Evaluation of the late effects of CNS prophylactic treatment in childhood acute lymphoblastic leukemia (ALL) using magnetic resonance spectroscopy

Abstract

Purpose: The aim of the study was to evaluate the late changes seen in Magnetic Resonance Spectroscopy (MRS) of the brain in Acute Lymphoblastic Leukemia (ALL) survivors to assess neurotoxicity following prophylactic treatment with cranial irradiation (CRT) and/or intrathecal (ITMTX) and systemic MTX. Materials and Methods: The study was performed on two groups of patients. The first group consisted of 30 children who received CRT and ITMTX, and the second group was comprised of 15 children treated only with ITMTX. All patients were ALL survivors treated between 1994 and 2002. Radiotherapy was performed using two opposite fields for a total dose of 18 Gy. The children were examined from 6 to 12 years after treatment. All children underwent a physical and neurological examination and MRI/MRS studies. 1H-MR spectra were acquired from frontal and occipital regions of the brain. Mean values and standard deviations were calculated for following metabolite ratios: NAA/Cr, Cho/Cr, Cho/NAA, and mI/Cr. Results: Three of the 45 children (11%) presented with white matter changes upon MRI examination. All children with MRI abnormalities received CRT. In 13 (31%) children, changes in 1H-MRS metabolite ratios were seen. We observed decreased NAA/Cr and Cho/Cr ratios. MR spectroscopy showed a significant reduction (P