Multivariate evaluation of factors affecting recurrence, progression, and survival in patients with superficial bladder cancer treated with intravesical bacillus Calmette-Guérin (Tokyo 172 strain) therapy: significance of concomitant carcinoma in situ.

ABSTRACT

To evaluate the relative importance of clinicopathological factors affecting recurrence, progression, and survival in patients with superficial bladder cancer (pTa and pT1) undergoing bacillus Calmette-Guerin (BCG) therapy (Tokyo 172 strain), we reviewed data for 146 patients treated between 1985 and 1998. The median follow-up period was 64.7 months. Tumour recurrence, progression, and death were evaluated as endpoints using Cox's proportional hazards model. The 5-year recurrence-free rate was 56% for all 146 patients. Those with a past history of bladder cancer (n = 73) had significantly earlier recurrence than those without (n = 73, p = 0.017) and this tended to be the case for concomitant CIS (n = 34) although this did not reach statistical significance. The 5-year progression rate was 15% for all 146 patients and univariate analysis revealed that the presence of concomitant CIS was significantly associated with disease progression (p = 0.002). Multivariate analysis using the proportional hazards model confirmed the finding that only one factor, concomitant CIS, was significantly associated with progression. The 5-year survival rate was 84% for all 146 patients. Furthermore, univariate and multivariate analyses revealed that patient age, history of bladder cancer, and concomitant CIS were variables significantly related to patient survival. The present findings suggest that careful follow-up is mandatory after BCG instillation therapy for patients with superficial bladder cancer and concomitant CIS because of their relatively poor prognosis.