Urine or bladder washings in the cytologic evaluation of transitional cell carcinoma of the urinary tract. A comparison made under routine conditions supplemented by flow cytometric DNA analysis.

The usefulness of urine and bladder washings for cytological purposes and routine conditions was compared in a reevaluation of 192 specimens from urothelial tumors. To supplement the cytological interpretation by more objective means urine and bladder washings from the same tumours were analyzed by flow cytometry. The cytological reevaluation demonstrated the necessity for extensive experience in this kind of material. No real difference was noted between urine and bladder washings in the cytological interpretation but bladder washings were superior to urine in displaying aneuploidy. The results illustrate the need for a precise sampling technique and for the supportive role of flow cytometry in the management of urothelial tumors.