Microvessel density in invasive breast cancer assessed by dynamic gd‐dtpa enhanced MRI

Abstract
It has been postulated that the rapid enhancement demonstrated by breast carcinomas after administration of contrast media is a direct result of tumor angiogenesis. However, to date, little quantitative data have been published to support this view. A retrospective study has been undertaken to compare dynamic contrast‐enhanced data obtained from 40 patients with microvessel density (MVD) evaluated in specimens immunohistochemically stained with a factor VIII related antigen. The dynamic data were analyzed quantitatively using both simple indices of enhancement and a two‐compartment kinetic model. A moderate but significant correlation was demonstrated between initial enhancement and MVD, and this correlation strengthened when node‐positive tumors were considered in isolation (r = .77, P < .0005). However, the data showed considerable variability. The enhancement characteristics of the tumors could not be explained solely by their MVD; therefore, MRI cannot be used to predict MVD in vivo. Further work is required to address the exact relationship between contrast‐enhanced MRI and tumor angiogenesis.