Objective: To report on tumour angiogenesis and its relationship with morphological variables and prognosis in adenocarcinoma of the urinary bladder associated with schistosomiasis.
Patients and methods: Fifty-five vesical adenocarcinomas were evaluated from 30 men and 25 women (mean age 47.2 years, sd 8.7, range 30-65) who were followed up after radical cystectomy and urinary diversion for a mean (sd, range) of 61 (43.5, 2.7-159.5) months. Vessels were stained immunohistochemically using an antibody to the platelet endothelial cell-adhesion molecule CD31. Microvessels were counted in active areas of angiogenesis within the tumours (at x250) and the microvessel density (MVD) quantified using the mean of three counts. Treatment failure was defined as death from cancer or the development of local recurrence or distant metastasis. Kaplan-Meier survival curves and Cox's proportional hazard model were used to assess survival.
Results: The overall 5- and 10-year survival rates were 57% and 51%, respectively. The presence of lymph node metastasis and high mean vascular density (> 26) were significantly associated with a poor prognosis. The 5-year survival for patients with negative lymph nodes was 66% while no patients with positive nodes survived for 5 years (P < 0.001); the survival was 72% for patients with a low MVD and 33% for those with a high MVD (P = 0.0016). From individual results plotted against vascularity in lymph node-negative patients, there was a significantly better outcome for those with a low MVD (< or = 26; P = 0.0099); this significance was maintained on multivariate analysis. However, there was no significant relationship between angiogenesis and the different clinicopathological factors apart from the grade (P = 0.03); tumour stage, grade and DNA profile had no significant effect on survival in these patients.
Conclusions: These findings suggest that assessing angiogenesis using the MVD provides an independent predictor of survival in patients with adenocarcinoma of the urinary bladder.