CD44 standard form expression as a predictor of progression in high risk superficial bladder tumors.

Objective: The purpose of this study was to assess the significance of the standard CD44 adhesion molecule expression in predicting progression of high risk superficial bladder carcinoma in the short term.

Methods: Sixty-six patients (51 males and 15 females, aged 27 to 89 years (mean 64.75 years) with primary superficial transitional cell bladder cancer initially treated with transurethral resection (TURBT) were enrolled in the study. Only pTa/pT1 grade 2 multiple tumors as well as all grade 3 tumors were included in this study. All tumor samples obtained after the resection were immunohistochemically evaluated for the expression of the CD44 standard molecule. Fifty eight patients remained during the follow up period which ranged from 3 to 36 months (mean 11.8 months). Tumor progression in the short term was considered as the critical end point of interest in this study. The prognostic significance of tumor stage, grade, presence of carcinoma-in-situ (CIS) and expression of CD44 in determining the risk for progression, was studied with both univariate (log rank test) and multivariate (Cox proportional hazards) methods of analysis.

Results: Kaplan-Meier survival curves indicated that a shorter median progression-free survival is expected for those patients with G3 bladder tumors (p = 0.0055), concomitant CIS (p = 0.0051), and loss of expression of CD44 (p = 0.0015), whereas a similar association with stage was not detected (p = 0.5793). The cox regression multivariate analysis did not yield a significant result for any of the studied parameters therefore no one of the factors taken into account can serve as an independent predictor of progression in superficial bladder cancer in the short term.

Conclusion: The immunohistochemically detectable loss of the expression of CD44 standard form from superficial bladder tumor samples may be, complementary to the established prognostic factors, a useful predictor of tumor progression in the short term.