Large nested variant of urothelial carcinoma: a clinicopathological study of 36 cases.

Despite the bland cytological appearance and deceptive pattern of invasion of the LNUC, our study validates its fully malignant potential with metastatic spread and tumour-related deaths. Distinguishing mixed from pure LNUCs seems to be of value. LNUCs show comparable immunophenotype to both conventional urothelial carcinoma and the nested variant of urothelial carcinoma.