Endovascular treatment in patients with acute ischemic stroke and cancer: Systematic review and meta-analysis

Acute ischaemic stroke in active cancer versus non-cancer patients: stroke characteristics, mechanisms and clinical outcomes

BACKGROUND AND PURPOSE

Demographics, clinical characteristics, stroke mechanisms and long-term outcomes were compared between acute ischaemic stroke (AIS) patients with active cancer (AC) versus non-cancer patients.

METHODS

Using data from 2003 to 2021 in the Acute STroke Registry and Analysis of Lausanne, a retrospective cohort study was performed comparing patients with AC, including previously known and newly diagnosed cancers, with non-cancer patients. Patients with inactive cancer were excluded. Outcomes were the modified Rankin Scale (mRS) score at 3 months, death and cerebrovascular recurrences at 12 months before and after propensity score matching.

RESULTS

Amongst 6686 patients with AIS, 1065 (15.9%) had a history of cancer. After excluding 700 (10.4%) patients with inactive cancer, there were 365 (5.5%) patients with AC and 5621 (84%) non-cancer AIS patients. Amongst AC patients, 154 (42.2%) strokes were classified as cancer related. In multivariable analysis, patients with AC were older (adjusted odds ratio [aOR] 1.02, 95% confidence interval [CI] 1.00-1.03), had fewer vascular risk factors and were 48% less likely to receive reperfusion therapies (aOR 0.52, 95% CI 0.35-0.76). Three-month mRS scores were not different in AC patients (aOR 2.18, 95% CI 0.96-5.00). At 12 months, death (adjusted hazard ratio 1.91, 95% CI 1.50-2.43) and risk of cerebrovascular recurrence (sub-distribution hazard ratio 1.68, 95% CI 1.22-2.31) before and after propensity score matching were higher in AC patients.

CONCLUSIONS

In a large institutional registry spanning nearly two decades, AIS patients with AC had less past cerebrovascular disease but a higher 1-year risk of subsequent death and cerebrovascular recurrence compared to non-cancer patients. Antithrombotic medications at discharge may reduce this risk in AC patients.

Ischemic Stroke in Cancer: Mechanisms, Biomarkers, and Implications for Treatment

Ischemic stroke is an important cause of morbidity and mortality in cancer patients. The underlying mechanisms linking cancer and stroke are not completely understood. Long-standing and more recent evidence suggests that cancer-associated prothrombotic states, along with treatment-related vascular toxicity, such as with chemotherapy and immunotherapy, contribute to an increased risk of ischemic stroke in cancer patients. Novel biomarkers, including coagulation, platelet and endothelial markers, cell-free DNA, and extracellular vesicles are being investigated for their potential to improve risk stratification and patient selection for clinical trials and to help guide personalized antithrombotic strategies. Treatment of cancer-related stroke poses unique challenges, including the need to balance the risk of recurrent stroke and other thromboembolic events with that of bleeding associated with antithrombotic therapy. In addition, how and when to restart cancer treatment after stroke remains unclear. In this review, we summarize current knowledge on the mechanisms underlying ischemic stroke in cancer, propose an etiological classification system unique to cancer-related stroke to help guide patient characterization, provide an overview of promising biomarkers and their clinical utility, and discuss the current state of evidence-based management strategies for cancer-related stroke. Ultimately, a personalized approach to stroke prevention and treatment is required in cancer patients, considering both the underlying cancer biology and the individual patient's risk profile.

Long-term outcomes of mechanical thrombectomy in acute ischaemic stroke patients with concomitant malignancy

Introduction

Patients with cancer (CP) need a different approach to acute ischaemic stroke (AIS) treatment as intravenous thrombolysis (IVT) may be contraindicated. Mechanical thrombectomy (MT) is a treatment of choice for otherwise eligible patients, although the literature on its long-term outcomes in CP is limited.

Aim

Assessing outcomes of MT-treated AIS patients with concomitant malignancy in a year-long follow-up.

Material and methods

The study included 593 MT-treated AIS patients admitted in 2019-2021. The group was divided into CP (defined as a diagnosis of malignancy and undergoing/qualified for cancer treatment within previous 5 years) and a control group. The profile of cardiovascular risk factors, stroke severity and discharge, 90-day and 365-day outcomes were compared between the groups.

Results

CP and controls had a similar profile of cardiovascular risk factors and comparable stroke severity. CP were less frequently treated with IVT (25.7% vs. 59.1%, p < 0.001). There were no differences between the groups in the successful reperfusion rate and occurrence of haemorrhagic complications. Discharge and 90-day outcomes were similar. CP had higher 365-day mortality (48.6% vs. 29.9%, p = 0.024) but the percentage of patients achieving good functional outcome in a year-long observation was comparable.

Conclusions

Treatment with MT seems beneficial for AIS patients with concomitant malignancy both in short- and long-term observation.

