Clinical value of aneusomy of chromosomes in exfoliated urothelial cells to predict the recurrence of superficial bladder cancer after complete transurethral resection

Abstract

To analyze the chromosomal karyotype aberrations of exfoliated urothelial cells in superficial bladder cancer patients and the correlation thereof to recurrence of carcinoma. Voided urine samples were collected from 42 patients with pathologically confirmed recurrent bladder cancer and 24 bladder cancer patients without pathologically confirmed recurrence, all of which had undergone complete transurethral resection and had been followed up for more than 3 years. Fluorescence in situ hybridization (FISH) was used with Spectrum Green to label the chromosome 7 and Spectrum Red to label the chromosome 17 of the exfoliated urothelial cells. The aneuploidy rates of chromosomes 7 and 17 were 48.5% (32/66) and 50.0% (33/66) respectively, and the co-aneuploidy rate of chromosomes 7 and 17 was 25.8% (17/66). In the patients with G(2/3) superficial bladder cancer, the aneuploidy rate of chromosomes 17 of those with recurrence was 64.3%, significantly higher than that of patients without recurrence (22.2%, P < 0.05). However, there were not significant differences in the aneuploidy rates of chromosomes 7 and 17 in the pT(a) and pT(1) superficial bladder cancer patients with or without recurrence (all P > 0.05), however, the co-aneuploidy rate of chromosomes 7 and 17 of the patients with recurrence was 47.8%, significantly higher than that of the patients without recurrence (12.5%, P < 0.05). Fourteen of the 42 patients with recurrence showed progression, i.e., with increased grade or stage (>/= pT(2)). The aneuploidy rates of chromosomes 7 and 17 of these 14 patients were 78.6% and 92.9% respectively, both significantly higher than those of the 28 patients without progression (42.9% and 46.4% respectively, both P < 0.05). Abnormality in the chromosomes in exfoliated urothelial cells of superficial bladder cancer patients using FISH technique helps predict recurrence and progression of the cancer.