Necrosis in Tumour Bed-is this Radiation Necrosis or Tumour Necrosis: Role of Dynamic Contrast Enhanced Perfusion MRI? First Step- Clinical Feasibility Study

Purpose of Study: To assess adequacy of relative cerebral blood volume (rCBV) and permeability index in differentiating radiation necrosis and tumour necrosis.

Materials and Methods: In this study we analyzed relative cerebral blood volume rCBV and permeability index from the enhancing areas to the contralateral white matter in 10 post treatment malignant brain lesions. The lesions were compatible with features of MR-morphological tumor progression. The diagnosis (real progression vs. radiation necrosis) was determined by histopathology or by clinical/MRI-follow-up.

Results: There were significant differences between tumor progression (N = 5) and radiation necrosis (N = 4) and mixed (N=1). An increased rCBV and permeability index are highly predictive of tumour progression.

Conclusion: Initial results of CBV and permeability map in differentiating tumor necrosis and tumor growth were highly promising.