Prognosis of Head and Neck Tumours in Relationto Tumour Suppressor p53

Overview

Up to now there is no reliable tool for prediction of tumor biological behavior andtherapeutic response to indicated therapy. Percentage of p53 mutations in H&NSCC is reasonablyincreased. Nevertheless, the prognostic value of common p53 mutation in H&NSCC has not beenevaluated so far. Study objective: to find a correlation of tumor suppressor p53 mutation incidencein H&NSCC determined by immunohistological assay and FASAY (functional analysis of separatedalleles in yeast) fucntional test with grading, staging, tumour localization and overall survival rate.Materials and methods: specimen of 50 patients with H&NSCC mostly resected during oncosurgeryor obtained fromprobatory excision were included in the study. Gene p53was functionally analyzedby FASAY and mutation incidence by immunostaining with D07 Dakocymation monoclonal antibody.Results: Gene p53 mutation incidence determined by FASAY, respectively immunohistochemicaly,is 62%, respectively 64%. A statistical evaluation revealed a significant correlation betweenresults of both methods (p=0.0024). Even though FASAY showed closer correlation with clinicalparameters, easily available immunostaining could be used in clinical praxis and FASAY fits betterfor research purposes. Gene p53mutation incidence didn’t correlate with proliferative parameters,i.e. grading, Ki-67 or T-category of TNM classification at all. However, gene p53 showed limitingcorrelation (p=0.06) with metastatic potential. We concluded that the higher incidence of p53mutations the higher frequency of metastases. Patients with high incidence of p53 mutationsempirically had shorter survival rate, but statistical results revealed no significant correlation.Conclusion: In accordance with other studies, we concluded that p53 prognostic value should beconsidered limiting. However, we pressume further research on biomarkers like gene p53 verypromising.

Key words:
tumour supressor p53 mutation, H-NSCC, prognosis.