Correlation between microvascular density and perfusion parameters derived from dynamic contrast-enhanced computed tomography in dogs with tumors of the head

Abstract

Non-resectable tumors of the head can represent a therapeutic challenge in dogs and prognostic indicators and markers of response to treatment are needed. Tumor microenvironment, in particular microvascular density (MVD), affects response to treatment and prognosis. Perfusion parameters obtained from dynamic contrast-enhanced computed tomography (DCECT) have been correlated to MVD and outcome in humans. Twenty-five dogs comprising 16 epithelial tumors and 9 mesenchymal tumors of the head were prospectively recruited and underwent DCECT. Microvascular density (anti-Factor VIII) was assessed using a trained object classifier in stroma and tumor tissue. Mesenchymal tumors had significantly higher percentage area of blood vessels in tumor tissue than epithelial tumors (P = .04). There was no significant association between perfusion parameters and MVD measurements. These findings suggest that mesenchymal tumors have a higher MVD than epithelial tumors, and that perfusion parameters derived from DCECT might not be well correlated with MVD in dogs with tumors of the head.