E-cadherin immunoreactivity correlates with recurrence and progression of minimally invasive transitional cell carcinomas of the urinary bladder.

E-cadherin is a transmembrane glycoprotein involved in intercellular adhesion. Abnormal (i.e., lost or decreased) expression of E-cadherin has been linked to invasiveness of many malignant tumors, including bladder carcinomas. To our knowledge, studies analyzing the prognostic impact of E-cadherin immunoreactivity especially in minimally invasive transitional cell bladder carcinomas (stage pT1) have not been published in the Anglo-American literature. In the present study, we immunostained 69 cases of pT1 transitional cell bladder carcinomas for E-cadherin using multitissue arrays. The results were compared with p53 and Ki-67 antigen immunoreactivity, clinicopathological parameters and the patients' outcome. E-cadherin immunoreactivity, which was found abnormal in 42% of cases, correlated significantly with substage (pT1a/pT1b; p=0.029) and p53 index (p=0.041) and tendentiously with Ki-67 antigen index (p=0.089) and age (p=0.07). By univariate Cox regression analysis, abnormal E-cadherin immunostaining correlated significantly (p=0.005) with early tumor recurrence, but not with early tumor progression (p=0.168). In a multivariate analysis, this parameter was identified, besides tumor grade (p=0.002), as an independent predictor of recurrence-free survival (p=0.016). Concerning tumor progression, age was identified as the single independent prognostic parameter (p=0.041), but E-cadherin immunoreactivity displayed a tendentious independent predictive value in this respect (p=0.071). We conclude from our data that immunohistochemical E-cadherin staining may provide additional prognostic information in patients with pT1 bladder carcinomas.