Microsatellite analysis of urine sediment versus urine cytology for diagnosing transitional cell tumors of the urinary bladder.

The aim was to evaluate microsatellite analysis of urine sediment (MAUS) as an alternative method to urine cytology for routine diagnosis of patients with transitional cell tumors (TCT) of the urinary bladder. Urine cytology has the advantage of being non-invasive, fast and cheap, but is of limited value because of its low sensitivity. MAUS has previously been found to be a successful alternative method. However, the experimental set-up of such investigations implied exclusion of samples with unfavorable characteristics and use of a large number of markers. In the present study, MAUS was tested on all samples routinely available and a small panel of markers was selected. The urine sediments of 66 TCT patients and 24 controls were analyzed by MAUS with 16 fluorescent markers and by urine cytology. All samples were analyzed, including the ones of later micturition, with gross hematuria, leukocyturia or absence of visible sediment. In patients with tumors of low grade (grades I-II), MAUS was significantly more sensitive than urine cytology. The two methods were of equivalent diagnostic power in high-grade (grades III-IV), high-stage (pT1-pT4) tumors. A panel of the six most informative markers for MAUS was selected. Although MAUS has an advantage over routine cytology in low-grade, low-stage tumors, an overall sensitivity of 45% is not sufficient for routine clinical use.