Survival after radical cystectomy of non-bilharzial squamous cell carcinoma vs urothelial carcinoma: a competing-risks analysis.

Abstract

•  To test the effect of histological subtype (NBSCC vs UC) on cancer-specific mortality (CSM), after adjusting for other-cause mortality (OCM). •  In Western countries, non-bilharzial squamous cell carcinoma (NBSCC) is the second most common histological subtype in bladder cancer (BCa) after urothelial carcinoma (UC). •  We identified 12,311 patients who were treated with radical cystectomy (RC) between 1988 and 2006, within 17 Surveillance, Epidemiology and End Results (SEER) registries. •  Univariable and multivariable competing-risks analyses tested the relationship between histological subtype and CSM, after accounting for OCM. •  Covariates consisted of age, sex, year of surgery, race, pathological T and N stages, as well as tumour grade. •  Histological subtype was NBSCC in 614 (5%) patients vs UC in 11,697 (95%) patients. •  At RC, the rate of non-organ confined (NOC) BCa was higher in NBSCC patients than in their UC counterparts (71.7% vs 52.2%; P < 0.001). •  After adjustment for OCM, The 5-year cumulative CSM rates were 25.0% vs 19.8% (P= 0.2) for patients with NBSCC vs UC organ confined (OC) BCa, respectively. The same rates were 46.3% vs 49.3% in patients with NOC BCa (P= 0.1). •  In multivariable competing-risks analyses, histological subtype (NBSCC vs UC) failed to achieve independent predictor status of CSM in patients with OC (hazard ratio, 1.2; P= 0.06) or NOC BCa (hazard ratio, 1.1; P= 0.1). •  At RC, the rate of NOC BCa is higher in NBSCC patients than in their UC counterparts. •  Despite a more advanced stage at surgery, NBSCC histological subtype is not associated with a less favourable CSM than UC histological subtype, after accounting for OCM and the extent of the disease (OC vs NOC).