Many studies have indicated that nuclear DNA content evaluation can be used to predict biological behavior of transitional cell carcinoma (TCC) of the bladder. Some authors also indicated that static cytometry is more useful in DNA content analysis than flow cytometry. The aim of the present study was to evaluate the prognostic significance of DNA ploidy in TCC of the bladder, performed by using static cytometry with an image analyzer, and monitoring patients at 10 years follow-up. Thirty-one consecutive patients underwent transurethral or open surgery for bladder tumors, and neoplastic tissue samples taken from each patient were imprinted on glass slides and sent for histopathological and DNA content evaluation. DNA ploidy evaluation was performed using a CAS 200 image analyzer. Nuclear DNA content evaluation was compared to patient follow-up on recurrence, progression or survival performed 10 years after surgery. Pathological evaluation demonstrated the presence of superficial TCC in 23 patients, while 8 had an invasive bladder tumor. Twenty-nine tumor samples were adequate for DNA content measurement, with 13 showing diploid DNA content and 16 with aneuploid DNA content. At 10 years follow-up, all patients with aneuploid DNA content demonstrated a lower survival time (p=0.049) and higher recurrence rate (p=0.0346). A log-rank test demonstrated that stage, grade and nuclear DNA content are the most useful prognostic parameters for predicting the biological behavior of TCC of the bladder. These results confirm that static cytometry is a good and reliable method to evaluate DNA tumor content and considered a useful prognostic parameter for predicting recurrence rate, disease progression or survival in patients affected by bladder tumors.