[Study of the angiogenesis as prognostic factor of pT1G3 bladder tumours]

Angiogenic activity has been considered like prognostic factor in several solid tumors. This activity can be analysed by two ways: immunohistochemical determination of molecules that activate/inhibit angiogenesis or quantitive measure of microvascular density (MD). Our objective is to determine the prognostic value of Vascular Endothelial Growth Factor (VEGF) and Microvascular Density (MD) in pT1G3 bladder tumours.

We have studied retrospectively 83 patients with pT1G3 tumors treated by TUR + endovesical instillations with a follow up of 3 years at least. We analysed VEGF expression monoclonal antibody No. 360P. To determine MD we have marked vessels with FVIII antibody and detected "hot spots" areas. The number of microvessels is quantited by a digital image analyser excluding those that have more than 50 micras of diameter. We established the correlation of these findings with recurrence, progression and survival by using Chi-square test and Kaplan-Meier curves (log-rank).

Average follow up was 58 +/- 28 months. We have established like cut-off 50% of tumor cells (VEGF) and 30 microvessels/fields (MD). Chi-square test did not show correlation with survival neither recurrence but it was positive for progression p(VEGF) 0.048 and p(DM) 0.021. Kaplan Meier curves determined significative differences only for free of progression time respect to MD (p 0.038).

We did not find statistically significant value for recurrence nor survival. Just MD reached prognostic value for progression. More studies and multivariant analysis are required to determine the clinical utility of MD, specially in order to make more aggressive therapeutic options in this kind of patients.