LAUSR

BACKGROUND Controversy still exists regarding efficacy of multimodality treatment (MMT) vs. radical cystectomy (RC) for urothelial carcinoma of the urinary bladder (UCUB). METHODS Within the SEER database (2004-2016), we retrospectively identified patients with stage T2N0M0 UCUB. Competing risks regression (CRR) tested cancer-specific mortality (CSM) and adjusted for other-cause mortality after MMT vs. RC. Exact matching for age was applied. Subgroup analyses focused on differences in chemotherapy or lymph node dissection rates. In sensitivity analyses, we accounted for 40% understaging rate in patients who underwent MMT. RESULTS Of 9862 patients with T2N0M0 UCUB, 2675 (27.1%) underwent MMT vs. 5751 (58.3%) RC vs. 1436 (14.6%) radiotherapy (RT) without chemotherapy. MMT rate increased (annually +3.0%, P < .01) and MMT patient age was significantly higher (median 77 years) than RC patient age (68 years). In exact age-matched analyses, 10-year CSM rates were 44.3% vs. 25.9% for MMT vs. RC (multivariate hazard ratio [HR] 0.48); 44.1% vs. 22.8% for MMT vs. RC with chemotherapy (HR 0.43); 40.5% vs. 31.1% for MMT vs. RC without lymph node dissection (HR 0.66), and 55.6% vs. 27.3% for RT without chemotherapy vs. RC (HR 0.37, all P < .001). Sensitivity analyses that addressed understaging of patients who underwent MMT resulted in virtually the same CSM rates. CONCLUSION In patents with T2N0M0, MMT or even more so RT alone may be associated with higher CSM than RC, even in exact age-matched multivariate CRR analyses, which adjust for other-cause mortality. In consequence, patients with T2 UCUB should be informed of this possible CSM disadvantage outside of highly specialized centers.