Cancer-Associated Stroke and Acute Endovascular Reperfusion Therapy

Since stroke is often associated with cancer, acute stroke patients with cancer undergoing endovascular therapy (EVT) are not uncommon. Reportedly, the proportion of such cases is approximately 6%-7% of all stroke EVT cases. Ischemic stroke in patients with active cancer (cancer-associated stroke) includes not only strokes caused by cancer-related hypercoagulability but also coincident strokes due to common etiologies, strokes associated with tumor emboli, direct tumor invasion of blood vessels, and strokes associated with cancer therapy. Stroke caused by cancer-related hypercoagulability itself encompasses various entities, including paradoxical embolism, stroke due to nonbacterial thrombotic endocarditis, and in situ arterial occlusion due to disseminated intravascular coagulation or thrombotic microangiopathy. Thus, diverse mechanisms contribute to cancer-associated stroke, emphasizing the need to consider individualized treatment strategies for acute cases involving large vessel occlusion. Observational studies have shown that EVT for cancer-associated stroke results in poorer clinical outcomes, but with comparable rates of successful reperfusion and symptomatic intracranial hemorrhage when compared with stroke patients without cancer. This suggests that denying patients EVT solely on the basis of comorbid active cancer is inappropriate, and decision-making should be shared with the patients and their families, preferably through a multidisciplinary team approach. Thrombi retrieved from patients with stroke caused by cancer-related hypercoagulability have unique characteristics, being predominantly platelet rich and difficult to retrieve. Preprocedural imaging and serum biomarkers, including the hyperdense vessel sign on non-contrast CT, susceptibility vessel sign on T2* or susceptibility-weighted MRI, three-territory sign on MRI, and D-dimer levels, are valuable in evaluating the stroke subtype and thrombus features. Thrombectomy techniques, such as contact aspiration and stent retriever monotherapy, have shown varying degrees of effectiveness for stroke caused by cancer-related hypercoagulability, warranting further study. After reperfusion therapy, appropriate treatment for the prevention of stroke recurrence should be initiated, considering the specific stroke subtypes. In conclusion, cancer-associated stroke encompasses diverse subtypes, and thrombi associated with stroke caused by cancer-related hypercoagulability present various challenges for thrombectomy. Individualized treatment approaches based on underlying mechanisms are essential for improving outcomes in acute stroke patients with active cancer. Optimization of preprocedural diagnosis, EVT techniques, and secondary prevention of stroke caused by cancer-related hypercoagulability will lead to better management of these patients and enhance their quality of life.

Endovascular therapy for acute ischemic stroke in patients with active malignancy: a meta-analysis with trial sequential analysis

BACKGROUND

Active malignancy has a poorer prognosis and more deaths in patients with acute ischemic stroke (AIS). The outcomes of endovascular therapy (EVT) remain controversial in patients with AIS and active malignancy.

METHODS

We searched PubMed, Cochrane, and Embase for articles published up to June 1, 2022. The primary outcome was good functional outcome at 3 months and successful reperfusion between patients with cancer and AIS and control patients. The secondary and safety outcomes included mortality at 3 months, in-hospital mortality, symptomatic intracerebral hemorrhage (sICH), any ICH, and subarachnoid hemorrhage (SAH).

RESULTS

Twelve studies involving 5944 patients with AIS secondary to EVT were included (389 patients having active malignancy). The OR of good functional outcome at 3 months was 0.53 (95% CI 0.41 to 0.67) between the two groups. The OR of successful reperfusion between the two groups was 0.90 (95% CI 0.63 to 1.30). Compared with patients without cancers, those with cancers had a higher risk of mortality at 3 months (OR 3.64; 95% CI 2.35 to 6.27) and in-hospital mortality (OR 3.46; 95% CI 1.71 to 7.01). Despite a higher point estimate regarding any ICH (OR 1.41; 95% CI 1.01 to 1.96) and SAH (OR 2.53; 95% CI 1.10 to 5.81), sICH (OR 0.85; 95% CI 0.51 to 1.42) was not significant.

CONCLUSION

Although a quarter of patients with active malignancy and AIS regained functional independence, physicians and patients should consider whether to apply EVT in patients with active malignancy.

