Predictors of Occult Cancer in Acute Ischemic Stroke Patients

Mortality in acute ischemic stroke patients with new cancer diagnosed during the index hospitalization versus after discharge

BACKGROUND

Early diagnosis of previously unknown cancer (i.e., occult cancer) after an acute ischemic stroke (AIS) could result in faster initiation of cancer therapy and potentially improve clinical outcomes. Our study aimed to compare mortality rates between AIS patients with occult cancer diagnosed during the index stroke hospitalization versus those diagnosed after hospital discharge.

METHODS

Among consecutive AIS patients treated at our stroke center from 2015 through 2020, we identified new cancer diagnoses made within the year after the AIS. We used multivariable Cox regression analyses to evaluate the association between the timing of occult cancer diagnosis (during the AIS hospitalization versus after discharge) and long-term survival.

RESULTS

Of 3894 AIS patients with available long-term follow-up data, 59 (1.5 %) were diagnosed with a new cancer within one year after index stroke. Of these, 27 (46 %) were diagnosed during the index hospitalization and 32 (54 %) were diagnosed after discharge. During a median follow-up of 406 days (interquartile range, 89-1073), 70 % (n = 19) of patients whose cancer was diagnosed during hospitalization had died, compared to 63 % (n = 20) of patients whose cancer was diagnosed after discharge (p= 0.58). In our main multivariable model, there was no difference in long-term mortality between patient groups (adjusted hazard ratio, 1.16; 95 % confidence interval, 0.53-2.52; p= 0.71).

CONCLUSIONS

In this analysis, timing of a new cancer diagnosis after AIS did not seem to influence patients' long-term survival. Given the fairly small number of included patients with previously occult cancer, larger multicenter studies are needed to confirm our results.

Diagnosing cancer-associated ischemic stroke: A systematic review of hematological biomarkers

BACKGROUND AND AIM

Patients suffering from cancer are reported to have an increased risk of ischemic stroke (IS). We aimed to identify cancer-associated biomarkers found to differentiate between IS associated with cancer from those not associated with cancer.

SUMMARY OF REVIEW

We performed a systematic search of PubMed and EMBASE databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The study is reported in PROSPERO (#CRD42022355129). In total, 5563 papers were screened, of which 49 papers were included. Seven biomarkers were identified which had the potential to differentiate between patients who had cancer or stroke or both conditions. D-dimer was the most frequently monitored biomarker, and high levels were significantly associated with cancer-related strokes in (42/44) studies. Fibrinogen was significantly associated with cancer-related strokes in 11/27 studies. A higher level of C-reactive protein, investigated in 19 studies, was associated with cancer-related strokes, but conclusive multivariate analysis was not performed. Finally, the four cancer-associated antigens CA125, CA153, CA199, and carcinoembryonic antigen were only reported on in three to six studies, respectively. These studies all originated from the Guangxi province in China. CA125 was associated with an increased risk of IS in four of six studies.

CONCLUSION

Increased D-dimer seems associated with cancer-related IS. CRP may also be a candidate as a cancer-associated stroke biomarker, but this requires further verification. Fibrinogen and the more specific cancer biomarkers have not yet been proven helpful for detecting cancer-related strokes.

Embolic strokes of undetermined source: a clinical consensus statement of the ESC Council on Stroke, the European Association of Cardiovascular Imaging and the European Heart Rhythm Association of the ESC

One in six ischaemic stroke patients has an embolic stroke of undetermined source (ESUS), defined as a stroke with unclear aetiology despite recommended diagnostic evaluation. The overall cardiovascular risk of ESUS is high and it is important to optimize strategies to prevent recurrent stroke and other cardiovascular events. The aim of clinicians when confronted with a patient not only with ESUS but also with any other medical condition of unclear aetiology is to identify the actual cause amongst a list of potential differential diagnoses, in order to optimize secondary prevention. However, specifically in ESUS, this may be challenging as multiple potential thromboembolic sources frequently coexist. Also, it can be delusively reassuring because despite the implementation of specific treatments for the individual pathology presumed to be the actual thromboembolic source, patients can still be vulnerable to stroke and other cardiovascular events caused by other pathologies already identified during the index diagnostic evaluation but whose thromboembolic potential was underestimated. Therefore, rather than trying to presume which particular mechanism is the actual embolic source in an ESUS patient, it is important to assess the overall thromboembolic risk of the patient through synthesis of the individual risks linked to all pathologies present, regardless if presumed causally associated or not. In this paper, a multi-disciplinary panel of clinicians/researchers from various backgrounds of expertise and specialties (cardiology, internal medicine, neurology, radiology and vascular surgery) proposes a comprehensive multi-dimensional assessment of the overall thromboembolic risk in ESUS patients through the composition of individual risks associated with all prevalent pathologies.

Development of an algorithm for identifying paraneoplastic ischemic stroke in association with lung, pancreatic, and colorectal cancer

Background

Paraneoplastic ischemic stroke has a poor prognosis. We have recently reported an algorithm based on the number of ischemic territories, C-reactive protein (CRP), lactate dehydrogenase (LDH), and granulocytosis to predict the underlying active cancer in a case-control setting. However, co-occurrence of cancer and stroke might also be merely incidental.

Objective

To detect cancer-associated ischemic stroke in a large, unselected cohort of consecutive stroke patients by detailed analysis of ischemic stroke associated with specific cancer subtypes and comparison to patients with bacterial endocarditis.

Methods

Retrospective single-center cohort study of consecutive 1612 ischemic strokes with magnetic resonance imaging, CRP, LDH, and relative granulocytosis data was performed, including identification of active cancers, history of now inactive cancers, and the diagnosis of endocarditis. The previously developed algorithm to detect paraneoplastic cancer was applied. Tumor types associated with paraneoplastic stroke were used to optimize the diagnostic algorithm.

Results

Ischemic strokes associated with active cancer, but also endocarditis, were associated with more ischemic territories as well as higher CRP and LDH levels. Our previous algorithm identified active cancer-associated strokes with a specificity of 83% and sensitivity of 52%. Ischemic strokes associated with lung, pancreatic, and colorectal (LPC) cancers but not with breast and prostate cancers showed more frequent and prominent characteristics of paraneoplastic stroke. A multiple logistic regression model optimized to identify LPC cancers detected active cancer with a sensitivity of 77.8% and specificity of 81.4%. The positive predictive value (PPV) for all active cancers was 13.1%.

Conclusion

Standard clinical examinations can be employed to identify suspect paraneoplastic stroke with an adequate sensitivity, specificity, and PPV when it is considered that the association of ischemic stroke with breast and prostate cancers in the stroke-prone elderly population might be largely incidental.

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.

Malignancy-associated ischemic stroke: Implications for diagnostic and therapeutic workup

BACKGROUND

Patients with malignancies have an increased risk of suffering ischemic stroke via several mechanisms such as coagulation dysfunction and other malignancy-related effects as well as iatrogenic causes. Moreover, stroke can be the first sign of an occult malignancy, termed as malignancy-associated ischemic stroke (MAS). Therefore, timely diagnostic assessment and targeted management of this complex clinical situation are critical.

FINDINGS

Patients with both stroke and malignancy have atypical ages, risk factors, and often exhibit malignancy-related symptoms and multiple lesions on neuroimaging. New biomarkers such as eicosapentaenoic acid and blood mRNA profiles may help in distinguishing MAS from other strokes. In terms of treatment, malignancy should not be considered a contraindication, given comparable rates of recanalization and complications between stroke patients with or without malignancies.

