Aims-To study the possible accumulation of p53
protein in
inverted papilloma of the urinary bladder.Methods-
Formalin fixed,
paraffin wax embedded sections from 14 cases of
inverted papilloma of the urinary bladder were studied retrospectively. Accumulation of p53 was detected by immunohistochemistry using a mouse
monoclonal antibody directed against p53. p53
protein reactivity was scored as follows: 0 = 10%; 1 = 10% to <30%; 2 = 30% to <50%; and 3 = >50% of cells p53 positive.Results-The 14 sections were scored as follows: 3 in four cases; 2 in four cases; 1 in one case; and 0 in five cases. Overall, nine (64%) of the 14 cases were positive for p53
protein.Conclusions-The accumulation of p53
protein in
inverted papilloma of the urinary bladder suggests that p53 may have has an important role in the neoplastic process of this tumour. However, the benign nature of
inverted papillomas suggests that p53
protein accumulation is not related to tumour invasiveness and
metastasis. p53 reactivity cannot be used as a marker of
malignancy for urothelial
neoplasia. Further studies are required to determine the role of p53
protein in the
oncogenesis of urothelial
neoplasms.