Quantitative short echo time ¹H MRSI of the peripheral edematous region of human brain tumors in the differentiation between glioblastoma, metastasis, and meningioma

Abstract

Purpose:To assess metabolite levels in peritumoral edematous (PO) and surrounding apparently normal (SAN) brain regions of glioblastoma, metastasis, and meningioma in humans with 1H‐MRSI to find biomarkers that can discriminate between tumors and characterize infiltrative tumor growth.Materials and Methods:Magnetic resonance (MR) spectra (semi‐LASER MRSI, 30 msec echo time, 3T) were selected from regions of interest (ROIs) under MRI guidance, and after quality control of MR spectra. Statistical testing between patient groups was performed for mean metabolite ratios of an entire ROI and for the highest value within that ROI.Results:The highest ratios of the level of choline compounds and the sum of myo‐inositol and glycine over N‐acetylaspartate and creatine compounds were significantly increased in PO regions of glioblastoma versus that of metastasis and meningioma. In the SAN region of glioblastoma some of these ratios were increased. Differences were less prominent for metabolite levels averaged over entire ROIs.Conclusion:Specific metabolite ratios in PO and SAN regions can be used to discriminate glioblastoma from metastasis and meningioma. An analysis of these ratios averaged over entire ROIs and those with most abnormal values indicates that infiltrative tumor growth in glioblastoma is inhomogeneous and extends into the SAN region. J. Magn. Reson. Imaging 2012;36:1072–1082. © 2012 Wiley Periodicals, Inc.

In Vivo 31P magnetic resonance spectroscopic imaging (MRSI) for metabolic profiling of human breast cancer xenografts

“…Noninvasive metabolic profiling by 3D 31 P MRSI can discriminate between subtypes of breast cancer based on different concentrations of choline-and ethanolamine-containing phospholipids.…”

“…Metabolic profiles from luminal-like and basal-like xenograft tumors were obtained in vivo using 3D 31 P MRSI at 11.7T and from tissue extracts in vitro at 14.1T. Gene expression analysis was performed in order to support metabolic differences between the two xenografts.…”

“…Results: In vivo 31 P MR spectra were obtained in which the prominent resonances from phospholipid metabolites were detected at a high signal-to-noise ratio (SNR >7.5). Metabolic profiles obtained in vivo were in agreement with those obtained in vitro and could be used to discriminate between the two xenograft models, based on the levels of phosphocholine, phosphoethanolamine, glycerophosphocholine, and glycerophosphoethanolamine.…”

“…The individual evaluation of each of these compounds might greatly aid differential tumor diagnosis and help to monitor the response of targeted anticancer therapies (10). 31 Phosphorus ( 31 P) MRS can detect phospholipid signals such as of GPC and PC and also of phosphoethanolamine (PEtn) and glycerophosphoethanolamine (GPE). In vivo 31 P MRS studies showed that malignant transformation is associated with elevated phosphomonoester (PME) levels (dominated by PCho and PEtn signals) and phosphodiesters (PDE) levels (dominated by GPC and GPE) (11).…”

“…We explored 3D 31 P magnetic resonance spectroscopic imaging (MRSI) at high magnetic field for in vivo assessment of individual phospholipids in two patient-derived breast cancer xenografts representing good and poor prognosis (luminal-and basal-like tumors).…”