CONCLUSION

In this review, we summarize the latest developments in diagnosing and managing MAS, especially stroke with occult malignancies, and provide new recommendations from recently emerged clinical evidence for diagnostic and therapeutic workup strategies.

Synthetic data in cancer and cerebrovascular disease research: A novel approach to big data

OBJECTIVES

Synthetic datasets are artificially manufactured based on real health systems data but do not contain real patient information. We sought to validate the use of synthetic data in stroke and cancer research by conducting a comparison study of cancer patients with ischemic stroke to non-cancer patients with ischemic stroke.

DESIGN

retrospective cohort study.

SETTING

We used synthetic data generated by MDClone and compared it to its original source data (i.e. real patient data from the Ottawa Hospital Data Warehouse).

OUTCOME MEASURES

We compared key differences in demographics, treatment characteristics, length of stay, and costs between cancer patients with ischemic stroke and non-cancer patients with ischemic stroke. We used a binary, multivariable logistic regression model to identify risk factors for recurrent stroke in the cancer population.

RESULTS

Using synthetic data, we found cancer patients with ischemic stroke had a lower prevalence of hypertension (52.0% in the cancer cohort vs 57.7% in the non-cancer cohort, p<0.0001), and a higher prevalence of chronic obstructive pulmonary disease (COPD: 8.5% vs 4.7%, p<0.0001), prior ischemic stroke (1.7% vs 0.1%, p<0.001), and prior venous thromboembolism (VTE: 8.2% vs 1.5%, p<0.0001). They also had a longer length of stay (8 days [IQR 3-16] vs 6 days [IQR 3-13], p = 0.011), and higher costs associated with their stroke encounters: $11,498 (IQR $4,440 -$20,668) in the cancer cohort vs $8,084 (IQR $3,947 -$16,706) in the non-cancer cohort (p = 0.0061). A multivariable logistic regression model identified 5 predictors for recurrent ischemic stroke in the cancer cohort using synthetic data; 3 of the same predictors identified using real patient data with similar effect measures. Summary statistics between synthetic and original datasets did not significantly differ, other than slight differences in the distributions of frequencies for numeric data.

CONCLUSION

We demonstrated the utility of synthetic data in stroke and cancer research and provided key differences between cancer and non-cancer patients with ischemic stroke. Synthetic data is a powerful tool that can allow researchers to easily explore hypothesis generation, enable data sharing without privacy breaches, and ensure broad access to big data in a rapid, safe, and reliable fashion.

Transient ischemic attacks in patients with active and occult cancer

Background and aim

Paraneoplastic coagulopathy can present as stroke and is associated with specific biomarker changes. Identifying paraneoplastic coagulopathy can help guide secondary prevention in stroke patients, and early cancer detection might improve outcomes. However, unlike ischemic stroke, it remains unclear whether paraneoplastic coagulopathy is associated with transient ischemic attacks (TIA). This study assessed the presence of cancer-related biomarkers in TIA patients and evaluated long-term mortality rates in patients with and without active cancer.

Methods

Active cancer was retrospectively identified in consecutive TIA patients treated at a comprehensive stroke center between 2015 and 2019. An association between the presence of cancer and cancer-related biomarkers was assessed using multivariable logistic regression. Long-term mortality after TIA was analyzed using multivariable Cox regression.

Results

Among 1436 TIA patients, 72 had active cancer (5%), of which 17 were occult (1.2%). Cancer-related TIA was associated with male gender (adjusted odds ratio [aOR] 2.29, 95% CI 1.12-4.68), history of smoking (aOR 2.77, 95% CI 1.34-5.7), elevated D-dimer (aOR 1.77, 95% CI 1.26-2.49), lactate dehydrogenase (aOR 1.003, 95% CI 1.00-1.005), lower leukocyte count (aOR 1.20, 95% CI 1.04-1.38), and lower hemoglobin (aOR 1.02, 95% CI 1.00-1.04). Long-term mortality was associated with both active cancer (adjusted hazard ratios [aHR] 2.47, 95% CI 1.58-3.88) and occult cancer (aHR 3.08, 95% CI 1.30-7.32).

Conclusion

Cancer-related TIA is not uncommon. Biomarkers known to be associated with cancer-related stroke also seem to be present in TIA patients. Early identification would enable targeted treatment strategies and could improve outcomes in this patient population.

The crosstalk between Stroke and Cancer: Incidence of cancer after a first-ever cerebrovascular event in a population-based study

OBJECTIVES

To determine the cancer incidence after the first-ever cerebrovascular event (CVE) and compare it to the cancer incidence in the population from the same region.

METHODS

We evaluated 1069 patients with a first-ever CVE (Ischaemic or haemorrhagic stroke and Transient Ischaemic Attack) from a prospective population registry of stroke and transient focal neurological attacks, diagnosed between 2009 and 2011. We conducted a structured search to identify cancer-related variables and case-fatality for a period of 8 years following CVE. Cancer incidence in CVE patients was compared to the North Region Cancer Registry (RORENO).

RESULTS

We found that 90/1069 (8.4%) CVE patients developed cancer after a first-ever CVE. Overall cancer annual incidence rate was higher after a CVE (820/100,000, 95%CI: 619-1020) than in general population (513/100,000, 95%CI: 508-518). In the 45-54 age group cancer incidence post-CVE was 3.2-fold (RR, 95%CI: 1.6-6.4) higher compared to the general population, decreasing gradually in older age-groups. Median time between CVE and cancer was 3.2 years (IQR = 1.4-5.2). Lower respiratory tract and colorectal were the most frequent cancer types. In univariable models, male sex (sHR = 1.78, 95%CI: 1.17-2.72, p = 0.007), tobacco use (sHR = 2.04, 95%CI: 1.31-3.18, p = 0.002) and peripheral artery disease (sHR = 2.37, 95%CI: 1.10-5.13, p = 0.028) were associated to higher cancer risk after CVE. After adjustment, tobacco use (sHR = 1.84, 95%CI: 1.08-3.14, p = 0.026) remained associated to a higher risk of cancer.

CONCLUSIONS

At the population level, patients presenting a first-ever CVE have higher cancer incidence, that is particularly prominent in younger age-groups. Higher cancer incidence, delayed cancer diagnosis and increased mortality post-CVE warrants further research on long-term cancer surveillance in first-ever CVE survivors.

Cancer Prediction With Machine Learning of Thrombi From Thrombectomy in Stroke: Multicenter Development and Validation

BACKGROUND

We aimed to develop and validate machine learning models to diagnose patients with ischemic stroke with cancer through the analysis of histopathologic images of thrombi obtained during endovascular thrombectomy.

METHODS

This was a retrospective study using a prospective multicenter registry which enrolled consecutive patients with acute ischemic stroke from South Korea who underwent endovascular thrombectomy. This study included patients admitted between July 1, 2017 and December 31, 2021 from 6 academic university hospitals. Whole-slide scanning was performed for immunohistochemically stained thrombi. Machine learning models were developed using transfer learning with image slices as input to classify patients into 2 groups: cancer group or other determined cause group. The models were developed and internally validated using thrombi from patients of the primary center, and external validation was conducted in 5 centers. The model was also applied to patients with hidden cancer who were diagnosed with cancer within 1 month of their index stroke.

