Research Report: Mechanical Thrombectomy Outcomes in Acute Ischemic Stroke Patients with Cancer

Background

Acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) is a severe neurological injury, which is further complicated in cancer patients. Cancer-related stroke mechanisms include a hypercoagulable state, coagulopathies due to tumor-secreted factors or microparticles, and the use of adjuvant cancer therapies. However, cancer patients are often excluded from major clinical trials. Thus, the provision of mechanical thrombectomy (MT) for these patients remains controversial due to their shortened life expectancy and frail overall condition. Addressing this clinical challenge, Mohamed N. Elmarawany and colleagues conducted a study to investigate the safety and efficacy of MT in AIS patients with cancer.

Source

This study was conducted by authors including Mohamed N. Elmarawany, Islam El Malky, Sebastian Winklhofer, Mira Katan, Souvik Kar, and Gerasimos Baltsavias from institutions such as the Department of Neuroradiology, University Hospital Zurich, Switzerland, Department of Neurology, South Valley University, Egypt, and the International Neuroscience Institute, Hannover, Germany. The article was published in Neurology: Clinical Practice, Volume 14, 2024, DOI: 10.1212/cpj.0000000000200320.

Methods

This study employed a retrospective cohort design and conducted a meta-analysis.

Study Population

The study included patients who underwent MT for AIS due to LVO from December 2010 to March 2017. Based on cancer history, patients were divided into three groups: a control group with no cancer history, an active malignancy (AM) group, and a history of malignancy (HOM) group without active malignancy. Patients with a history of intracranial malignancy were excluded.

Procedures

1. Inclusion Criteria

   • No hemorrhage on CT scan;
   • Alberta Stroke Program Early CT Score (ASPECTS) ≥ 6;
   • LVO confirmed by CTA;
   • National Institutes of Health Stroke Scale (NIHSS) score > 3;
   • CT perfusion or MRI showing salvageable brain tissue.

2. Treatment Process

   • Single-center, ²⁴⁄₇ MT service;
   • Endovascular mechanical thrombectomy using aspiration (ASP) or stent retriever thrombectomy (SRT).

3. Data Collection and Analysis

   • Collected patient baseline information, complications, occlusion site, IV thrombolysis, procedural times, and functional scores (on-site and 3-month follow-up);
   • Independent neuroradiologists assessed imaging, with treatment success defined as modified Thrombolysis in Cerebral Infarction (TICI) score 2b or 3 after MT;
   • Data analysis using SPSS v.26, with a significance level of 0.05.

Meta-Analysis

Following the PRISMA guidelines, a literature search was conducted in Embase and PubMed databases, selecting 12 studies related to MT outcomes in cancer patients. The meta-analysis focused on the following outcomes:

• Short-term outcomes: Successful recanalization (TICI ≥ 2b), in-hospital mortality, and symptomatic intracranial hemorrhage (SICH).
• Long-term outcomes: Functional independence (3-month mRS = 0–2) and 90-day mortality.

Results

Quantitative Analysis

Baseline Data

The three groups differed significantly in: - Medical history (stroke or TIA: control 7.8% vs AM 10.5% vs HOM 38.5%, p=0.006); - Alcohol consumption (0.9% vs 10.5% vs 0.0%, p=0.04); - Thrombophilia (1.7% vs 15.8% vs 7.7%, p=0.009).

Clinical and Imaging Outcomes

• The AM group had significantly higher rates of primary aspiration and rescue stent retriever use;
• Successful recanalization rates (AM 84.2%; HOM 69.2%; control 76.5%, p=0.623).

Meta-Analysis Results

Short-term Outcomes

• No significant difference in technical success rates and SICH rates between the AM and control groups;
• In-hospital mortality was significantly higher in the AM group.

Long-term Outcomes

• The AM group had significantly lower rates of 3-month functional independence and higher mortality rates.

Conclusions and Implications

The study suggests that while MT is technically feasible in cancer patients, their clinical outcomes are poorer. Despite similar technical success rates and SICH rates, the AM group had higher in-hospital and 90-day mortality rates. These findings indicate the limitations of MT in cancer patients and the need for careful patient selection.

Highlights

• Similar technical success rates of MT between the AM and control groups;
• Higher SICH rates and mortality in cancer patients suggest the complexity of MT in this population and the need for further research.

Limitations

• Small sample size;
• Retrospective design with potential selection bias;
• Lack of detailed cancer types and genetic data.

Summary

Although MT provides a treatment option for cancer-related AIS, the poorer clinical outcomes in these patients warrant further investigation to optimize treatment strategies and improve long-term survival and quality of life.