Evaluation of P53 and CK20 Immunohistochemical Markers in Comparison with Morphologic Findings in Low- and High-grade Urothelial Carcinomas.

Background & Objective: Urothelial carcinoma is the seventh most common cancer in the world. The histological classification of papillary carcinoma is one of the most important determinants for its prognosis. Sometimes there is an overlap in the extent of the tumor, and the accurate microscopic diagnosis of the tumor is not always easy. The aim of this study was to evaluate P53 and CK20 immunohistochemical markers in comparison with morphologic findings in low- and high-grade urothelial carcinomas.

Methods: For this descriptive study, urinary bladder samples were collected from 50 cancer patients who had undergone biopsy and surgery in Shohaday-e Tajrish Hospital of Tehran, Iran, during the years 2015-2016. P53 and CK20 were studied, and the demographic and histopathological characteristics of the tumor were also analysed.

Results: The mean age of patients enrolled in this study (48 males and 2 females) was 65.8±11.9. Twenty-five cases presented with low-grade and 25 cases presented with high-grade papillary urothelial carcinomas. Sensitivity, specificity, and positive and negative predictive values for P53 were 48%, 80%, 70.5%, and 60.6%, respectively, while the same values for CK20 were 44%, 92%, 84.6%, and 62.2%, respectively. Immunohistochemical results were also positively correlated with the extent of the tumor.

Conclusion: Based on the results, P53 and CK20 may serve as specific markers for diagnosis of low- and high-grade papillary urothelial carcinoma but not sensitive. P53 and ck20 staining have also a high specificity as 80% and 92% and low sensitivity compared to the low and high morphology of papillary carcinoma, thus their positive and their staining intensity are valuable for diagnosis, but their negative results are not determinant.