IntroductionKlippel-Trenaunay-Weber syndrome (KTWS) is a rare syndrome in which patients usually present with cutaneous hemangiomas, venous varicosities, and bone and soft tissue hypertrophy of the affected limb. Intracranial lesions in patients with KTWS are extremely rare, and are generally reported as single cases in the literature. We describe a rare case, where a patient with KTWS was found with a hemorrhagic grade IV astrocytoma. Although central nervous system abnormalities such as intracranial aneurysms and cerebral and spinal cord cavernomas have been described in patients with KTWS, to the best of our knowledge, this is the first report of an association between glioblastoma multiforme (grade IV astrocytoma) and KTWS in the English-language medical literature.Case presentationA 61-year-old white Caucasian man with a history of KTWS presented with seizures. Left upper and lower extremity hypertrophy, left foot, leg and ear gigantism and left-sided abdominal capillary hemangiomas were noted in the physical examination. Cranial computed tomography (CT) and magnetic resonance imaging (MRI) were obtained, showing a heterogeneous lesion in the cingulate gyrus, with peripheral and central areas of T1 hyperintensity and layering T2 hypointensity consistent with a hemorrhage. A right parasagittal frontal craniotomy was performed with an interhemispheric approach. We had difficulty controlling the bleeding with bipolar electrocautery during surgery and finally were able to stop the bleeding using surgicel and gelfoam. Postoperative cranial CT and MRI scans showed intraparenchymal hemorrhage centered within the medial right frontal lobe. There was no increase in hematoma size in consecutive CT scans.ConclusionsCo-occurrence of vascular abnormalities with KWTS should be taken into consideration to avoid perilous preoperative and postoperative complications.