RESULTS

The study included 70 561 images from 182 patients in both internal and external datasets (119 patients in internal and 63 in external). Machine learning models were developed for each immunohistochemical staining using antibodies against platelets, fibrin, and erythrocytes. The platelet model demonstrated consistently high accuracy in classifying patients with cancer, with area under the receiver operating characteristic curve of 0.986 (95% CI, 0.983-0.989) during training, 0.954 (95% CI, 0.937-0.972) during internal validation, and 0.949 (95% CI, 0.891-1.000) during external validation. When applied to patients with occult cancer, the model accurately predicted the presence of cancer with high probabilities ranging from 88.5% to 99.2%.

CONCLUSIONS

Machine learning models may be used for prediction of cancer as the underlying cause or detection of occult cancer, using platelet-stained immunohistochemical slide images of thrombi obtained during endovascular thrombectomy.

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.

The investigation on the hypercoagulability of hepatocellular carcinoma-related cerebral infarction with thromboelastography

AIM

To investigate the hypercoagulability of hepatocellular carcinoma (HCC)-related cerebral infarction (HCRCI) with thromboelastography (TEG).

METHODS

A multicenter prospective study was conducted in HCRCI patients, HCC patients without cerebral infarction, and acute cerebral infarction (ACI) patients without HCC between January 2016 and December 2019. TEG parameters and laboratory and clinical data were collected and compared among the three groups. To confirm the independent risk factors of HCRCI, multivariate analyses were conducted. Receiver operating characteristic (ROC) curves were utilized to evaluate the area under the curve (AUC) plotted by each independent risk factor.

RESULTS

There were 38 patients recruited in the HCRCI group, and 152 patients were recruited to the HCC group and the ACI group. The levels of plasma neutrophil count, D-dimer, α-fetoprotein (AFP), carcinoembryonic antigen, and maximum amplitude (MA)-a parameter of TEG-were significantly higher in the HCRCI group than HCC and ACI groups. Multivariate logistic regression analysis showed that increased neutrophile count, D-dimer, AFP, and MA were independently associated with HCRCI. ROC curve analysis showed first that AUC of MA for HCRCI was .875, which was larger than the other risk factors, and second that the optimal cutoff value for MA was 61.35, with a sensitivity of 89.50% and specificity of 66.40%.

CONCLUSION

It was suggested that TEG disclosed that the pathogenesis of HCRIC is exactly related to the hypercoagulability. And with a cutoff value of MA equaling to 61.35, TEG facilitates clinicians to identify HCC patients at high risk of HCRIC.

Current perspectives on the clinical management of cryptogenic stroke

INTRODUCTION

Cryptogenic stroke is a heterogeneous entity defined as an ischemic stroke for which no probable cause is identified despite thorough diagnostic evaluation. Since about a quarter of all ischemic strokes are classified as cryptogenic, it is a commonly encountered problem for providers as secondary stroke prevention is guided by stroke etiology.

AREAS COVERED

In this review, the authors provide an overview of stroke subtype classification schemes and diagnostic evaluation in cryptogenic stroke. They then detail putative cryptogenic stroke mechanisms, their therapeutic implications, and ongoing research. This review synthesizes the available evidence on PubMed up to December 2022.

EXPERT OPINION

Cryptogenic stroke is an evolving concept that changes with ongoing research. Investigations are focused on improving our diagnostic capabilities and solidifying useful constructs within cryptogenic stroke that could become therapeutically targetable subgroups within an otherwise nonspecific entity. Advances in technology may help move specific proposed cryptogenic stroke mechanisms from undetermined to known source of ischemic stroke.

A risk model for prediction of diagnosis of cancer after ischemic stroke

It remains controversial which characteristics may predict occult cancer in stroke patients. Characteristics of patients with ischemic stroke registered in the Zurich Swiss Stroke Registry (2014 to 2016) were tested for associations with cancer diagnosis after stroke with consideration of death as competing risk for cancer diagnosis. Among 1157 patients, 34 (3%) and 55 patients (5%) were diagnosed with cancer within 1 and 3 years after stroke. Levels of white blood cells (WBC) > 9,600/µl (subdistribution hazard ratio (SHR) 3.68, p = 0.014), platelets > 400,000/µl (SHR 7.71, p = 0.001), and d-dimers ≥ 3 mg/l (SHR 3.67, p = 0.007) were independently associated with cancer diagnosis within 1 year after stroke. Occurrence of ischemic lesions in ≥ 2 vascular territories not attributed to cardioembolic etiology was associated with cancer diagnosed within 1 year after stroke in univariable analysis (SHR 3.69, p = 0.001). The area under the curve of a score from these parameters (score sum 0-4) was 0.73. A score of ≥ 2 had a sensitivity of 43% and specificity of 92% for prediction of cancer diagnosis within 1 year after stroke. We suggest further validation of a score of WBC, platelets, d-dimers and multiple ischemic lesions without cardioembolic stroke etiology for prediction of cancer diagnosis after stroke.

Absence of susceptibility vessel sign and hyperdense vessel sign in patients with cancer-related stroke

Background and aim

Identification of paraneoplastic hypercoagulability in stroke patients helps to guide investigations and prevent stroke recurrence. A previous study demonstrated an association between the absence of the susceptibility vessel sign (SVS) on brain MRI and active cancer in patients treated with mechanical thrombectomy. The present study aimed to confirm this finding and assess an association between the absence of the hyperdense vessel sign (HVS) on head CT and active cancer in all stroke patients.

Methods

SVS and HVS status on baseline imaging were retrospectively assessed in all consecutive stroke patients treated at a comprehensive stroke center between 2015 and 2020. Active cancer, known at the time of stroke or diagnosed within 1 year after stroke (occult cancer), was identified. Adjusted odds ratios (aOR) and their 95% confidence interval (CI) for the association between the thrombus imaging characteristics and cancer were calculated using multivariable logistic regression.

Results

Of the 2,256 patients with thrombus imaging characteristics available at baseline, 161 had an active cancer (7.1%), of which 36 were occult at the time of index stroke (1.6% of the total). The absence of SVS was associated with active cancer (aOR 3.14, 95% CI 1.45-6.80). No significance was reached for the subgroup of occult cancer (aOR 3.20, 95% CI 0.73-13.94). No association was found between the absence of HVS and active cancer (aOR 1.07, 95% CI 0.54-2.11).

Conclusion

The absence of SVS but not HVS could help to identify paraneoplastic hypercoagulability in stroke patients with active cancer and guide patient care.

Cancer-associated stroke

Background. Systemic cancer and stroke are the most common diseases and the frequent death factors in older people worldwide. The relationship between cancer and stroke is complex, since cancer leads to an increased risk of stroke through specific pathophysiological mechanisms. Purpose. Analyzing possible mechanisms of development of cancer-associated stroke, strategies of diagnosis and treatment. Materials and methods. The contributions were selected based on PubMed (https://pubmed.ncbi.nlm.nih.gov/), Clinical Key Elsevier (https://www.clinicalkey.com), Cochrane Library (https://www.cochranelibrary.com/) and GoogleScholar (https://scholar.google.com/) databases published from 2012 to 2022, dealing with cancer-associated stroke. Results and discussion. There are several underlying pathophysiological mechanisms of cancer-associated stroke, which may be directly related to cancer or caused by cancer complications. The most common ones are intravascular cancer coagulopathy, non-bacterial thrombotic endocarditis, a direct impact of the tumor on the vascular system or therapeutic and diagnostic interventions for the treatment of cancer that is chemotherapy, radiation therapy complications, as well as activation of the usual mechanisms of stroke, atherosclerosis in particular. The risk of stroke is also related to cancer aggressiveness. The characteristic features of cancer-associated stroke which is related to cancer coagulopathy are multiple lesions in various arterial areas, as well as laboratory data indicating coagulopathy in the form of increased level of D-dimer, elevated C-reactive protein, low hematocrit. Conclusions. Cancer leads to an increased risk of stroke due to specific pathophysiological mechanisms. These mechanisms are multiple and complex, but the most well-known and widespread is cancer intravascular coagulopathy, which has specific laboratory biomarkers. Numerous studies continue investigating the factors associated with coagulopathy in stroke patients, cancer characteristics, and evaluation of biological markers of stroke-causing intravascular coagulopathy, as well as monitoring the effects of anticoagulation therapy in patients with cancer-associated stroke.

