The association between variant urothelial histologies, pathological stage and disease specific survival in patients with bladder cancer.

OBJECTIVE

We aimed to compare the oncological outcomes of patients with variant urothelial histologies (VH) with pure urothelial histology (PUH) in bladder cancer (BC) patients.

MATERIAL AND METHODS

This study includes 223 patients who underwent radical cystectomies (RCs) between September 2006 and July 2016 with complete follow-up data A retrospective screening was performed to identify the patients with PUH and VH. The primary outcomes of interest were pathological stage of disease at RC and disease-specific survival (DSS). For comparison of categorical variables, Fisher's exact test and Pearson chi- square and for continuous variables Wilcoxon rank-sum and Mann-Whitney U tests were used. Kaplan-Meier (KM) method was used for survival analysis and log-rank test was used for comparison of survival rates. Predictors of survival were detected with mulitivariable Cox-proportional hazards model including the variables such as gender, age, existence of VH, lymph node dissection (LND) type and pathological stage of the disease.

RESULTS

A moderate-degree correlation was detected between VH and pathological stages of RC (r=0.45, p<0.001). In PUH group, 39 (25.8%) of 151 patients died after a median follow-up of 20 (0-107) months; whereas 37 (51.4%) of 72 patients with VH died after a median follow-up of 16.5 (0-104) months (p<0.001). In terms of pathological stage, the number of patients with PUH and VH were at stages pT0-2 (n=100; 66.2% vs. n=19; 26.4%), pT3-4 (n=35; 23.2% vs. 38; 52.8%, and in 16 (10.6%) and 15 (20.8%) patients with LN positivity, respectively (p<0.001). KM survival analysis revealed a significantly decreased DSS in patients with VH compared to PUH (p<0.001). Meanwhile, pathological disease stage and existence of VH were found to be associated with decreased DSS in the multivariate model.

CONCLUSION

The present study revealed that VH is associated with advanced pathological tumor stage at RC and decreased DSS compared to patients with PUH in patients with BC.