Magnetic resonance imaging in childhood leukemia survivors treated with cranial radiotherapy: A cross sectional, single center study

Background: Children treated with cranial radiotherapy (CRT) for leukemia are at risk of developing central nervous system injuries. Magnetic resonance imaging (MRI) represents the examination method of choice for evaluating radiation-induced brain complications. The purpose of this report is to describe the spectrum of MRI abnormalities detected in a group of survivors of leukemia treated with cranial irradiation. Procedures: In this cross-sectional, single center study, 56 patients (median age at follow-up 19 years) receiving CRT as cranial prophylaxis (CP) included in the leukemia protocol (total dose 1,800-2,400cGy) and/or in the total body irradiation regimen (990-1,200cGy) before hematopoietic stem cell transplant, were evaluated by MRI after a median interval of 11 years (range 2-27) following CRT. Results: Fifty-nine MRI abnormalities (32 cavernomas, nine focal areas of gliosis, seven dystrophic mineralizations, five cerebral atrophies, four pituitary atrophies, one diffuse radiation leukoencephalopathy, and one meningioma) were found in 43 patients. The longest interval between CRT and MRI and oldest age at follow-up represented the two risk factors that were statistically associated with MRI lesions (P=0.032 and 0.033, respectively). Cerebral cavernomas (CC) were the most frequent MRI abnormalities (57%). All patients with CC were asymptomatic at diagnosis and during follow-up, except one who had aspecific neurological manifestations and micro hemorrhages. Conclusions: These results confirm that total doses and modalities of fractionation dose of CRT were not significantly associated with MRI abnormalities. Moreover, in our experience none of the patients developed neurological symptoms related to MRI abnormalities, and furthermore, the CC remained substantially stable during follow-up.