[Clinical significance of multiple biopsies of nontumorous bladder mucosa in patients with bladder cancer].

Multiple biopsy specimens obtained from nontumorous bladder mucosa were investigated histologically. An average of 3.6 specimens was taken in 142 transurethral resection operations for 112 patients with bladder cancer. The histological categories used were normal epithelium, metaplasia, hyperplasia and G1-G3 dysplasia. Thirty-seven patients (27.7%) had G2 less than dysplasia within normal looking bladder mucosa. In patients with high grade bladder cancer, the incidence of the association with dysplasia was 51.7%, which was significantly higher than the rates in patients with low or moderate grade bladder cancer (p less than 0.05). The tumor recurrence was observed in 45 patients of 102 patients who were followed with bladder preservation. The recurrence was seen in 13 of 19 patients (68.4%) with mucosal dysplasia in the previous operation. The rate was significantly higher than 38.6% in patients without dysplasia (p less than 0.05). Thus, the epithelial dysplasia seen in nontumorous bladder mucosa were associated with higher grade bladder tumors more often, and the histology of multiple biopsy specimens might be one of predictors for tumor recurrence in near future.