LAUSR

HIGHLIGHTSCapecitabine can induce a severe toxic leukoencephalopathy in rare cases.MRI is very evocative, showing bilateral diffusion‐restricted deep white matter lesions.Lesions involve centrum ovale, corpus callosum and pyramidal tracts.Symptoms may regress completely once the drug administration is discontinued. ABSTRACT A 45‐year‐old woman was treated by Capecitabine (Xeloda®) during 6 days for breast cancer with metastatic bone lesions when she presented with nausea, headaches, muscle cramps, dysarthria and swallowing disorders. A stroke was first suspected. Brain CT was normal. MRI showed bilateral and symmetric high signal intensities of deep white matter, corpus callosum and corticospinal tracts on diffusion‐weighted imaging and T2 fluid‐attenuated inversion recovery (FLAIR) sequence, similar to 5‐FU acute leukoencephalopathy. An acute toxic leukoencephalopathy was diagnosed prompting to discontinue capecitabine, which allowed a regression of the symptoms. Though acute toxic leukoencephalopathies with pseudo‐stroke presentation have been reported with other chemotherapy agents such as methotrexate or 5‐fluorouracil (5‐FU), cases of leukoencephalopathy induced by capecitabine are less reported and less well known. This oral precursor of 5‐FU is commonly used to treat colorectal, stomach or breast cancers. Neurotoxicity of other 5‐FU derivates like cormafur and tergafur have rarely been depicted as well. Although 5‐FU‐induced leukoencephalopathy is known, the potential toxicity of its precursor should be acknowledged as well. Early detection of chemotherapy‐induced toxicity by MRI is crucial as symptoms may be reversible to the condition that chemotherapy is immediately discontinued.