COMPARATIVE EXPRESSION OF P53 IN LOW-GRADE AND HIGH-GRADE UROTHELIAL CARCINOMA OF THE URINARY BLADDER: A CROSS-SECTIONAL STUDY

Abstract

Background: Urothelial carcinoma (UCa) of the urinary bladder is a biologically heterogeneous disease, and histological grade does not necessarily reflect the behavior of the tumor. The tumor suppressor p53 has been identified as a potential biomarker linked to tumor growth and aggressiveness. Objective: To compare the immunohistochemical expression of p53 in low-grade and high-grade urothelial carcinoma of the urinary bladder and its correlation with clinicopathological features. Methods: This analytical cross-sectional study conducted at Pak International Medical College analyzed 100 patients with histopathologically confirmed UCa including 50 low-grade and 50 high-grade. Immunohistochemical staining was performed on formalin fixed paraffin embedded tissue sections for p53. The relationships between p53 expression and clinicopathological variables were determined by Chi-square and logistic regression analysis, and a p<0.05 was considered statistically significant. Results: High-grade UCa showed higher expression of p53 (86.0%) than low-grade UCa (48.0%) (p<0.001). Smoking history, tumor size, more than one tumor, muscle invasion, lymphovascular invasion, perineural invasion, and pathological stage were significantly associated with positive p53 expression. In multivariable logistic regression, p53 positivity was an independent factor of high-grade UCa (adjusted OR 5.83, 95% CI 2.01–16.89, p=0.001). Conclusions: The high expression of p53 is closely associated with the histological grade and the aggressive pathological characteristics of UCa. Immunohistochemical analysis of p53 could be a valuable biomarker for prognostic evaluation and risk stratification in the common pathological practice.