The prognostic value of MDM2 overexpression in superficial urothelial bladder carcinoma

The prognostic significance of p53 accumulation and MDM2 overexpression in superficial and papillary urothelial cell carcinoma (UCC) of the bladder has not yet been established. Therefore, MDM2 and p53 protein were investigated focusing on tumour grade and muscularis mucosae invasion in order to identify their prognostic significance. Thirty-five archival UCC were studied by immunohistochemistry using monoclonal antibodies DO7 against p53, and IB10 against MDM2. MDM2 overexpression was observed in 51.4% of the cases. The recurrence rate for patients with MDM2 overexpression was 7.09 fold higher than for those without MDM2 overexpression. p53 accumulation was not related to prognosis. There was no significant difference between low and high grade tumours in regard to MDM2 overexpression and p53 accumulation. pTa cases presented the higher frequency of MDM2 positive cases (66.7%) and a lower frequency of p53 accumulation (33.3%). MDM2 overexpression does not seem to be related to muscular mucosae invasion. Thus, MDM2 status may well be a prognostic marker in superficial urothelial bladder carcinomas.