1H Magnetic Resonance Spectroscopy assessment of the radiochemotherapy response in Gliomatosis Cerebri

摘要

This study was designed to perform 1H Magnetic Resonance Spectroscopy (MRS) on a Gliomatosis Cerebri (GC) patient who received radiochemotherapy, in order to assess brain metabolic changes that result from treatment. One patient with GC was studied after her informed consent was obtained. She was treated with whole brain radiation therapy receiving a total dose of 55 Gy in 30 fractions over 60 days. After radiotherapy, she received Temozolomide 100 mgs for 5 days each 28 days. MRI and MRS were performed at the beginning of treatment and after 3, 12 and 24 months of therapy on a 1.5 T scanner. Chemical-Shift Imaging (CSI) was concluded using 1500/30/6 (TR/TE/Acquisitions). Metabolic signals from Lipids (Lip), Lactate (Lac), N-Acetylaspartate (NAA), Creatine (Cr), Choline (Cho), and myo-Inositol (mI) were detected and NAA/Cr, Cho/Cr, mI/Cr and NAA/Cho ratios were calculated. The GC diagnosis was confirmed by a stereotactic biopsy of the area where the Cho/Cr ratio reached the highest value. A decrease in the mI/Cr ratio was found in association with tumor mass reduction after radiochemotherapy. NAA/Cr ratio was increased after radiotherapy as well. Based on those results we conclude that MRS may provide a useful tool for monitoring the therapeutic response in GC when brain radiation and chemotherapy is applied. The link between the decrease of mI/Cr ratio and the partial response of the tumor may provide a fertile ground for developing better forms of therapy and predicting its efficacy to improve GC patients′ survival.