Microvascular network in renal carcinomas. Quantitative and tissue microarray immunohistochemical study

The aim of the study was to investigate differences in microvessels between renal tumors. The material consisted of 97 clear cell carcinomas (CCRCC), 20 papillary carcinomas (PapRCC), 33 chromophobe carcinomas and 15 oncocytomas (RO). The endothelia were stained immunohistochemically for CD34 antigen. The vascular features were analyzed with the AnalySIS image processing system. The stains for VEGF, GLUT-1 and Ki67 were performed on tissue microarrays. The mean microvascular density (MVD) was 163.62 profiles/mm2 and microvascular area (MVA) was 3.75%. The highest values were seen in CCRCC and the lowest in PapRCC. The size and shape parameters of the individual vessels were also different between the tumors under consideration. The tumor diameter, MVD and MVA were inversely correlated, the relationship being the strongest for RO. The minimum spanning tree parameters were different between histological types, especially between CCRCC and PapRCC. The mean fractal dimension was 1.32, and similar in all cases. VEGF, Ki67 and GLUT-1 expression was the highest in CCRCC, and lowest in RO. The vascular parameters were correlated with Ki67, GLUT-1 VEGF expression, tumor grade, and inversely correlated with tumor diameter. The relationships in each tumor type were slightly different.