Non-muscle-invasive high-grade (T1G3) bladder cancers have high potential for progression. The objective of this study is to clarify the clinicopathological factors affecting the outcome of T1G3 bladder cancer.

We retrospectively reviewed 60 cases of T1G3 bladder cancer between 1994 and 2006. The correlations of both intravesical recurrence and progression with prognostic factors, such as T stage, history of bladder cancer, multiplicity, concomitant carcinoma in situ, tumor size, intravesical instillation of bacillus Calmette–Guérin and intravesical chemotherapy, were evaluated by multivariate analysis with the Cox proportional hazards model.

Median follow-up period was 52 months (4–105 months). Thirty-seven cases of intravesical recurrence (61.7%) were observed during follow-up. Two- and 5-year recurrence-free survival rates were 44.1% and 36.1%, respectively. Tumor multiplicity and instillation of bacillus Calmette–Guérin were significantly correlated with intravesical recurrence on multivariate analysis. Ten cases of progression (16.7%) were observed during the follow-up period. Two- and 5-year progression-free survival rates were 87.7% and 83.4%, respectively. Only tumor multiplicity was significantly correlated with progression on multivariate analysis.

T1G3 cancers with multiple lesions showed high risks of intravesical recurrence and progression. Although bacillus Calmette–Guérin instillation reduced the risk of intravesical recurrence, no effect was observed on disease progression.