INTRODUCTION. There have been only few studies of immunoexpression of p53 in
Wilms tumour (WT), and their results are somewhat contradictory. OBJECTIVE.
The aim of the study was to determine p53 immunohistochemical expression in
WT in relation to its histological components, histological prognostic types
classified according to the SIOP Working Classification of Renal Tumours of
Childhood (2001), and influence of preoperative chemotherapy. METHOD. The
analyses are based on 79 primary WTs treated in single institution according
to SIOP protocols between 1983-2001. For the immunohistochemical detection of
p53, the monoclonal p53 antibody (DO-7, DAKO) was used. Semiquantitative
grading of nuclear staining was done. RESULTS. The immunoexpression of p53
was significantly higher in the blastemal and epithelial than in the stromal
component (p<0.001). It was significantly correlated to WT histological
prognostic types (p=0.039). The exensivity of p53 immunoexpression was higher
in anaplastic components but a difference between WT type of diffuse
anaplasia and all other types was nonsignificant (p=0.10). Five blastemal
type WTs were p53 immunopositive and four immunonegative. There was no
difference in p53 immunopositivity between WT treated with the preoperative
chemotherapy and primary resected WT (p=0.88). CONCLUSION. The
immunoexpression of p53 in WT was significantly higher in the blastemal and
epithelial than in the stromal component. It was in significant correlation
with histological types of WT. The anaplastic component had noticeable but
statistically not significantly higher p53 immunoexpression than
non-anaplastic. The preoperative chemotherapy did not modify p53
immunoexpression of WT which had been found in other similar studies.