterone receptors. Multiparametric flow cytometric analysis may allows the detection of specific subset of patients that would otherwise escapes detection.Key words:estrogen receptors; flow cytometry;immunohistochemistry;progesterone receptors; breast tumors; IGF-1 and CA15.3