Prognostic value of CD44s expression in urothelial bladder tumors.

Urothelial bladder carcinoma (UBC) includes a large group of malignancies with a variable clinical behavior. Despite remarkable developments in recognition of bladder carcinogenesis and prognostic factors, the recurrence rate is still high. Thus, identification of novel biomarkers involved in tumor cell invasion and metastatic dissemination is a constant challenge. AIM To assess the prognostic impact of CD44 standard (CD44s) expression in UBT. METHODS We assessed the immunohistochemical expression of CD44 in 38 samples of endoscopically resected UBT. Only membranous staining was considered positive. We analyzed topographic distribution of CD44s staining. Correlation of CD44s expression, clinicopathological features and disease progression was analyzed by Chi2 and Fisher tests. Kaplan-Meier analysis was used to investigate CD44s prognostic value. RESULTS The mean age of patients was 61,24 years with male to female ratio of 18/1. CD44s expression was positive in 33 cases (87%). There was no significant correlation between CD44 expression and the parameters:  age, gender, tumor size, focality, tumor site, stage, recurrence and tumor progression. CD44s loss of expression is, nevertheless, correlated with a high tumor grade. Topographic distribution of CD44s staining was associated with focality, grade and stage. Basal/parabasal staining expanded to the tumor layers in homogeneous "laminate" pattern used to be of better prognosis, compared to the heterogeneous "islets" or "dispersed" pattern. CONCLUSIONS Our results highlighted the prognostic value of CD44 expression in UBT. Focusing especially on staining pattern offers a better understanding of bladder carcinogenesis mechanisms.