[Molecular markers in breast cancer: practical aspects and morphologic evaluation].

The evaluation of molecular markers in breast carcinomas can be routinely assessed by (i) histochemistry for ploidy measurement (Feulgen stain) and for AgNORs counts, and by (ii) immunocytochemistry (Ki67, cathepsin D, pHER-2/neu, EGFR, ER, PR, pS2, p53). Immunocytochemical assays are correlated to biochemical assays and are particularly relevant in small tumors in which only small amount of tissue is available. Immunocytochemical assays provide for data additional to current histological methods, useful for prognostic evaluation and for the selection of node negative patients who may benefit from adjuvant therapy. Nevertheless, immunocytochemical assays can be used for clinical purposes only if they are standardized (frozen sections, image analysis).