[Clinicopathological characteristics of micropapillary variant of urinary bladder carcinoma]

Micropapillary urothelial carcinoma (MUC) is a rare variant of urinary bladder carcinoma associated with highly aggressive behaviour. The aim of this study was to analyse clinicopathological features of MUC particularly a relationship between pathological stage at presentation and proportion of micropapillary component (MPC) in 10 patients with MUC. In the examined period (January 1st 2004 - June 30th, 2007) there were 610 patients with urinary bladder cancer (M:F = 456:154), while 10 (1.6%) of them were patients with MUC. All MUC were invasive at the time of diagnosis. Stage distribution at presentation was 4 T1(40%) and 6 T2 (60%) and the percentage of MPC correlated with pathological stage: 3 of 4 (75%) tumors staged T1 had less than 10% of MPC and 5 of 6 (83,3%) tumors staged T2 had more than 50% of MPC. MUC is an aggressive tumor, often in advanced stage of disease at the time of diagnosis, in which the pathological stage is related to the proportion of MPC.