ISCHEMIC STROKE / CLASSIFICATION AND ETIOPATHOGENESIS

Created 15/11/2021, last revision 26/12/2022

• cancer patients are at increased risk of not only venous but also arterial thromboembolism (ATE),  including stroke and MI) [Mulder, 2021] [Babak, 2015]
  • stroke is, however, not the most common complication of cancer–associated thrombosis;  HR for stroke is approx.  1.44   [Paterson, 2022]
    
  • the highest risk of stroke is with pancreatic, lung, and colorectal tumors
• some strokes are directly related to the tumor or metastases, others to diagnostic methods or therapy (early and delayed cardiovascular complications)
• in cryptogenic stroke, cancer survey is suggested ⇒ thromboembolism may be the first manifestation of the disease
  • tremendously increased D-dimers have been found in patients with cryptogenic stroke and occult cancer

Etiopathogenesis

The cause of a cancer-related stroke is usually complex; multiple mechanisms may contribute:

• secondary paraneoplastic syndromes
  • nonbacterial endocarditis and hypercoagulable state are common causes
  • vasculitides are rare – only ~5% of vasculitides are paraneoplastic in origin, and only a small percentage of these lead to ischemia [Sánches-Guerrero, 1990]
• early or delayed complications of therapy   (Anand, 2016)
  • cardiomyopathies (anthracyclines or trastuzumab)
  • systemic hypertension
  • myocardial ischemia
  • pulmonary hypertension
  • radiation-induced vasculopathy
  • chemotherapy-induced vasculopathy

Clinical presentation

• similar proportions of ischemic stroke and bleeding, cerebral sinus thrombosis occurs less frequently
  • hemorrhages are frequent in leukemias
  • ischemic strokes typically occur in carcinomas and lymphomas
• focal neurological deficit corresponds to the affected vascular territory
  
• frequent signs of progressive encephalopathy, caused by:
  • multiple embolizations in marantic endocarditis
  • hypercoagulable state with multiple infarcts
  • vasculitis
  • differentiate encephalopathy related to paraneoplastic syndrome (limbic encephalitis, etc.) or therapy-induced encephalopathies
    

Diagnostic evaluation

• standard imaging methods (CT+CTA / MR+MRA, neurosonology)
  • often multiple lesions (even in hemorrhages)
  • in DDx distinguish tumorous infiltration from ischemia    
• blood tests
  • complete blood count (CBC) + coagulation tests + erythrocyte sedimentation rate (ESR)
    
  • basic metabolic panel
  • in suspected vasculitis, perform CSF examination
    
• look for other vascular manifestations of the tumor (venous thrombosis in legs, venous thrombosis in atypical localisations, migrating thrombophlebitis, etc.)

Management