Acute reperfusion treatment and secondary prevention of cancer-related stroke: comprehensive overview and proposal of clinical algorithm

Cancer-related stroke (CRS), referring to ischemic stroke occurring in cancer patients without other clear etiology, represents a clinical challenge, as it is associated with unfavorable clinical outcomes including high rates of recurrence and mortality. There are scarce international recommendations and limited consensus statements on CRS management. For this comprehensive overview, the available studies/reviews/meta-analyses on the use of acute reperfusion and secondary prevention treatments for cancer patients with ischemic stroke, focusing on antithrombotic agents, were collected and summarized. A practical management algorithm was designed per the available data. In short, acute reperfusion in the form of intravenous thrombolysis and mechanical thrombectomy appears to be safe in CRS and can be considered for eligible patients, though the functional outcomes are often poor, and mostly defined by the preexisting condition. Many patients carry indications for anticoagulation, in which case vitamin K antagonists are not preferred, while low-molecular weight heparins remain the treatment of choice; direct oral anticoagulants can be alternatively considered but are contraindicated for gastrointestinal malignancies. For patients without clear anticoagulation indications, no net benefit for anticoagulation compared to aspirin has been shown. Other targeted treatment options should be evaluated in an individualized approach, alongside the appropriate management of conventional cerebrovascular risk factors. Oncological treatment should be swiftly initiated/continued. In conclusion, acute CRS remains a clinical challenge, with many patients suffering recurrent stroke, despite preventive measures. More randomized-controlled clinical trials are urgently needed to pinpoint the most effective management options for this subset of stroke patients.

Clinical and Demographic Characteristics, Mechanisms, and Outcomes in Patients With Acute Ischemic Stroke and Newly Diagnosed or Known Active Cancer

BACKGROUND AND OBJECTIVES

Patients with a new diagnosis of cancer carry an increased risk of acute ischemic stroke (AIS), and this risk varies depending on age, cancer type, stage, and time from diagnosis. Whether patients with AIS with a new diagnosis of neoplasm represent a distinct subset from those with a previously known active malignancy remains unclear. We aimed to estimate the rate of stroke in patients with newly diagnosed cancer (NC) and previously known active cancer (KC) and to compare the demographic and clinical features, stroke mechanisms, and long-term outcomes between groups.

METHODS

Using 2003-2021 data from the Acute STroke Registry and Analysis of Lausanne registry, we compared patients with KC with patients with NC (cancer identified during AIS hospitalization or within the following 12 months). Patients with inactive and no history of cancer were excluded. Outcomes were the modified Rankin scale (mRS) score at 3 months and mortality and recurrent stroke at 12 months. We used multivariable regression analyses to compare outcomes between groups while adjusting for important prognostic variables.

RESULTS

Among 6,686 patients with AIS, 362 (5.4%) had active cancer (AC), including 102 (1.5%) with NC. Gastrointestinal and genitourinary cancers were the most frequent cancer types. Among all patients with AC, 152 (42.5%) AISs were classified as cancer related, with nearly half of these cases attributed to hypercoagulability. In multivariable analysis, patients with NC had less prestroke disability (adjusted odds ratio [aOR] 0.62, 95% CI 0.44-0.86) and fewer prior stroke/transient ischemic attack events (aOR 0.43, 95% CI 0.21-0.88) than patients with KC. Three-month mRS scores were similar between cancer groups (aOR 1.27, 95% CI 0.65-2.49) and were predominantly driven by the presence of newly diagnosed brain metastases (aOR 7.22, 95% CI 1.49-43.17) and metastatic cancer (aOR 2.19, 95% CI 1.22-3.97). At 12 months, mortality risk was higher in patients with NC vs patients with KC (hazard ratio [HR] 2.11, 95% CI 1.38-3.21), while recurrent stroke risk was similar between groups (adjusted HR 1.27, 95% CI 0.67-2.43).

DISCUSSION

In a comprehensive institutional registry spanning nearly 2 decades, 5.4% of patients with AIS had AC, a quarter of which were diagnosed during or within 12 months after the index stroke hospitalization. Patients with NC had less disability and prior cerebrovascular disease, but a higher 1-year risk of subsequent death than patients with KC.

Stroke and cancer

Association between stroke and cancer is well-established and has led to a growing literature over the past decades. Risk of ischemic and hemorrhagic stroke is increased among patients with newly diagnosed cancer and 5-10% of stroke patients bear an active cancer. All cancers are concerned, but hematological malignancy in childhood and adenocarcinoma from lung, digestive tract and pancreas in adults are most usually identified. Unique stroke mechanisms are dominated by hypercoagulation, a condition that may lead to both arterial and venous cerebral thromboembolism. Direct tumor effects, infections and therapies may also play some active role in stroke happening. Magnetic Resonance Imaging (MRI) is helpful in: i) detecting typical patterns of ischemic stroke in cancer patients (i.e. concomitant strokes in multiple arterial territories); ii) distinguishing spontaneous intracerebral hemorrhage from tumor bleeding. Recent literature suggests that acute treatment using intravenous thrombolysis is safe in non-metastatic cancer patients. First results from endovascular procedures are reassuring, although arterial reobstruction is more frequent than in cancer-free patients. Prognosis is worse in patients with compared to those without cancer and mostly depends upon several predictors such as the initial stroke severity and the presence of metastasis. In the present review, we aim to provide some practical responses to neurologists about the stroke-cancer association, including prevalence, stroke mechanisms, biomarkers indicative for an occult cancer, influence of neoplasia on acute and long-term stroke treatments, and prognosis.