Pathological confirmation of 4 cases with isolated cortical vein thrombosis previously misdiagnosed as brain tumor.

Isolated cortical vein thrombosis (ICoVT) is a rare form of cerebral venous thrombosis and is easily misdiagnosed as brain tumor due to its atypical clinical presentations and radiological findings similar to brain tumors. The present study focused on 4 patients with ICoVT, 2 men and 2 women. In the 2 male patients, the onset of disease was insidious, with progressive numbness and weakness in limbs as the major symptoms. By contrast, 2 female patients suffered from acute onset of symptoms, presenting with headache and seizures. Brain computed tomography and magnetic resonance imaging showed large hemorrhagic lesions surrounded by massive edemas in the 4 patients. Brain biopsies were performed in the 4 patients due to concern for brain tumors. However, the pathological results supported the diagnosis of ICoVT, and the subsequent anticoagulant treatment administered was effective for all 4 patients. In conclusion, ICoVT can be easily misdiagnosed as brain tumor because of the atypical clinical and imaging features. The results suggested that the possibility of ICoVT always be considered in patients with neuroimaging showing cortical hemorrhagic lesions with massive edemas.