Long-Term Efficacy of Intravesical Bacillus Calmette-Guerin for Carcinoma in Situ: Relationship of Progression to Histological Response and p53 Nuclear Accumulation

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Abstract
Purpose: We assessed the influence of the histological response to intravesical bacillus Calmette-Guerin (BCG) and the prevalence of p53 nuclear accumulation on the clinical behavior of patients with carcinoma in situ. Materials and Methods: Of 60 patients with Bergquist grade 3 carcinoma in situ 13 had primary and 47 had secondary carcinoma in situ. Patients received 6 weekly instillations and nonresponders received an additional 6 instillations at 2-week intervals. No maintenance was administered. Median followup was 48 months. The p53 nuclear accumulation was detected by immunohistochemical analysis with antibody PAb 1801. Results: The complete histological response rate to BCG therapy was 64%, which decreased to 52% at 4 years. BCG was more effective for treatment of primary than secondary carcinoma in situ (complete response rate 85 versus 57%, respectively). The 45% progression rate was related to the initial histological response occurring in 26% of patients with a complete versus 77% with a partial and no response. Consequently, the progression rate was only 8% for primary versus 57% for secondary carcinoma in situ. Of the patients receiving only 1 course of BCG 40% had progression compared to 62% of those who received 2 courses. Patients in whom both courses failed had a progression rate of 89%. Intravesical BCG converted the p53 nuclear immunoreactivity from positive to negative in 73% of the 26 patients expressing reactivity before treatment, of whom 68% also had a complete response. The progression rate was related to the prevalence of p53 nuclear reactivity after but not before treatment (90% of patients with versus 37% without p53 nuclear accumulation had progression). All 3 complete responders with p53 nuclear reactivity after BCG had progression, which suggests that molecular genetic change may precede histological change. Complete responders without p53 nuclear accumulation after BCG treatment experienced the lowest progression rate (21%). Conclusions: Our results suggest that patients with a persistent complete histological response and without p53 nuclear accumulation after BCG treatment can be followed conservatively. Cystectomy should be considered in all other patients.