[Expression of epidermal growth factor receptor and p53 protein in superficial cancer of the urinary bladder]

To determine the relationship of the immunohistochemical expression of p53 and EGF-r (epidermal growth factor receptor) and the recurrence rate and disease-free interval in superficial bladder cancer.

144 patients with superficial transitional cell carcinoma of the bladder were studied over a period of three years. Direct dilution anti-EGF-r monoclonal antibody (Biogenex, San Ramon, CA 94583, USA) was utilized for EGF-r determination. Anti-p53 mouse monoclonal antibody (DO7, Novocastra, Newcastle, 24 Claremont Place, UK) at a concentration of 1:100 was utilized for protein p53 determination and was considered negative if less than 10% of the tumor cells were stained and positive if 10% to 100% of the cells stained. EGF-r was determined only as either positive or negative regardless of percent of expression.

55 patients (38%) showed EGF-r and 14 (9.7%) showed p53 expression. The disease free survival was 54.08 months in the patients that showed EGF-r expression vs 30 months for those that did not, the difference being statistically significant (p = 0.027). However, no differences were found in this regard for p53 expression. Tumors that expressed EGF-r recurred in the same site as that of the primary tumor. By contrast, those that did not express EGF-r recurred in another or in multiple sites.

The risk of recurrence is lower in bladder tumors that express EGF-r than those that do not, and when they recur, this generally occurs in the same site as the primary tumor. However, determination of p53 expression was not useful in determining the risk of recurrence or progression of superficial bladder tumors.