Diffusion-Weighted MRI Is Insensitive to Changes in the Tumor Microenvironment Induced by Antiangiogenic Therapy

摘要: Antiangiogenic treatment (AAT) used in combination with radiation therapy or chemotherapy is a promising strategy for the of several cancer diseases. The vascularity and oxygenation tumors may be changed significantly by AAT, consequently, noninvasive method monitoring AAT-induced changes these microenvironmental parameters needed. purpose this study was to evaluate potential usefulness diffusion-weighted magnetic resonance imaging (DW-MRI). DW-MRI conducted Bruker Biospec 7.05-T scanner using four diffusion weightings sensitization gradients three orthogonal directions. Maps apparent coefficient (ADC) were calculated monoexponential model. Two cervical carcinoma xenograft models (BK-12, HL-16) treated bevacizumab, two pancreatic (BxPC-3, Panc-1) sunitinib. Pimonidazole CD31 as markers hypoxia blood vessels, respectively, fraction hypoxic tissue (HFPim) microvascular density (MVD) quantified analyzing immunohistochemical preparations. MVD decreased after AAT BK-12, HL-16, BxPC-3 tumors, decrease sufficiently large cause significant increase HFPim BK-12 tumors. ADC maps untreated control not different any tumor models, suggesting that detectable DW-MRI. insensitive induced bevacizumab sunitinib treatment.