Purpose: We examined the presence of the p53 and Bcl-2 oncoproteins, as detected by immunohistochemistry, in muscle-invasive bladder cancer and correlated this with survival.
Materials and methods: Formalin-fixed cystectomy specimens from 41 consecutive patients with mean follow-up of 52 months were used. Five patients were either lost to follow-up or died of other diseases and were not included in the survival evaluation.
Results: Eighteen of 36 patients died of metastatic transitional cell carcinoma. p53 immunostaining was found in 61% of patients. In 21 of 23 this staining was homogeneous, with more than 75% of cancer cells staining using a DO-1/DO-7 antibody cocktail. p53 staining was not correlated with stage (p>0.25) or grade (p<0.10) in these invasive cancer specimens. Contrary to recent studies p53 immunostaining was not correlated with disease-specific survival. Bcl-2 immunostaining was found in 28% of patients and was not correlated with grade (p>0.25) or disease-specific survival. No combination of p53 and Bcl-2 staining gave added predictive information.
Conclusions: Cytoplasmic Bcl-2 is found in a small percentage of these cancers and does not correlate with prognosis. Further, p53 molecular overexpression is detected in the majority of muscle-invasive bladder tumors as a field defect. However, in patients undergoing cystectomy, it does not correlate with prognosis.