Proliferative activity is the most significant predictor of recurrence in noninvasive papillary urothelial neoplasms of low malignant potential and grade 1 papillary carcinomas of the bladder.

BACKGROUND: Recurrence of transitional cell carcinoma of the bladder cannot be predicted accurately by traditional criteria alone. This study examined the value of cell proliferative activity, morphometry, and expression of p53, c-erbB-2, and bcl-2 oncogenes in predicting recurrence of superficial papillary urothelial neoplasms of low malignant potential (LMP) and Grade 1 (G1) papillary carcinomas of the bladder. METHODS: Sixty-two patients (mean age, 62 years) with newly diagnosed superficial pTa bladder tumors (19 LMP, and 43 G1) were analyzed retrospectively. All patients underwent transurethral resection (TUR). Median follow-up was 69 months. Serial sections from formalin-fixed, paraffin-embedded material at initial TUR were stained with monoclonal antibodies (MoAbs) DO7, CB11, and bcl-2-124. Cell proliferation was assessed by MIB-1 MoAb, the quantity of argyrophilic nucleolar organizer region-associated proteins (AgNORs), and mitotic count. RESULTS: Of the 62 patients, 42 (67.7%) had one or more recurrences. Recurrence rates were higher in MIB-1 (P < 0.0001) and p53 immunopositive cases (P = 0.02), when the mitotic count was greater than 5 (P = 0.004), and in G1 carcinomas (P = 0.04). In univariate analysis, the disease-free period was shorter for MIB-1 (P < 0.0001) and p53 immunopositive (P = 0.0001) cases, for cases with high AgNOR quantity (P = 0.04), mitotic count greater than 5 (P = 0.01), and in G1 carcinomas (P = 0.002). In multivariate analysis, only MIB-1 immunoreactivity retained independent prognostic significance. CONCLUSIONS: Despite the small cohort, the results confirm the prognostic value of cell proliferation and p53 expression in patients with bladder neoplasms. The results also indicate that MIB-1 immunopositivity is the most significant predictor of recurrence and disease-free survival in superficial LMP and G1 papillary bladder carcinomas.