Neurovascular Manifestations of Iron-Deficient Anemia: Narrative Review and Practical Reflections through a Teaching Case

Anemia is one of the most frequent diseases worldwide, affecting one-third of the general population. Anemia in general and in particular, iron-deficient anemia (IDA), has been associated to a higher risk of thrombotic manifestations, including ischemic stroke and cerebral venous thrombosis (CVT), as well as systemic extra-cerebral arterial and venous thrombosis. Despite these data, anemia is seldom considered as an etiological factor of stroke. An individual case encompassing all known neurovascular and systemic arterial and venous thrombotic manifestations related to IDA is presented with the focus on clinical reasoning issues in the diagnostic pathways, starting from the neuroradiological signs. The main questions have been identified and addressed in a narrative review of the most relevant data in the literature from a pragmatic and clinical viewpoint. The presented case concerns a 46-year-old man admitted to the Stroke Unit because of acute ischemic stroke with multiple thrombi in large intracranial and extracranial vessels, multifocal ischemic lesions in several arterial territories and the concurrent finding of asymptomatic CVT, pulmonary embolism with lung infarction and aortic thrombosis. An extended diagnostic work-up excluded the main etiologies (arterial dissection, cardiac embolism, genetic and acquired prothrombotic disorders, such as cancer and antiphospholipid syndrome), except for a severe IDA, such as to require blood transfusions followed by anticoagulant therapy for the several thrombotic manifestations. Neuroimaging and systemic vascular findings have been analyzed, and the main issues proposed by the case in the diagnostic pathway have been identified and discussed in a pragmatic clinical road map reviewing the data provided by the literature. Conclusions: IDA is a common but treatable condition that, independently or synergically, may increase the risk of thrombotic events. The diagnostic and therapeutic approach has not yet been defined, and each case should be individually addressed in a pragmatic clinical road map.

Cancer and stroke: What do we know and where do we go?

Cancer is an increasingly recognized cause for ischemic stroke, with recent acknowledgement of cancer-related stroke as an emerging stroke subtype with unique pathophysiologic mechanisms. In addition, cancer-related stroke may differ from stroke in the general population as cancer patients may not receive guideline-recommended stroke care, and the occurrence of stroke may also preclude patients from receiving optimal cancer treatments. Due to the high degree of morbidity and mortality associated with both conditions, understanding the relationship between stroke and cancer is crucial. In this narrative review, we discuss the association between cancer and stroke, the unique pathophysiologic mechanisms underlying this phenomenon, treatment options including acute reperfusion therapies and secondary prevention strategies, compare outcomes between cancer-related stroke and stroke in the general population, and review new and emerging evidence in this field.

Absence of Susceptibility Vessel Sign in Patients With Malignancy-Related Acute Ischemic Stroke Treated With Mechanical Thrombectomy

Background and Purpose

Clots rich in platelets and fibrin retrieved from patients with acute ischemic stroke (AIS) have been shown to be independently associated with the absence of the susceptibility vessel sign (SVS) on MRI and active malignancy. This study analyzed the association of SVS and the presence of active malignancy in patients with AIS who underwent mechanical thrombectomy (MT).

Methods

This single-center, retrospective, and cross-sectional study included consecutive patients with AIS with admission MRI treated with MT between January 2010 and December 2018. SVS status was evaluated on susceptibility-weighted imaging. Adjusted odds ratios (aORs) were calculated to determine the association between absent SVS and the presence of active or occult malignancy. The performance of predictive models incorporating and excluding SVS status was compared using areas under the receiver operating characteristics curve (auROC).

Results

Of 577 patients with AIS with assessable SVS status, 40 (6.9%) had a documented active malignancy and 72 (12.5%) showed no SVS. The absence of SVS was associated with active malignancy (aOR 4.85, 95% CI 1.94–12.11) or occult malignancy (aOR 11.42, 95% CI 2.36–55.20). The auROC of predictive models, including demographics and common malignancy biomarkers, was higher but not significant (0.85 vs. 0.81, p = 0.07) when SVS status was included.

Conclusion

Absence of SVS on admission MRI of patients with AIS undergoing MT is associated with malignancy, regardless of whether known or occult. Therefore, the SVS might be helpful in detecting paraneoplastic coagulation disorders and occult malignancy in patients with AIS.

Cancer and stroke: commonly encountered by clinicians, but little evidence to guide clinical approach

The association between stroke and cancer is well-established. Because of an aging population and longer survival rates, the frequency of synchronous stroke and cancer will become even more common. Different pathophysiologic mechanisms have been proposed how cancer or cancer treatment directly or via coagulation disturbances can mediate stroke. Increased serum levels of D-dimer, fibrin degradation products, and CRP are more often seen in stroke with concomitant cancer, and the clot retrieved during thrombectomy has a more fibrin- and platelet-rich constitution compared with that of atherosclerotic etiology. Multiple infarctions are more common in patients with active cancer compared with those without a cancer diagnosis. New MRI techniques may help in detecting typical patterns seen in the presence of a concomitant cancer. In ischemic stroke patients, a newly published cancer probability score can help clinicians in their decision-making when to suspect an underlying malignancy in a stroke patient and to start cancer-screening studies. Treating stroke patients with synchronous cancer can be a delicate matter. Limited evidence suggests that administration of intravenous thrombolysis appears safe in non-axial intracranial and non-metastatic cancer patients. Endovascular thrombectomy is probably rather safe in these patients, but probably futile in most patients placed on palliative care due to their advanced disease. In this topical review, we discuss the epidemiology, pathophysiology, and prognosis of ischemic and hemorrhagic strokes as well as cerebral venous thrombosis and concomitant cancer. We further summarize the current evidence on acute management and secondary preventive therapy.

Development of a score for prediction of occult malignancy in stroke patients (occult-5 score)

BACKGROUND AND PURPOSE

Malignancy associated acute ischemic stroke (AIS) requires specific diagnostic work-up, treatment and prevention to improve outcome. This study aimed to develop a biomarker-based score for prediction of occult malignancy in AIS patients.

METHODS

Single-center cross-sectional study including consecutive AIS patients treated between July 2017 and November 2018. Patients with active malignancy at presentation, or diagnosed within 1 year thereafter and patients free of malignancy, were included and malignancy associated biomarkers were assessed. LASSO analyses of logistic regression were performed to determine biomarkers predictive of active malignancy. Predictors were derived from a predictive model for active malignancy. A comparison between known and unknown (=occult) malignancies when the index stroke occurred was used to eliminate variables not associated with occult malignancy. A predictive score (OCCULT-5 score) for occult malignancy was developed based on the remaining variables.

RESULTS

From 1001 AIS patients, 61 (6%) presented an active malignancy. Thirty-nine (64%) were known and 22 (36%) occult. Five variables were included in the final OCCULT-5 score: age ≥ 77 years, embolic stroke of undetermined source, multi-territorial infarcts, D-dimer levels ≥ 820 µ/gL, and female sex. A score of ≥ 3 predicted an underlying occult malignancy with a sensitivity of 64%, specificity of 73%, positive likelihood ratio of 2.35 and a negative likelihood ratio of 0.50.

