Although the relationship among different biologic markers of breast c
ancer has been shown to be important in predicting cancer behavior, ex
pression of these markers can be an attribute of the population under
study. Breast cancer is the most common malignancy among Egyptian wome
n. We have studied a number of prognostic tumor markers in infiltratin
g ductal carcinoma in a group of Egyptian women and have correlated ou
r results with traditional histologic parameters of behavior such as t
umor nuclear grade and lymph node status. Seventy-five cases of infilt
rating ductal breast cancer were evaluated from pathology archives. Fo
rmalin-fixed paraffin-embedded sections were immunohistochemically sta
ined for PCNA, p53, c-erbB-2, metallothionein, cathepsin-D, and GST-pi
using specific antibodies and a standard avidin-biotin method. Most h
igh-grade tumors were associated with higher PCNA expression and p53 a
bnormality. There was a significant difference between node-negative a
nd node-positive tumors with regard to their metallothionein content;
other markers, however, did not differ significantly between node-nega
tive and node-positive tumors. PCNA expression, metallothionein expres
sion, and p53 mutation appear to be markers of aggressive tumor behavi
or in Egyptian women with breast cancer.