G. Sathish Kumar, Haris C. H2

BACKGROUND Urothelial Cell Carcinoma (UCC) of urinary bladder is the seventh commonest cancer wordwide.1 At initial diagnosis, 30% of UCC display solid and invasive growth patterns and are locally advanced or metastatic at the time of diagnosis. 70% of tumours are noninvasive papillary UCC confined to the epithelium and subepithelial connective tissue,2 which can be managed by endoscopic resection. A significant number of post-resected cases, progress for recurrence of tumour and infiltration to muscle layers. Invasive bladder cancer has high morbidity and uniform mortality when it is metastatic. There are no effective tools to predict aggressiveness of tumour, so that these cases can be managed more successfully. Mutated Tp53/p53 is the genetic abnormality most frequently associated with UCC and related to cell transformation, malignancy and high recurrence rates.2 MATERIALS AND METHODS This is a descriptive study conducted in the departments of urology and pathology and during the period of March 2014 to February 2015. All consecutive cystoscopic biopsies, Trans urethral resection of bladder tumour (TURBT) and radical cystectomy specimens histopathologically diagnosed as UCC were included in the study. p53 expression was assessed by immunohistochemistry. Positive and negative controls were used. Bivariate analysis was done using Chi-square test in all cases. RESULTS A total of 80 cases were analysed. Significant association of p53 expression was found in higher grades of tumour. Also, noted relation of p53 mutation with tumour size, multifocality, multiplicity, muscle invasion and tumour stage, which were statistically not significant. CONCLUSION Bladder tumour grade shows significant association to p53 expression. Papillary neoplasm of low malignant potential (PUNLMP) tumours are negative for p53, and in the present study, there was significant difference in p53 over expression low-grade papillary UCC compared with PUNLMP. 90% of low-grade papillary tumours were p53 positive. This indicates a crucial role of p53 mutation in further tumour progression from PUNLMP to low-grade UCC. p53 mutation may have a role in transformation of low to high-grade TCC, and in this study, we found increased p53 expression with increased grade. But, though tumour size, multifocality, recurrent tumours and advanced stage show positive relation to p53, the association couldn’t be proved to be statistically significant.