PROLIFERATING CELL NUCLEAR ANTIGEN AND HEAT-SHOCK-PROTEIN-70 IMMUNOLOCALIZATION IN INVASIVE DUCTAL BREAST-CANCER NOT OTHERWISE SPECIFIED

A series of 80 female patients undergoing surgery for primary breast d uctal infiltrating carcinoma not otherwise specified (NOS) was immunoh istochemically studied in order to verify any relationships between Pr oliferating Cell Nulear Antigen (PCNA) immunostaining, Heat Shock Prot ein 70 (HSP70) immunoreactivity, and several clinicopathological predi ctors. Positive PCNA scores (> 20% of strongly immunopositive malignan t nuclei) were observed in neoplastic cells' nuclei in 13 tumors (16.2 5%) and were intimately associated with axillary nodal involvement (p = 0.0131), relatively high tumor grades (p = 0.0016), increased tumor size (p = 0.0312), and low or negative levels of estrogen receptors (p = 0.0323). HSP70 positive immunoexpression in malignant cells' cytopl asm (percentage of HSP70 immunoreactive cells > 10%) was detected in 3 3 samples (41.25%). It correlated significantly with presence of axill ary lymph nodal metastases (p = 0.0033) and rather poor tumor differen tiation (p = 0.0014), whereas an association of borderline statistical significance emerged between HSP70 immunoreactivity and high progeste rone receptor status (p = 0.0637). PCNA positive immunostaining demons trates the tumors' proliferative fraction and might be used as an indi cator of increased malignant potential in breast cancer since it was a ssociated with four adverse prognosticators. HSP70 immunodetection is a probable marker of the biological stress experienced by breast cance r cells, since it was related to relatively high tumor grades. Since b oth proteins may potentially predict disease outcome, their prognostic significance must be validated by direct relation to survival. A mult ivariate statistical analysis including the variables with which both proteins were associated will reveal any possible independent prognost ic value of PCNA and HSP70 immunostaining in local, ductal invasive br east cancer NOS.