Pathological variants of invasive bladder cancer according to their suggested clinical significance.

Several pathological variants of bladder cancer, reflecting tumour heterogeneity in urothelial carcinoma, have been recently recognized. In this review we summarize the most common pathological variants of urothelial carcinoma, with an emphasis on clinical implications. It is important for both pathologists and urologists to be aware of the diverse morphological patterns in invasive bladder cancer, as they might be relevant in patient management and prognosis, mainly because they can mimic benign lesions, secondary tumours or might require a specific therapeutic approach.