CONCLUSIONS

The OCCULT-5 score might be useful to identify patients with occult malignancy. It may thus contribute to a more effective and timely treatment and thus lead to a positive impact on overall outcome.

Discrepancies between clinical and autopsy findings in patients who had an acute stroke

Objectives

According to international observations, the incidence of clinical autopsies is declining worldwide, plummeting below 5% in the USA and many European countries. It is an unfavourable trend as, in 7%–12% of cases, recent clinicopathological studies found discrepancies that might have changed the therapy or the outcome if known premortem. As previous large-scale observations have examined varied patient populations, we aimed to focus on the differences between the clinical and pathological diagnostic findings in only patients who had a stroke.

Material and methods

We assessed the postmortem non-neuropathological and neuropathological findings of 534 consecutive patients who had a stroke who passed away. Systemic neoplasms, pneumonias, thromboembolisms and haemorrhagic transformations revealed only by autopsy were considered severe abnormalities; in addition, benign abnormalities important from an educational or scientific point of view were also recorded.

Results

In 26 of the 534 cases (4.9%), the presence of systemic neoplasms had already been confirmed in the clinical stage; however, 8 (1.5%) malignant tumours were only detected during autopsy. Also, 80 (15%) thromboembolic events, 73 (13.6%) pneumonias and 66 (18%) haemorrhagic transformations were only diagnosed at autopsy. Longer hospital stay (from admission to death) resulted in fewer discrepancies between clinical and autopsy diagnosis of thromboembolic events and pneumonias (p<0.01). In 169 cases, benign findings were detected.

Conclusions

While the type of acute stroke is reliably diagnosed with imaging techniques, postmortem autopsies are also important in patients who had a stroke as autopsies may reveal clinically silent diseases (eg, tumour), and contribute to knowing the actual incidence of stroke-related thromboembolic and pneumonia complications.

Serum Alkaline Phosphatase in Cryptogenic Stroke Cases with Active Cancer

Objective We assessed the relationship between the levels of serum alkaline phosphatase, which is often increased with biliary obstruction and bone metastasis, and active cancer in patients with cryptogenic stroke. Methods Serum alkaline phosphatase levels in patients with cryptogenic stroke sampled upon admission were measured using the Japan Society of Clinical Chemistry method used in Japan. Active cancer was defined as a new diagnosis, treatment, progression, or recurrence within six months before admission or metastatic cancer. Multivariate logistic regression analyses were performed to explore the relationship between serum alkaline phosphatase and active cancer in these patients. Results Among the 249 patients classified as having cryptogenic stroke, 64 had active cancer. Patients with cryptogenic stroke with active cancer had significantly higher serum alkaline phosphatase levels (486±497 vs. 259±88.2 U/L; p<0.001) than those without cancer. Multivariate logistic analysis revealed that serum alkaline phosphatase levels ≥286 U/L were associated with cryptogenic stroke with active cancer [odds ratio (OR), 2.669, 95% confidence interval (CI), 1.291-5.517; p=0.008] independent of age ≤70 years old (OR, 3.303, 95% CI, 1.569-6.994; p=0.002), male sex (OR, 0.806, 95% CI, 0.380-1.710; p=0.573), and serum D-dimer levels ≥2.6 μg/mL (OR, 18.78, 95% CI, 8.130-43.40; p<0.001). Conclusion In patients with cryptogenic stroke, high serum alkaline phosphatase levels may be related to active cancer.

Neurologic Complications in Patients with Cancer

Neurologic symptoms are commonly seen in patients with cancer and can be among the most challenging to diagnose and manage. It is often difficult to determine if new neurologic symptoms are secondary to direct effects of a malignant lesion, systemic complications of disease, paraneoplastic disorders, or side effects of cancer treatment itself. However, early diagnosis and treatment of each of these conditions can improve patients' quality of life and long-term functional outcomes. In this review, we describe a systematic approach to the diagnosis of new neurologic symptoms in patients with known malignancy. We have categorized the neurologic complications of cancer through a mechanistic approach, with an emphasis on ascertaining underlying pathophysiology to guide treatment choice. This review focuses on the acute neurologic complications of cancer that require hospital admission.

Hemostatic biomarkers in occult cancer and cancer risk prediction

Cancer patients present with abnormalities of coagulation tests, reflecting a hypercoagulable state, often asso- ciated with a high incidence of thrombotic complications and poor disease prognosis. Different degrees of blood clotting abnormalities are described in diverse cancers, depending on tumor types and stage. The mechanisms of hemostasis that are critically involved in thrombosis are also implicated in tumor progression, angiogenesis, and metastatic spread. In this review, we summarize the results of published studies and focus on ongoing research and future directions of clotting factors and clotting activation bioproducts as biomarkers for cancer disease diagnosis and in cancer risk prediction.

Effectiveness of mechanical thrombectomy in cancer-related stroke and associated factors with unfavorable outcome

Background

The effectiveness of mechanical thrombectomy (MT) in cancer-related stroke (CRS) is largely unknown. This study aims to investigate the clinical and radiological outcomes of MT in CRS patients. We also explored the factors that independently affect functional outcomes of patients with CRS after MT.

Methods

We retrospectively reviewed 341 patients who underwent MT after acute ischemic stroke onset between May 2014 and May 2020. We classified the patients into CRS (n = 34) and control (n = 307) groups and compared their clinical details. Among CRS patients, we analyzed the groups with and without good outcomes (3-months modified Rankin scale [mRS] score 0, 1, 2). Multivariate analysis was performed to investigate the independent predictors of unfavorable outcomes in patients with CRS after MT.

Results

A total of 341 acute ischemic stroke patients received MT, of whom 34 (9.9%) had CRS. Although the baseline National institute of health stroke scale (NIHSS) score and the rate of successful recanalization was not significantly different between CRS patients and control group, CRS patients showed more any cerebral hemorrhage after MT (41.2% vs. controls 23.8%, p = 0.037) and unfavorable functional outcome at 3 months (CRS patients median 3-month mRS score 4, interquartile range [IQR] 2 to 5.25 vs. controls median 3-month mRS score 3, IQR 1 to 4, [p = 0.026]). In the patients with CRS, elevated serum D-dimer level and higher baseline NIHSS score were independently associated with unfavorable functional outcome at 3 months (adjusted odds ratio [aOR]: 1.524, 95% confidence interval [CI]: 1.043–2.226; aOR: 1.264, 95% CI: 1.010–1.582, respectively).

Conclusions

MT is an appropriate therapeutic treatment for revascularization in CRS patients. However, elevated serum D-dimer levels and higher baseline NIHSS scores were independent predictors of unfavorable outcome. Further research is warranted to evaluate the significance of these predictors.

