Dissociation between 11C-methionine-PET and Gd-MRI in the longitudinal features of Glioblastoma after postoperative radiotherapy.

Dissociation between 11C-methionine-PET and Gd-MRI in the longitudinal features of Glioblastoma after postoperative radiotherapy.

World Neurosurg. 2019 Feb 01;:

Authors: Kawasaki T, Miwa K, Shinoda J, Asano Y, Takei H, Ikegame Y, Yokoyama K, Yano H, Iwama T

Abstract
INTRODUCTION: The aims of this study are to compare the longitudinal radiological changes of Glioblastoma multiforme (GBM) after radiotherapy (RT) between 11C-methionine positron emission tomographic (MET-PET) imaging and gadolinium enhanced MRI (Gd-MRI), and to clarify whether these changes predict patient survival.
METHODS: This study included 30 patients with newly diagnosed GBM, who received MET-PET and Gd-MRI postoperatively before and every three months after RT (30, 28, and 16 patients were followed for 3, 6, and 9 months after RT, respectively). Regardless of the size after surgery, there remained tumor lesions radiologically in all cases on MET-PET and Gd-MRI. The changes of the lesion/normal brain uptake ratio on MET-PET (L/N ratio) and the contrast enhancing lesion volume on Gd-MRI (Gd-vol) were examined.
RESULTS: The L/N ratio was decreased until 9 months after RT with significance until 3 months. The Gd-vol was decreased until 3 months and thereafter increased significantly until 9 months. The variation rates (VRs) of the L/N ratio between pre- and 3 months post-RT significantly differentiated patients with survival more than 23 months from those with survival of 23 months or less. The best cut-off value of the VR was -0.366, while providing a specificity of 94.7% and a sensitivity of 60.0%. The median survivals were 39.5 and 17.0 months in patients with a VR of -0.366 or less and those with a VR of more than -0.366.
CONCLUSIONS: There could be a significant dissociation in the longitudinal changes of GBM after RT between MET-PET and Gd-MRI. The VR of the L/N ratio between pre- and 3 months post-RT, was suggested to be related significantly to patient survival.

PMID: 30716494 [PubMed - as supplied by publisher]

from A via a.sfakia on Inoreader http://bit.ly/2RFNuo8