A rare spinal cord infarction caused by aortic mural thrombosis in a patient with cancer and the associated diagnostic challenges due to it mimicking spinal cord compression: A case report.

Patients with malignancy are at an increased risk of arterial thrombosis; however, spinal cord infarction (SCI) secondary to aortic mural thrombosis is rare. The present report describes a case of SCI in a 75-year-old man with cancer of unknown primary undergoing chemotherapy and immune checkpoint inhibitor (ICI) therapy. The patient presented with acute bilateral lower limb weakness and bladder-rectal dysfunction. Although spinal cord compression was initially suspected due to multiple vertebral metastases, contrast-enhanced magnetic resonance imaging revealed no evidence of compression or leptomeningeal dissemination. Diffusion-weighted imaging demonstrated hyperintensity with reduced apparent diffusion coefficient values in the spinal cord, consistent with SCI. Immune-related adverse event-associated myelitis was excluded based on cerebrospinal fluid analysis. Contrast-enhanced computed tomography revealed a large aortic mural thrombus, which was considered the most likely etiology of SCI after exclusion of alternative causes. Anticoagulation therapy combined with early rehabilitation led to partial neurological recovery. This case underscores the importance of considering SCI in the differential diagnosis of acute neurological deficits in patients with malignancy receiving ICI therapy.