RESUMO
OBJECTIVE: To introduce computer-based analysis of Feulgen-stained urinary bladder cell nuclei from voided urine to identify neoplastic urothelial nuclei. STUDY DESIGN: Nuclei from 23 healthy people and 33 patients with urinary bladder cancer were analyzed. The nuclei from 9 cancer patients with grade G1 (stage Ta), 17 with grade G2 (stages Ta, T1, T1a and T2) and 7 with grade G3 (stages Cis, Ta + Tis, T1 and T3b) were analyzed. Image analysis was carried out by means of a digital image processing system designed by the authors. Features describing nuclei were selected as the first step of the procedure. Then a multistage classifier was constructed to identify positive and negative cases. RESULTS: The results of this pilot study of a group of 56 patients yielded a 71% correct classification rate in the control group, while a 66% rate was obtained among the cancer patients. The sensitivity of the method was 100% and the specificity was 77%. CONCLUSION: This approach to the identification of neoplastic urothelial nuclei may be sufficiently well developed to be used successfully both in screening high-risk populations and in clinical practice.