Clinical Evaluation of Random Biopsy of Urinary Bladder in Patients with Superficial Bladder Cancer

Background Superficial bladder cancer has a tendency to recur in the urinary bladder. One reason for recurrence is the presence of concomitant carcinoma in situ (CIS) or dysplasia. However, the usefulness of random biopsy of the urinary bladder has been unclear.
Methods Between September 1990 and March 1996, 83 patients with superficial bladder cancer underwent mucosal biopsy of 6 different sites in the urinary bladder with macroscopically normal findings (random biopsy). The relationship between a positive biopsy (CIS or dysplasia) and the tumor characteristics was examined. The disease-free survival of the patients according to the biopsy results was determined.
Results The positive biopsy rate was 24.1% (CIS, 14.5% dysplasia, 9.6%). The incidence of positive biopsy in patients with high-grade (C3), pT1 tumors, 3 or more and non-papillary wide-based tumors was significantly higher than that in patients with 1 or 2 tumors, low-grade (G1, G2), pTa tumors and papillary tumors (P< 0.05). In patients with a single papillary tumor, positive biopsy was found in 9.5%. The disease-free survival in patients with a positive biopsy did not differ from that in patients with a negative biopsy, because intravesical bacillus Calmette-Guérin was instilled in patients with a positive biopsy.
Conclusion Our results indicate that random biopsy is useful for detecting concomitant CIS or dysplasia and in the choice of drugs for intravesical instillation.