Abstract:
Background: Any tumor could be controlled by radiation therapy if sufficient dose was delivered to all tumor
cells. Although technological advances in physical treatment delivery have been developed to allow more
radiation dose conformity, normal tissue is invariably included in any radiation field within the tumor volume and
also as part of the exit and entrance doses relevant for particle therapy. The aim of this study was to evaluate
normal tissue response following radiation therapy by argyrophilic nucleolar organizer region (AgNOR) score in
the normal buccal mucosa form Sudanese patients with head and neck cancer. Methods: The study comprised a total of 80 cytological smears, of whom fifty (50) patients with head and neck cancer that exposed to radiotherapy versus thirty (30) clinically healthy volunteers. The cytological smear was taken from each subject by cytological brush. The smear was then wet fixed in 95% ethyl alcohol and stained with argyrophilic sliver technique to assess the (AgNOR) argyrophilic nucleolar organizer region (AgNOR) score Statistical analysis: All results were analyzed by (SPSS) Statistical Packages for Social Sciences version 16.0 software for statistical analysis. The means were obtained and one sample T-test and other variables frequencies were calculated for comparison and presented in form of figures and tables. Results: the proliferation activity indicated by AgNORs score was highly increase in patients exposed to radiotherapy when compared with clinically healthy volunteers, the mean AgNORs count was found to be statistically significant increase with radiation dose and fraction. Conclusion: AgNOR is an effective tool reflecting the proliferation rate and has a significant prognostic value in the evaluation of radiotherapy effect.