Automatic quantification of microvessel density in urinary bladder carcinoma

Seventy-three TUR-T biopsies from bladder carcinoma were evaluated regardin g microvessel density, defined as microvessel number (nMVD) and cross-secti on endothelial cell area (aMVD). A semi-automatic and a newly developed, au tomatic image analysis technique were applied in immunostainings, performed according to an optimized staining protocol. In 12 cases a comparison of b iopsy material and the corresponding cystectomy specimen were tested, showi ng a good correlation in 11 of 12 cases (92%). The techniques proved reprod ucible for both nMVD and aMVD quantifications related to total tumour area. However, the automatic method was dependent on high immunostaining quality . Simultaneous, semi-automatic quantification of microvessels, stroma and e pithelial fraction resulted in a decreased reproducibility. Quantification in ten images, selected in a descending order of MVD by subjective visual j udgement, showed a poor observer capacity to estimate and rank MVD. Based o n our results we propose quantification of MVD related to one tissue compar tment. When staining quality is of high standard, automatic quantification is applicable, which facilitates quantification of multiple areas and thus, should minimize selection variability. (C) 1999 Cancer Research Campaign.