Mechanical Thrombectomy for Acute Middle Cerebral Artery Occlusion Caused by Tumor Embolism: A Case Report

OBJECTIVE: We report a case of acute middle cerebral artery (MCA) occlusion caused by tumor embolism. CASE PRESENTATION: A 64-year-old man with lung cancer presented with sudden onset left-sided hemiparesis and sensory disturbance. Diffusion-weighted imaging (DWI) revealed hyper-intense foci in the right MCA territory and magnetic resonance angiography (MRA) demonstrated right MCA M2 segment occlusion. Mechanical thrombectomy (MT) was performed with Thrombolysis in Cerebral Infarction 2B recanalization. On histopathology, thrombus composed of fibrin and squamous cell carcinoma was observed. We diagnosed him with tumor embolism from lung cancer that invaded the pulmonary vein and the left atrium. CONCLUSION: Tumor cells may be confirmed by pathological examination regardless of the morphology of the embolus. Pathological examination of the cerebral embolus is useful for the accurate diagnosis of ischemic stroke subtypes.