Breast carcinoma: Vascular density determined using CD105 antibody correlates with tumor prognosis

Angiogenesis is essential for tumor growth and metastasis. There are confli cting reports as to whether microvessel density (IMD) in breast cancers is associated with prognosis, This could be due to the use of different antibo dies to endothelial cell markers, variation in tissue pretreatment protocol s, and nonstandardized counting methods, We have assessed the IMD in 106 br east carcinomas using a pan-endothelial marker, CD34, and a recently descri bed mAb to CD105, which preferentially reacts with endothelial cell in angi ogenic tissues. IMD values (separated as above or below median) for CD105 e xpression showed a statistically significant correlation with overall (P = 0.0029) and disease-free survival (P = 0.0362). In contrast, blood vessel c ounts using a panendothelial marker CD34 did not correlate with overall or disease-free survival (P = 0.2912 and P = 0.3153, respectively). When IMD v alues were subdivided into quartiles and assessed for their prognostic valu es, there was a statistically significant difference in the overall surviva l across CD105, but not CD34, values (P = 0.0017 and P = 0.7997, respective ly) and also disease-free survival (P = 0.0431 and P = 0.5066, respectively ). Further analysis of IMD values demonstrated that there were no deaths in the lowest quartile for CD105 and it differed from the other three quartil es. However, examination of clinical details of patients in the lowest quar tile failed to reveal clustering of patients known to be associated with lo w-risk factors. Multivariate analysis confirmed that IMD values using CD105 were an independent prognostic factor. These results suggest that the abil ity to quantitatively distinguish between tumor neovascularization and pree xisting vessels may be important in the assessment of tumor angiogenesis, b ut requires confirmation in a greater number of patients with a longer foll ow-up.