Clinical Outcomes of Patients With T1 Nested Variant of Urothelial Carcinoma Compared to Pure Urothelial Carcinoma of the Bladder.

PURPOSE: Evaluate oncologic outcomes of patients with cT1 nested variant (NV) of urothelial carcinoma (UC) and compare with cases of pure UC of the bladder.
MATERIALS AND METHODS: We retrospectively identified 30 patients with NV who, between 1997 and 2012, underwent transurethral resection with T1 tumor stage, followed by restaging transurethral resection within 3 months confirming non-muscle-invasive disease. Radical cystectomy within 3 months of restaging transurethral resection was considered "early" treatment. We matched 3 patients with pure UC to each nested patient.
RESULTS: Median follow-up for survivors was 4.3 years from T1-staged transurethral resection. Patients with NV had no statistically significant difference in metastasis-free survival (P = .2) and cancer-specific survival (P = .2) compared with patients with pure UC. However, it is concerning that the rate of upstaging to bladder and/or lymph nodes was 54% in patients with NV who underwent early radical cystectomy, even after rigorous restaging.
CONCLUSIONS: Although NV UC may be diagnosed at a higher stage, when stage matched we have not seen any statistical evidence that it is more aggressive than typical UC. Because patients with NV UC who are cT1 on restaging transurethral resection appear to have a higher propensity to develop nodal metastatic disease and a higher rate of upstaging, patients with cT1 NV UC on restaging biopsy may benefit from "early" radical cystectomy, whereas patients with <cT1 on restaging may be considered for conservative management.