Article Type

Original Study


Objective The aim of this study was to evaluate the diagnostic value of vimentin expression for differentiation between muscularis mucosa (MM) and muscularis propria (MP) in urinary bladder carcinoma cases. Background The single most important prognostic factor in urothelial carcinoma is the pathological stage, which includes the anatomic depth of invasion on which major therapeutic decisions are made. Correct assessment of invasion necessitates discrimination between MM and MP. Vimentin is the most widely distributed intermediate filament and is expressed in virtually all mesenchymal tissues. Materials and methods This study was carried out on 70 urinary bladder specimens, including 59 cases of primary urinary bladder carcinoma and 11 cystitis specimens. The specimens were submitted to vimentin immunostaining under the streptavidin–biotin amplified system. Results MM was identified histologically in 40 cases, whereas MP was morphologically designated in all cases (70 cases). Vimentin was negative in MP and showed positive expression in 32/40 (80%) cases of MM with a statistically significant difference (P = 0.000), 80% of sensitivity, and 100% of specificity. Conclusion Negative vimentin expression in MP could be a useful tool for identification of MP with 80% of sensitivity and 100% of specificity in urinary bladder carcinoma cases.