Objective: In this retrospective study, it is examined the patterns of use of intravesical therapy (IVT) in high-grade T1 bladder cancer and the subsequent impact on survival for patients ultimately proceeding to radical cystectomy (RC). Patients and Methods: The study evaluates a total of 104 patients with T1 high-grade transitional cell carcinoma (TCC) and who underwent RC between 1990 and 2005. Patients were divided into two groups; those having RC before 1998 and those after 1998. Trends in time from diagnosis to RC, courses of IVT, recurrence and pathological stage were analysed using two-sample t-tests with 95% confidence intervals. Results: Before 1998, 28 of 38 patients (74%) proceeded directly to RC with no IVT, vs 20 of 47 (43%) after 1998 (P=0.004). The mean number of IVT courses per patient was 0.53 before 1998 and 1.2 afterward (P=0.016). Patients who had RC before 1998 had a 69.7% disease- free survival at 5 years, vs 39.6% for those after 1998 (P=0.05). Conclusion: This retrospective study indicates that patients having RC for T1 high-grade TCC after 1998 were more likely to receive IVT. These same patients had a worsening diseasefreesurvival. The decreasing in survival might be related to an increased use of IVT. The possibility that IVT might be delaying curative surgery.