Subacute methotrexate-related leukoencephalopathy with stroke-like presentation

Excerpt

A 20-year-old man was treated for B lymphoblastic leukemia and achieved complete remission after the first round of induction chemotherapy. Induction and the two subsequent consolidation therapy regimens were free of neurological adverse effects, although he received a total of five doses of intrathecal methotrexate (MTX). Anticancer agents (intravenous cytarabine, cyclophosphamide, pirarubicin hydrochloride, and oral mercaptopurine) were administrated with intrathecal MTX (12 mg), cytarabine (30 mg), and hydrocortisone (25 mg) on days 1 and 8 as a third consolidation chemotherapy. Eight days after the second intrathecal MTX injection, he developed sudden-onset right incomplete hemiplegia. Diffusion-weighted MRI (DWI) showed areas of high signal intensity in the white matter of the bilateral frontal lobes (Figure not shown) and the splenium of the corpus callosum (left column, Fig. 1). An apparent diffusion coefficient (ADC) map showed low signal intensity in the same lesion (middle column, Fig. 1). T1- and T2-weighted fast fluid-attenuated inversion recovery (FLAIR) (right column, Fig. 1) and magnetic resonance angiography images were unremarkable in all areas (Figure not shown). His symptoms resolved transiently the next morning; however, right complete hemiplegia, inability to vocalize, and dysphagia developed the same evening. His neurologic manifestations gradually improved within 2 days. A follow-up MRI on day+2 and day+4 after the onset of the stroke-like presentation showed new areas as well as partly reduced areas of high intensity in the white matter on DWI and of low intensity in the ADC map. FLAIR images showed a new area of high signal intensity on day+4. A follow-up MRI on day+18 demonstrated that the abnormal area had almost disappeared on DWI and the ADC map, and a residual lesion of high signal intensity was still observed on FLAIR images.

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