Case Report: Brain Metastasis Confined to the Infarcted Area Following Stroke

Background: Ischemic stroke and cancer are frequent in the elderly and are the two common causes of death and disability. They are related to each other, and cancer may lead to ischemic stroke and vice versa. If patients with cancer exhibited recurrent acute neurological deficits after index stroke, a cancer-related stroke could be considered. However, a brain metastasis is another common cause of neurological complications and has a poor prognosis in patients with ischemic stroke and comorbid cancer. Here, we report a rare case of metastatic cancer that occurred after index stroke in a patient with renal cell carcinoma (RCC) and unusual imaging findings. Through the case, we discuss the pathophysiology and probable predisposing factors for metastatic disease in areas of infarction. Case Presentation: A 48-year-old man presented with sudden onset of left facial palsy and hemiparesis. He had a history of hypertension and RCC with pulmonary metastases treated with radical nephrectomy and chemotherapy. Brain magnetic resonance imaging (MRI) revealed multiple scattered acute infarctions in the right insular, frontal, parietal, and left occipital cortices. There were no definite sources of embolism. Eight months after the index stroke, he presented with subacute onset of progressive left hemiparesis. He had no focal neurological deficits except left-sided weakness and left nasolabial fold blunting. MRI scan demonstrated partial diffusion restriction on the right frontotemporal cortices without decline of apparent diffusion coefficient values on the corresponding lesions and T1 hypointensities and T2 hyperintensities with perilesional vasogenic edema on the right insular, frontal, parietal, and left occipital cortices, indicative of brain metastases confined to the area of previous infarctions. Conclusions: Cerebral infarctions can cause neovascularization and disruption of the blood-brain barrier. Moreover, the compartmentalized cavity formed by the ischemic injury may accept a large volume of metastatic tumor cells. Such an altered microenvironment of infarcted tissue would be suitable for the colonization and proliferation of metastatic seed. Further, brain metastases should be considered, in addition to recurrence, when new focal neurological deficits develop in patients with ischemic stroke and comorbid cancer.

Cancer and Embolic Stroke of Undetermined Source

One-quarter to one-third of ischemic strokes have no established mechanism after standard diagnostic evaluation and are classified as embolic stroke of undetermined source (ESUS). Failure of randomized trials to demonstrate a benefit of direct oral anticoagulants over aspirin for the treatment of ESUS as a single homogeneous entity has led to renewed interest by stroke experts to divide ESUS into subgroups. Emerging data suggest that active cancer, which is present in 5% to 10% of patients with ESUS, is a distinct and important subgroup of ESUS with unique clinical characteristics, underlying pathophysiologies, and treatment and prognostic considerations. Furthermore, the prevalence of cancer-related ESUS is expected to increase as patients with cancer, even those with distant metastases, survive longer due to improvements in cancer treatments. In this topical review, we examine the epidemiological link between ESUS and cancer, the clinical features and potential mechanistic underpinnings of ESUS with cancer (with a focus on novel biomarkers and their relationship to recurrent stroke and other thromboembolic events), and the potential treatment strategies for cancer-related ESUS. We include a critical appraisal of existing data and ongoing or planned clinical trials of different antithrombotic approaches. As cancer-related ESUS is a dynamic disease with variable course, we recommend close collaboration between neurologists and oncologists to develop individualized management plans.

Towards biomarkers for outcomes after pancreatic ductal adenocarcinoma and ischaemic stroke, with focus on (co)-morbidity and ageing/cellular senescence (SASKit): protocol for a prospective cohort study

INTRODUCTION

Ageing-related processes such as cellular senescence are believed to underlie the accumulation of diseases in time, causing (co)morbidity, including cancer, thromboembolism and stroke. Interfering with these processes may delay, stop or reverse morbidity. The aim of this study is to investigate the link between (co)morbidity and ageing by exploring biomarkers and molecular mechanisms of disease-triggered deterioration in patients with pancreatic ductal adenocarcinoma (PDAC) and (thromboembolic) ischaemic stroke (IS).

METHODS AND ANALYSIS

We will recruit 50 patients with PDAC, 50 patients with (thromboembolic) IS and 50 controls at Rostock University Medical Center, Germany. We will gather routine blood data, clinical performance measurements and patient-reported outcomes at up to seven points in time, alongside in-depth transcriptomics and proteomics at two of the early time points. Aiming for clinically relevant biomarkers, the primary outcome is a composite of probable sarcopenia, clinical performance (described by ECOG Performance Status for patients with PDAC and the Modified Rankin Scale for patients with stroke) and quality of life. Further outcomes cover other aspects of morbidity such as cognitive decline and of comorbidity such as vascular or cancerous events. The data analysis is comprehensive in that it includes biostatistics and machine learning, both following standard role models and additional explorative approaches. Prognostic and predictive biomarkers for interventions addressing senescence may become available if the biomarkers that we find are specifically related to ageing/cellular senescence. Similarly, diagnostic biomarkers will be explored. Our findings will require validation in independent studies, and our dataset shall be useful to validate the findings of other studies. In some of the explorative analyses, we shall include insights from systems biology modelling as well as insights from preclinical animal models. We anticipate that our detailed study protocol and data analysis plan may also guide other biomarker exploration trials.

ETHICS AND DISSEMINATION

The study was approved by the local ethics committee (Ethikkommission an der Medizinischen Fakultät der Universität Rostock, A2019-0174), registered at the German Clinical Trials Register (DRKS00021184), and results will be published following standard guidelines.

Frequency and predictors of occult cancer in ischemic stroke: A systematic review and meta-analysis

BACKGROUND

The optimal approach for cancer screening after an ischemic stroke remains unclear.

AIMS

We sought to summarize the existing evidence regarding the frequency and predictors of cancer after an ischemic stroke.

SUMMARY OF REVIEW

We searched seven databases from January 1980 to September 2019 for articles reporting malignant tumors and myeloproliferative neoplasms diagnosed after an ischemic stroke (PROSPERO protocol: CRD42019132455). We screened 15,400 records and included 51 articles. The pooled cumulative incidence of cancer within one year after an ischemic stroke was 13.6 per thousand (95% confidence interval [CI], 5.6-24.8), higher in studies focusing on cryptogenic stroke (62.0 per thousand; 95% CI, 13.6-139.3 vs 9.6 per thousand; 95% CI, 4.0-17.3; p = 0.02) and those reporting cancer screening (39.2 per thousand; 95% CI, 16.4-70.6 vs 7.2 per thousand; 95% CI, 2.5-14.1; p = 0.003). Incidence of cancer after stroke was generally higher compared to people without stroke. Most cases were diagnosed within the first few months after stroke. Several predictors of cancer were identified, namely older age, smoking, and involvement of multiple vascular territories as well as elevated C-reactive protein and d-dimers.

CONCLUSIONS

The frequency of incident cancer after an ischemic stroke is low, but higher in cryptogenic stroke and after cancer screening. Several predictors may increase the yield of cancer screening after an ischemic stroke. The pooled incidence of post-stroke cancer is likely underestimated, and larger studies with systematic assessment of cancer after stroke are needed to produce more precise and valid estimates.

Ischemic stroke: A paradoxical manifestation of cancer

INTRODUCTION

Approximately 5-10 % of the patients with cryptogenic stroke have an underlying malignancy. Stroke as a complication of cancer increases the morbidity and mortality among cancer patients, leading to increased disability and healthcare costs.

OBJECTIVE

To provide elements to guide physicians for when to suspect and evaluate for cancer in stroke patients.

DEVELOPMENT

We performed a narrative review, portrayed in a question-answer format, to report relevant aspects of cancer stroke patients in the clinical practice and provide a guide based on the state-of-the-art literature. Conventional stroke mechanisms are only found in a fraction of patients with cancer. Although cardiovascular risk factors play an important role in both cancer and stroke pathogenesis, the recognition of more specific cancer-associated risk factors raises clinical suspicion for occult malignancy. We also expose the main type location and histology of tumors that are most commonly associated with stroke as well as potential blood biomarkers and current treatment considerations in the scenario of cancer associated stroke.

