Impact of variant differentiation on patient survival after radical cystectomy in urothelial carcinoma of the bladder

Abstract

Objective To find out the impact of variant histologic differentiation of patients with urothelial carcinoma of the bladder on survival after radical cystectomy. Methods Between 2006 and 2012, 418 consecutive patients who underwent radical cystectomy with lymphadenectomy for urothelial carcinoma of the bladder were included. The patients were divided into three groups: group A included 262 patients with pure urothrothial carcinoma, group B included 103 patients with squamous and/or glandular differentiation and group 3 comprised 53 patients with non–squamous and/or glandular differentiation. Cancer–specific and overall survivals were compared using Kaplan–Meier method, Log–rank test and multivariable Cox proportional hazard regression analyses. Results Of the 418 patients, 108 were diagnosed with a single variant histology, and 58 had multiple patterns. Squamous differentiation (n=48; 11.5%) was the most common single variant histology, followed by glandular (n=40; 9.6%) and sarcomatoid(n=13; 3.1%). Compared to group A, group B and C were more likely to have advanced tumor stage(pT4 in group B vs group C vs group A: 29, 14, 24; 28.2% vs 26.4% vs 9.2%), lymph node metastases(35, 13, 31; 34.0% vs 24.5% vs 11.8%)and lymphovascular invasion(45, 22, 49; 43.7% vs 41.5% vs18.7%)(P–values<0.017). In univariable analyses, group B and group C were at significantly higher risk for cancer specific mortality and overall mortality than patients with pure UCB (P–values<0.01). In multivariable analyses, group C had significantly prognostic influence in cancer–specific mortality (HR 2.49, 95%CI 1.32–4.67, P<0.01) and overall mortality (HR 2.21, 95%CI 1.31–3.73, P<0.01). Conclusion Variant differentiation was independently associated with adverse outcomes for patients with urothelial carcinoma of the bladder after radical cystectomy. Key words: Urothelial carcinoma; Pathology; Prognosis; Radical cystectomy; Variant