Enhancing fraction in glioma and its relationship to the tumoral vascular microenvironment: A dynamic contrast-enhanced MR imaging study

AJNR Am J Neuroradiol. 2010 Apr;31(4):726-31. doi: 10.3174/ajnr.A1925. Epub 2009 Dec 17.

Abstract

Background and purpose: EnF is a newly described measure of proportional tumor enhancement derived from DCE-MR imaging. The aim of this study was to assess the relationship between EnF and the more established DCE-MR imaging parameters: K(trans), v(e), and v(p).

Materials and methods: Forty-two patients with 43 gliomas (16 grade II, 3 grade III, and 24 grade IV) were studied. Imaging included pre- and postcontrast T1-weighted sequences through the lesion and T1-weighted DCE-MR imaging. Parametric maps of EnF, K(trans), v(e), and v(p) were generated. Voxels were classified as enhancing if the IAUC was positive (EnF(IAUC)(60>0)). A threshold of IAUC > 2.5 mmol.s was used to generate EnF(IAUC)(60>2.5). Both measures of EnF were compared with the DCE-MR imaging parameters (K(trans), v(e), and v(p)).

Results: In grade II gliomas, EnF(IAUC60>0) and EnF(IAUC60>2.5) correlated with v(p) (R(2) = 0.6245, P < .0005; and R(2) = 0.4727, P = .003) but not with K(trans) or v(e). In grade IV tumors, both EnF(IAUC60>0) and EnF(IAUC60>2.5) correlated with K(trans) (R(2) = 0.3501, P = .001; and R(2) = 0.4699, P < .0005) and v(p) (R(2) = 0.1564, P = .01; and R(2) = 0.2429, P = .007), but not with v(e). Multiple regression analysis showed K(trans) as the only independent correlate of both EnF(IAUC60>0) and EnF(IAUC60>2.5) for grade IV tumors.

Conclusions: This study suggests that in grade II tumors, EnF reflects v(p) and varies due to changes in vascular density. In grade IV gliomas, EnF is affected by K(trans) with secondary associated changes in v(p).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Algorithms
  • Brain Neoplasms / blood supply*
  • Brain Neoplasms / pathology
  • Brain Neoplasms / surgery
  • Computer Simulation
  • Contrast Media / administration & dosage
  • Diagnosis, Differential
  • Female
  • Gadolinium DTPA
  • Glioma / blood supply*
  • Glioma / pathology
  • Glioma / surgery
  • Humans
  • Image Enhancement / methods*
  • Image Processing, Computer-Assisted / methods*
  • Magnetic Resonance Angiography / methods*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Neovascularization, Pathologic / diagnosis*
  • Neovascularization, Pathologic / pathology
  • Neovascularization, Pathologic / surgery
  • Sensitivity and Specificity
  • Software
  • Statistics as Topic
  • Young Adult

Substances

  • Contrast Media
  • gadodiamide
  • Gadolinium DTPA