Objective: We evaluated the DNA cytophotometry in 446 bladder washing samples from 64 patients under mitomycin C after superficial bladder cancer during an observation period of up to 5 years. The aim of the study was to identify patients at high risk of recurrence despite chemotherapy-induced atypical, hence noninformative cytology.
Methods: The prognostic value of cytology and ploidy during chemotherapy was compared with regard to recurrence rates and the median time to recurrence.
Results: Aneuploidy identified 8 of 10 patients recurring within 12 months out of 17 patients with atypia at first presentation after surgery, whereas no recurrence was seen after atypia and diploid histograms (p = 0.005, mean follow-up period 62 months). Aneuploidy was the most accurate indicator of short-time recurrence (p < 0.001 by multivariate analysis). Follow-up data showed a relative risk of recurrence of 12.7 following histogram shifts towards aneuploidy and of 1.6 for positive shifts in cytology.
Conclusion: Cytophotometry is superior to cytology in predicting the outcome in patients under chemotherapy for superficial transitional cell cancer of the bladder.