Abstract
Malignancy-associated stroke results from diverse cancer-related coagulopathies, and therapeutic options remain limited beyond management of the underlying malignancy. In particular, a large-vessel occlusion (LVO) that occurs despite multiple antithrombotic agents is difficult to attribute to routine atherothrombotic mechanisms and warrants consideration of occult malignancy. An 80-year-old man presented with left hemiparesis and dysarthria. Magnetic resonance imaging revealed an acute infarction in the right middle cerebral artery territory, and magnetic resonance angiography demonstrated right M1 occlusion. Mechanical thrombectomy using a combined technique achieved reperfusion. Whole-body computed tomography revealed splenomegaly, and rapidly progressive pancytopenia subsequently prompted bone marrow examination, confirming Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL). Hematuria with worsening anemia required discontinuation of antiplatelet therapy. Subsequently, recurrent occlusion of the M1 segment of the right middle cerebral artery occurred. Repeat thrombectomy achieved reperfusion, and a platelet-rich white thrombus was retrieved. Intracranial percutaneous transluminal angioplasty (PTA) was performed for residual stenosis, resulting in satisfactory luminal expansion. This case underscores the importance of suspecting malignancy-associated coagulopathy, rather than antithrombotic resistance, when LVO occurs despite multiple antithrombotic agents, and highlights the need for prompt systemic evaluation. Although this is a single case and additional cases need to accumulate, this case suggests that even when conventional antithrombotic therapy is not feasible due to malignancy-related bleeding risk, revascularization strategies may offer potential benefit in cancer-associated arterial thrombosis.