RESUMEN
We report a case of a 47-year-old male who had a left frontal lobe mass with specific magnetic resonance imaging (MRI). Four years previous to his admission to our hospital, he developed acute myelocytic leukemia and he was implanted with peripheral blood stem cell transplantation. One month before his admission, he was unable to walk due to right leg motor weakness. MRI revealed a round mass lesion at the left frontal lobe. Initial diagnosis was a brain abscess, so he was administered some antibacterial drug. However, his neurological symptoms kept getting worse with increase of mass size on MRI. T1-weighted MR images showed the mass as a low intensity lesion with incomplete ring-like Gd-enhancement. T2-weighted images showed the mass as a high intensity lesion with many linear shadows inside the mass. Diffusion weighted images showed the mass as a low intensity lesion. MR spectroscopy revealed an elevation of choline and lactate peak. Differential diagnosis was glioma or demyelinating disease. At the operation, the mass was light yellow and seen to be rich with vessels. The pathological diagnosis was xanthogranuloma in the brain. Postoperative course was uneventful. The frontal residual mass lesion decreased in size and Gd-enhancement.