Introduction
Ischaemic stroke (IS) and cancer represent the two leading causes of mortality among the elderly population.1 IS can manifest either subsequent to or prior to a cancer diagnosis.2 Multicentre studies conducted in Europe have revealed that the prevalence of underlying cancer disease in IS patients is higher compared with the general population.3 4
Several potential causes of cancer-associated stroke have been proposed, encompassing both direct and indirect mechanisms. These include compression, embolism or invasion of blood vessels; cancer-induced activation of the coagulation cascade; hyperactivity of fibrinolysis-system; and treatment-related side effects.5 Prior investigations have elucidated several factors independently linked with active cancer in IS patients. These include undetermined aetiology stroke, inflammatory markers, hypercoagulability indicators.6 7
Enlarged perivascular spaces (EPVS) are fluid-filled cavities around small brain vessels seen on MRI. EPVS may manifest in association with a range of pathological conditions like cerebral small vessel disease, abnormal protein accumulation, blood–brain barrier (BBB) leakage or neuroinflammation.8–11 Cancer has the potential to induce systemic inflammatory responses, thereby impacting the central nervous system and resulting in neuroinflammation.12 The systemic inflammatory markers may serve as an indicator to identify the risk for EPVS, especially for basal ganglion EPVS (BG-EPVS).13 The disruption of BBB and inflammation associated with BG-EPVS may also in turn create a more favourable environment for the occurrence of stroke in individuals with cancer.14 15 Research on the link between BG-EPVS and cancer-associated strokes is necessary to elucidate the underlying mechanisms involved.
Numerous studies have highlighted the role of cancer treatment side effects as potential mechanisms for cancer-associated stroke.16 Structural changes in the brain resulting from cancer and its treatment, such as reductions in global and local grey matter volumes, compromised white matter microstructural integrity and alterations in brain networks, have been extensively documented in the literature.17 Additionally, prior research has suggested a potential link between radiation therapy and the development of EPVS.18 19 Consequently, there is a need for further investigation into the inconsistent role of BG-EPVS in cancer-associated stroke among individuals who have undergone cancer treatment.
For patients and doctors in the field of neurology, it is of great significance to identify cancer-associated stroke early. Given the potential involvement of BG-EPVS in the pathogenesis of cancer-associated stroke, this study aims to conduct a case–control analysis to assess the levels of BG-EPVS and to investigate its diagnostic value in the context of cancer-associated stroke. We hypothesise that the cancer group will have higher levels of BG-EPVS compared with the control group. And considering the potential impact of cancer treatment, we also hypothesise that the role of BG-EPVS in the diagnosis of cancer-associated stroke may vary depending on whether cancer treatment has been administered.