Diagnosis of T1 bladder transitional cell carcinoma by denaturing gradient gel electrophoresis urinalysis.

Objective: The diagnosis and follow-up of patients with T1 bladder cancer relies invasive procedures. We developed a non-invasive method for detection of T1 bladder cancer based on a feasible non-radioactive molecular approach.
Materials and Methods: Urine DNA samples were collected from 24 patients with T1 transitional cell carcinoma (TCC) of the bladder and were processed by denaturing gradient gel electrophoresis (DGGE) analysis. Urine samples obtained from 10 individuals with no clinical evidence of genitourinary malignancy were used as controls.
Results: Ten patients out of 24 (41%) had p53 mutations in their tumor samples. Seven of these presented the same mutation in matched urine samples. The p53 mutation pattern found in urine was always identical to that identified in the primary tumor. Decision diagnostic criteria showed that molecular screening by DGGE of amplified DNA from urine sediment had 69.2 % sensitivity, 100% specificity, 95.8 % accuracy, 100% prediction of positive result and 95.4 % prediction of negative result, respectively. No p53 mutation was found in the urine from control subjects.
Conclusion: DGGE analysis of urine samples could be a useful tool for the early detection of T1 bladder cancer or its recurrence, potentially leading to a reduction in the frequency of invasive procedures used for the management of this disease.