p53 anderbB-2 protein overexpression are associated with early invasion and metastasis in bladder cancer

Overexpression of p53 anderbB-2 was studied by immunohistochemistry in formalin-fixed tissue samples of 179 patients with transitional cell carcinoma of the urinary bladder. p53 immunostaining was strongly correlated with tumour stage (P<0.0001). This was driven by a marked difference in p53 expression between pTa (37% positive) and pT1 (71%) tumours, while there was no difference between pT1 and pT2-4 tumours. Similarly, a strong overall association between p53 expression and grade (P<0.0001) was driven by a marked difference between grade 1 (28%) and grade 2 tumours (71%), and there was no significant difference between grade 2 and grade 3 tumours. Surprisingly, the frequency oferbB-2 overexpression was higher in pT1 tumours (74%) than in either pTa (49%;P=0.0265) or pT2-T4 (56%;P=0.0645) tumours. Both p53 anderbB-2 expression was also associated with metastasis. Metastases were found in 77% of patients with p53 positive primary tumours, but in only 50% of the patients with p53 negative primary tumours (P=0.022). Metastases were found in 66% of patients witherbB-2 positive primaries, but in only 37% of theerbB-2 negative primaries (P=0.020). Of 32 patients with positivity for both p53 anderbB-2, 84% developed metastases, as compared to 49% of patients with positivity for either one or neither positive (P=0.002). We conclude that both p53 anderbB-2 over-expression are associated with early invasion in bladder cancer. Furthermore, p53 anderbB-2 may be important predictors for metastasis.