Objectives. The clinical course of carcinoma in situ (CIS) of the bladder is highly variable. Our objective in this study was to describe E-cadherin expression patterns in CIS with and without papillary disease and to determine whether altered E-cadherin expression is associated with disease progression and survival in patients with CIS of the bladder.

Methods. Tumor specimens from 53 patients who had CIS in the absence of muscle-invasive carcinoma on bladder biopsy were identified. Formalin-fixed paraffin sections were processed using a hot citric acid antigen retrieval method, followed by immunostaining with anti-E-cadherin monoclonal antibody. Expression patterns were evaluated in a blinded fashion and scored as normal and abnormal, which included absent and various degrees of heterogeneous immunostaining. Outcomes analyzed were recurrence, progression, and survival.

Results. Loss of normal membrane E-cadherin immunoreactivity was found in 17 patients (32%). At a median follow-up of 131 months, abnormal E-cadherin expression was significantly associated with disease recurrence (P = 0.0087), disease progression (P = 0.0003), and bladder cancer-specific survival (P = 0.0285). In multivariate analyses, E-cadherin expression was independently associated with disease recurrence (P = 0.019, 95% confidence interval [CI] 1.342 to 5.940), disease progression (P = 0.002, 95% CI 2.049 to 17.989), and bladder cancer-specific survival (P = 0.025, 95% CI 1.179 to 10.432).

Conclusions. Loss of E-cadherin expression in patients with CIS with and without papillary disease of the bladder predicts disease recurrence, disease progression, and bladder cancer-specific death. CIS with and without papillary disease associated with abnormal E-cadherin expression may represent a biologically more aggressive cancer, requiring early definitive therapy. This hypothesis should be evaluated in larger studies and prospective clinical trials.