FLUORESCENCE IN-SITU HYBRIDIZATION IDENTIFIES MORE AGGRESSIVE TYPES OF PRIMARILY NONINVASIVE (STAGE PTA) BLADDER-CANCER

Purpose: We evaluated the genetic changes in cytological specimens of bladder cancer by fluorescence in situ hybridization, and related them to stage and grade of the tumor, ploidy, p53 and Ki-67 expression, an d clinical outcome to determine a simple method to identify tumors wit h a poorer prognosis. Materials and Methods: Using fluorescence in sit u hybridization the numerical aberrations of chromosomes 7, 9 and 17 i n barbotages and imprints of 50 patients with transitional cell cancer of the bladder were determined. Of the patients 29 had a primary stag e pTa tumor, while 21 with stage pT1 or greater disease formed the con trol group. Data were compared to ploidy status, and Ki-67 and p53 imm unoreactivity. Results: Repeated monosomy 9 and haploid or diploid sta tus on static ploidy determination were found in patients with primary stage pTa tumors without recurrence. Immunoreactivity of p53 was nega tive in all of these patients, while there was a low percentage of pos itive staining for Ki-67. Patients with recurrent and progressive dise ase had a high incidence of trisomy 7 and 17, aneuploid status and hig h positivity for both immunological markers. For chromosomes 7 and 17, and ploidy status bivariate analysis showed a significant difference. Conclusions: The evaluation of chromosomal aberrations in barbotage a nd imprint specimens clearly establishes a relationship between chromo somal defects and aggressiveness of the tumor. The majority of nonaggr essive stage pTa transitional cell carcinomas can be distinguished fro m potentially lethal cases by fluorescence in situ hybridization at a diagnostic point when the grading is not yet prognostic.