Background: T1 high-grade non-muscle invasive bladder cancer has a high recurrence rate and progression. The treatment options have some controversy.

Objective: To evaluate the progression of T1 high-grade non-muscle invasive bladder cancer in Ramathibodi Hospital and determine the prognostic factors that contribute to muscle invasive disease.

Materials and Methods: The authors retrospectively reviewed 70 patients diagnosed as T1 high-grade bladder cancer from 1,270 bladder cancer patients in Ramathibodi Hospital between 2007 and 2017. The primary objective was to evaluate the progression rate and related prognostic factors. The authors analyzed the risk factors contributing to the progressive muscle invasive disease. The authors also analyzed the survival rate between the progressive group and the non-progressive group. Finally, the role of early cystectomy in T1 high-grade bladder cancer was also analyzed.

Results: The mean age was 68 years old and the mean follow-up time was 40.1 months. The recurrence rate was 55.7% (39/70). The risk factors of recurrence were no muscle at the initial tumor resection and history of intravesical BCG instillation before diagnosis of T1 high-grade cancer. The progression rate was 14.3% (10/70). There was no significant risk factor contributing to progressing the disease. The median survival of non-progressive group was 45.2 months and progressive group was 18.2 months (p=0.002). The authors performed early radical cystectomy in 14 patients and there was no difference in overall survival between the non-progressive disease group and the early cystectomy group.

Conclusion: Lack of muscle at the initial resection and prior intravesical BCG instillation were the risk factors of the recurrence of T1 high-grade bladder cancer. It is obvious that progressive disease is the strongest impact on survival and early radical cystectomy does not improve survival if it was the non-progressive disease. Further studies are needed to identify the risk factors that can differentiate between non-progressive and progressive disease.

Keywords: T1 high-grade non-muscle invasive bladder cancer, Progression, Early radical cystectomy

Received 18 Nov 2018 | Revised 15 Jan 2019 | Accepted 28 Jan 2019