Histology of Thrombectomy Specimen Reveals Cardiac Tumor Embolus in Cryptogenic Young Stroke

Clot Composition Analysis as a Diagnostic Tool to Gain Insight into Ischemic Stroke Etiology: A Systematic Review

Mechanical thrombectomy renders the occluding clot available for analysis. Insights into thrombus composition could help establish the stroke cause. We aimed to investigate the value of clot composition analysis as a complementary diagnostic tool in determining the etiology of large vessel occlusion (LVO) ischemic strokes (International Prospective Register of Systematic Reviews [PROSPERO] registration # CRD42020199436). Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we ran searches on Medline (using the PubMed interface) and Web of Science for studies reporting analyses of thrombi retrieved from LVO stroke patients subjected to mechanical thrombectomy (January 1, 2006 to September 21, 2020). The PubMed search was updated weekly up to February 22, 2021. Reference lists of included studies and relevant reviews were hand-searched. From 1,714 identified studies, 134 eligible studies (97 cohort studies, 31 case reports, and six case series) were included in the qualitative synthesis. Physical, histopathological, biological, and microbiological analyses provided information about the gross appearance, mechanical properties, structure, and composition of the thrombi. There were non-unanimous associations of thrombus size, structure, and composition (mainly proportions of fibrin and blood formed elements) with the Trial of Org 10172 in Acute Stroke Treatment (TOAST) etiology and underlying pathologies, and similarities between cryptogenic thrombi and those of known TOAST etiology. Individual thrombus analysis contributed to the diagnosis, mainly in atypical cases. Although cohort studies report an abundance of quantitative rates of main thrombus components, a definite clot signature for accurate diagnosis of stroke etiology is still lacking. Nevertheless, the qualitative examination of the embolus remains an invaluable tool for diagnosing individual cases, particularly regarding atypical stroke causes.

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.

Successful endovascular removal of a chondroblastic osteosarcoma embolus within the left middle cerebral artery

A 57-year-old woman with metastatic chondroblastic osteosarcoma developed sudden-onset right-sided weakness and aphasia. She was found to have an occluded left middle cerebral artery (M1 segment) and underwent endovascular stroke intervention with return to a normal neurological exam within 24 h. Histologic analysis of the embolus was consistent with chondroblastic osteosarcoma.

Syncope in a female patient. Echocardiography and cardiac computed tomography reveal an unexpected diagnosis

Papillary fibroelastoma is a benign cardiac tumor with a high potential of embolization. Coronary computed tomography is a valuable tool for the work-up of patients with papillary fibroelastoma, providing accurate information regarding the coronary circulation and morphology of the cardiac mass.