CONCLUSION

Subjects with active cancer are a patient population at increased risk for developing an ischemic stroke. Cryptogenic stroke patients have a higher risk of cancer diagnosis in the following 6-12 months. We recommend a multidisciplinary approach considering the high probability of a hidden malignancy and running a comprehensive evaluation including neurologic imaging, serological biomarkers and tight follow up.

Time of Stroke Onset in Coronavirus Disease 2019 Patients Around the Globe: A Systematic Review and Analysis

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Stroke cases continue to rise in the COVID-19 pandemic.

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Stroke presents late in severe COVID-19 patients and early in mild cases.

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Patients with large vessel occlusion were younger and had higher NIHSS.

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Hypercoagulability and inflammation in COVID-19 are related to stroke.

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Other cause should be considered as a stroke etiology in COVID-19 patients.

Introduction

Coronavirus disease 2019 has been associated with stroke, particular characteristics of these patients are not fully understood. The adequate management of these patients depends on the comprehension of factors such as temporality, clinical presentation and etiology. We hypothesize there is an important temporal relationship between COVID-19 severity and stroke onset.

Methods

a systematic review of the available literature was conducted using Pubmed and Scopus, studies reporting patients with Coronavirus disease 19 and stroke were included. Clinical, sociodemographic and laboratory characteristics of patients were extracted and analyzed.

Results

Forty-seven studies and 176 patients were included, with a mean age of 63.1 years (SD= 16 n=122), most of them were males (63.2% n=171). The most frequent etiology was cryptogenic 40.9% n=66), and a mean National Institute of Health Stroke Scale of 14.4 points was found (SD= 8.6 n=73). Large vessel occlusion was reported in 65.9% patients (n=91) and these patients were younger with greater stroke severity. D-dimer, C-reactive protein, fibrinogen, ferritin and lactate dehydrogenase were elevated in most patients with reported findings. Most patients had severe Coronavirus disease 2019. The mean time from onset of respiratory symptoms to stroke was 9 days (SD=9.9), the shortest time was noted in those with mild and moderate disease.

Conclusions

There is a trend between the severity of Coronavirus disease 2019 and time to stroke onset. Also, age and stroke severity were found to be related to the development of large vessel occlusion. Inflammation and hypercoagulability markers are elevated in this disease, we propose to not discard hypercoagulability secondary to severe acute respiratory syndrome-coronavirus-2 as an underlying cause of stroke in these patients.

Profiling of the Risk Factors and Designing of a Model to Identify Ischemic Stroke in Patients with Non-Hodgkin Lymphoma: A Multicenter Retrospective Study

BACKGROUND

The occurrence of ischemic stroke in patients with non-Hodgkin lymphoma (NHL) is not well understood. This study aimed to determine independent risk factors to identity ischemic stroke in non-Hodgkin lymphoma-associated ischemic stroke (NHLAIS) patients.

METHODS

This retrospective study was conducted on NHLAIS patients and age- and gender-matched NHL patients. We collected clinical data of patients in both groups and used multiple logistic regression analysis to identify independent risk factors for NHLAIS. A receiver operating characteristic (ROC) analysis was used to establish an identification model based on potential risk factors of NHLAIS.

RESULTS

Sixty-three NHLAIS patients and 63 NHL patients were enrolled. Stage III/IV (58/63, 92.1%) and multiple arterial infarcts (44/63, 69.8%) were common among NHLAIS patients. Notably, NHLAIS patients had higher levels of serum fibrinogen (FIB), D-dimer, and ferritin (SF) and prolonged thromboplastin time and prothrombin time (PT) compared with NHL patients (all p < 0.05). Elevated FIB, D-dimer, and SF and prolonged PT were independent risk factors for NHLAIS. The area under the ROC curve of the identification model of NHLAIS patients was largest compared to that of other risk factors (0.838, 95% confidence interval: 0.759-0.899) (p < 0.05).

CONCLUSION

This study reveals that elevated serum FIB, D-dimer, and SF and prolonged PT are potential independent risk factors of NHLAIS. The identification model established in this study may help monitor NHL patients who are at high risk of developing NHLAIS.

Independent risk factors and the potential predictors of bladder cancer-related ischemic stroke

Objective

To investigate the independent risk factors and potential predictors of bladder cancer-related ischemic stroke (BCRIS).

Methods

This was a multi-center retrospective study including patients with active bladder cancer and acute ischemic stroke without traditional stroke risk factors (BCRIS group), and sex- and age-matched patients with active bladder cancer alone (control group). Data were collected between January 2006 and December 2018. Uni- and multivariate analyses were performed to identify independent risk factors for BCRIS. The predictive performance of these risk factors was assessed using receiver operating characteristic (ROC) curves.

Results

Records were retrospectively reviewed from 60 BCRIS patients and 120 bladder cancer controls. Univariate analysis revealed that serum D-dimer and carcinoembryonic antigen (CEA) levels and the platelet and neutrophil counts were significantly higher in BCRIS patients compared with controls. Multivariate analysis identified the three above-mentioned variables as independent risk factors for BCRIS. The product of all three factors gave the largest area under the ROC curve.

Conclusions

Elevated serum D-dimer and CEA levels and increased platelet count were independent risk factors for BCRIS, and the cut-off value based on the product of the three independent risk factors (≥2,640,745.29) could serve as a potential predictor of BCRIS.

Prevalence and risk of occult cancer in stroke

OBJECTIVES

Cancer is associated with higher risk of stroke. Whether this translates into higher risk of cancer in stroke of an extent calling for cancer screening in stroke is unclear. We investigated prevalence and risk of occult cancer in stroke compared to the background population without history of stroke.

MATERIALS AND METHODS

All patients >40 years of age with incident stroke in Denmark 2003-2015 were identified through the Danish Stroke Registry (n = 85 893) and matched 1:10 on age and sex to the Danish background population without history of stroke (n = 858 740). Linking data to the Danish Cancer Registry, we determined prevalence of occult cancer in stroke defined as the event of previously unknown cancer during a 1-year follow-up in the stroke and in the background population. Cox regression models were used to study risk in comparison to the background population.

RESULTS

Prevalence (per 1000) of occult cancer in the stroke/background cohorts was 25.0/15.8 in women and 29.8/20.4 in men. Prevalence was dependent on age and sex. Highest among stroke patients aged 70-80 years (35.6 in women, 42.4 in men); lowest in patients aged 40-50 years (8.3 in women, 6.8 in men). Stroke was associated with an overall 54% higher risk of occult cancer but risk increased significantly with smoking, hazard ratio (HR) 1.47, age HR 1.27 per 10 years, male sex HR 1.25, and diabetes HR 1.25.

CONCLUSIONS

Prevalence and risk of occult cancer in stroke is considerable and calls for attention when designing the stroke investigation program.

Cancer-Related Stroke: An Emerging Subtype of Ischemic Stroke with Unique Pathomechanisms

Systemic cancer and ischemic stroke are common conditions and two of the most frequent causes of death among the elderly. The association between cancer and stroke has been reported worldwide. Stroke causes severe disability for cancer patients, while cancer increases the risk of stroke. Moreover, cancer-related stroke is expected to increase due to advances in cancer treatment and an aging population worldwide. Because cancer and stroke share risk factors (such as smoking and obesity) and treatment of cancer can increase the risk of stroke (e.g., accelerated atherosclerosis after radiation therapy), cancer may accelerate conventional stroke mechanisms (i.e., atherosclerosis, small vessel disease, and cardiac thrombus). In addition, active cancer and chemotherapy may enhance thrombin generation causing stroke related to coagulopathy. Patients with stroke due to cancer-related coagulopathy showed the characteristics findings of etiologic work ups, D-dimer levels, and infarct patterns. In this review, we summarized the frequency of cancer-related stroke among patients with ischemic stroke, mechanisms of stroke with in cancer patients, and evaluation and treatment of cancer-related stroke. We discussed the possibility of cancer-related stroke as a stroke subtype, and presented the most recent discoveries in the pathomechanisms and treatment of stroke due to cancer-related coagulopathy.

