Early results of the value of p53 in predicting survival in a homogeneous cohort of patients with invasive bladder cancer treated with a neoadjuvant carboplatin-based regimen (M-CAVI).

AIMS AND BACKGROUND

Several reports on prognostic factors for infiltrating-bladder cancer have given controversial results. We assessed the prognostic value of p53 nuclear overexpression together with known prognostic factors for survival in patients with invasive T2-4 N0 M0 bladder cancer treated with neoadjuvant chemotherapy.

STUDY DESIGN

Thirty-five paraffinized tumor samples from initial transurethral resection of patients with bladder cancer were analyzed immunohistochemically to detect overexpression of p53 protein. Patients were treated with 3 to 4 cycles of neoadjuvant methotrexate, carboplatin, and vinblastine (M-CAVI) and then underwent radical cystectomy. Prechemotherapy, treatment, and postchemotherapy factors were analyzed for correlation with survival by univariate and multivariate analysis. Fifty-seven percent of tumors were positive for p53 protein, 71.5% had grade III-IV tumors, and 72% had organ-confined disease. The median follow-up was 20 months (range 5-71+).

RESULTS

By univariate analysis, the significant pretreatment factors were initial tumor (T) stage (P < 0.0001) and the male sex (P = 0.03). Five postchemotherapy variables were found significant: surgery performed according to protocol (P = 0.003), overall clinical (P = 0.004), and overall pathologic (P = 0.02) response to therapy, postchemotherapy pathologic stage (P = 0.0002), and tumor status after surgery (P = 0.0006). By multivariate analysis, the initial prechemotherapy T stage was the only factor that demonstrated independent significance.

CONCLUSIONS

Although the median follow-up of the study is still too short, in this group of patients treated with a neoadjuvant carboplatin-based regimen, a classical variable (prechemotherapy T stage) rather than p53 nuclear overexpression was an independent prognostic factor for survival. Further follow-up will be required to assess the value of p53 overexpression as a prognostic factor in invasive bladder cancer patients treated with neoadjuvant carboplatin-based chemotherapy.