Molecular Cytogenetics In Exfoliated Cell Of Bladder Cancer And Its Clinical Significance

Background: Transitional cell carcinoma accounts for 90% of bladder cancer and its etiology and mechanism of carcinogenesis remain unknown, the incidence is increasing year after year. Non-random chromosome aberrations are related to the initiation, development and metastases of bladder cancer. Florescence in situ hybridization(FISH), one of the most important molecular cytogenetic techniques, overcomes the main inconvenience in classical cytogenetic methods in solid tumors. A well interpretation of the molecular cytogenetic alterations in exfoliated cells exert great applicable value in the diagnosis, prognosis prediction and follow-up for bladder cancer.Methods: Using centromeric probes of chromosome 7, 9, 11 and 17, FISH examination was performed in urine samples from 34 patients and bladder washings from 30 patients respectively. Flow cytometric analysis was also carried out in each sample as a comparative study.Results: (1) Numerical aberration frequency of chromosome 7, 9, 11, 17 was 23.5%, 38.2%, 14.7% and 11.8% in urine samples and 30.0%, 50.0%, 26.7% and 16.7% in bladder washings respectively. Loss of chromosome 9 was a most common aberration, without relation to pathological grade and stage of bladder cancer, whereas abnormality of chromosome 7 was associated with the stage of bladder cancer, numerical aberration of chromosome 11,17 was not related to grade and stage of bladder cancer.(2) The positive rate examined by cytology, flow cytometry and FISH was 29.4%, 52.9% and 55.9% in urine samples, and 27.6%, 51.7%, 73.7% in bladder washings, respectively. When the three methods were combined, it was separately 82.3% and 83.3% for these kinds of samples.Conclusion: (1) Detection of chromosome aberrations in interphase nuclei of...