D-dimer and C-reactive Protein as Potential Biomarkers for Diagnosis of Trousseau's Syndrome in Patients with Cerebral Embolism

BACKGROUND

Differentiating stroke due to Trousseau's syndrome from other types of cerebral embolism is challenging, especially in patients with occult cancer. The current study aimed to determine predicting factors and biomarkers of stroke due to Trousseau's syndrome.

METHODS

This retrospective study comprised 496 consecutive patients with acute cerebral embolism, including 19, 85, 310, and, 82 patients with stroke due to Trousseau's syndrome, artery-to-artery embolism, cardioembolic stroke, and embolic stroke with undetermined source, respectively. All patients were evaluated within 72 hours of onset. The clinical characteristics, laboratory findings, and patterns on diffusion-weighted magnetic resonance imaging (DWI) were compared among the groups.

RESULTS

Plasma D-dimer and C-reactive protein (CRP) levels were significantly higher in the Trousseau's syndrome than in the other causes of cerebral embolism. Multivariate analyses demonstrated that female sex, multiple lesions on DWI, high D-dimer and CRP levels, and low platelet and low brain natriuretic peptide levels were independent predictors that could distinguish Trousseau's syndrome from the other causes of cerebral embolism. The cutoff values of D-dimer and CRP to identify stroke due to Trousseau's syndrome was 2.68 µg/mL fibrinogen equivalent units and .29 mg/dL, respectively.

CONCLUSIONS

The elevated D-dimer and CRP levels on admission in addition to specific clinical features may be useful for diagnosis of Trousseau's syndrome in patients with cerebral embolism.

Cancer-Related Ischemic Stroke Has a Distinct Blood mRNA Expression Profile

Background and Purpose- Comorbid cancer is common in patients with acute ischemic stroke (AIS). As blood mRNA profiles can distinguish AIS mechanisms, we hypothesized that cancer-related AIS would have a distinctive gene expression profile. Methods- We evaluated 4 groups of 10 subjects prospectively enrolled at 3 centers from 2009 to 2018. This included the group of interest with active solid tumor cancer and AIS and 3 control groups with active cancer only, AIS only, or vascular risk factors only. Subjects in the AIS-only and cancer-only groups were matched to subjects in the cancer-stroke group by age, sex, and cancer type (if applicable). Subjects in the vascular risk factor group were matched to subjects in the cancer-stroke and stroke-only groups by age, sex, and vascular risk factors. Blood was drawn 72 to 120 hours after stroke. Total RNA was processed using 3' mRNA sequencing. ANOVA and Fisher least significant difference contrast methods were used to estimate differential gene expression between groups. Results- In the cancer-stroke group, 50% of strokes were cryptogenic. All groups had differentially expressed genes that could distinguish among them. Comparing the cancer-stroke group to the stroke-only group and after accounting for cancer-only genes, 438 genes were differentially expressed, including upregulation of multiple genes/pathways implicated in autophagy signaling, immunity/inflammation, and gene regulation, including IL (interleukin)-1, interferon, relaxin, mammalian target of rapamycin signaling, SQSTMI1 (sequestosome-1), and CREB1 (cAMP response element binding protein-1). Conclusions- This study provides evidence for a distinctive molecular signature in blood mRNA expression profiles of patients with cancer-related AIS. Future studies should evaluate whether blood mRNA can predict detection of occult cancer in patients with AIS. Clinical Trial Registration- URL: https://clinicaltrials.gov. Unique identifier: NCT02604667.

Cancer Exacerbates Ischemic Brain Injury Via Nrp1 (Neuropilin 1)-Mediated Accumulation of Regulatory T Cells Within the Tumor

Background and Purpose- Adoptive transfer of regulatory T cells (Tregs) protect against stroke; however, Treg-based therapy raises concerns in stroke patients with cancer because of the immunosuppressive function of Tregs. The purpose of this study was to investigate the role of Tregs in cerebral ischemic brain injury with concomitant cancer. Methods- To establish a cancer phenotype, MC38 colon cancer or B16 melanoma cells (5×10⁵/mice) were injected subcutaneously into C57BL/6J mice 2 to 3 weeks before distal middle cerebral artery occlusion surgery. Infarct volume, neuroinflammation, and Tregs infiltration were measured by 2,3,5-triphenyltetrazolium chloride staining, immunofluorescence staining, real-time polymerase chain reaction, and flow cytometry. Mechanistically, Nrp1 (neuropilin-1) monoclonal antibody was used to block the Nrp1 effect on Tregs ex vivo before being transferred into recombination activating gene 1 (Rag1-/-) stroke mice, which are devoid of T and B cells, or a Nrp1 neutralization antibody was injected systemically into cancer-bearing wild-type mice after stroke. Results- Cancer-bearing mice with stroke exhibited augmented neuroinflammation and fewer Tregs in the brain, but more infiltration of Tregs to the tumor was apparent after distal middle cerebral artery occlusion. Depletion of Tregs increased infarct volume in stroke mice but did not further exacerbate brain injury in cancer-bearing stroke mice. Nrp1 blocking ex vivo or Nrp1 systemic neutralization attenuated ischemic brain injury and reversed accumulation of Tregs within tumor after stroke in cancer-bearing mice. Conclusions- Nrp1 signaling mediated accumulation of Tregs within tumor might play a critical role in exacerbating ischemic brain injury in cancer-bearing mice and may represent a promising immune modulatory target for the combined condition of cancer and stroke.

The emerging value of serum D-dimer measurement in the work-up and management of ischemic stroke

Background

Elevated D-dimer levels are a marker of both thrombin formation and fibrinolysis. Currently D-dimer measurement is routinely used for ruling out venous thromboembolism and diagnosis/monitoring of disseminated intravascular coagulation. Recent emerging data suggest that D-dimer may become an important biomarker in ischemic stroke as well as in cardiovascular diseases.

Aims

To outline the clinical utility of D-dimer in work-up and management of ischemic stroke.

Summary

D-dimer measurement is most useful in stroke with active cancer as it can confirm etiologic diagnosis, predict recurrent stroke risk, and aid treatment decision in cancer-associated stroke. In cryptogenic stroke, high D-dimer levels can also provide clues for the cause of stroke as occult cancer and undetected cardiac embolic source as occult atrial fibrillation and may be helpful in treatment decision making of secondary stroke prevention. Serial D-dimer measurements should be further studied to monitor antithrombotic therapy effectiveness in both cardiogenic and cryptogenic etiologies.

Conclusion

Accumulating data suggests the utility of D-dimer test in the management of ischemic stroke, although the evidence is still limited. Future studies would clarify the role of D-dimer measurement in ischemic stroke.

Increased risk for cancer after stroke at a young age: etiological relevance or incidental finding?

BACKGROUND

Etiological factors, such as a malignant disease, in young stroke patients are often neglected. Therefore, in this study, we aimed to investigate the risk of developing cancer in young stroke survivors.

METHODS

The current case-control study sample included patients who received an initial ischemic stroke diagnosis documented in the Disease Analyzer database (IQVIA), which compiles data such as risk factors, drug prescriptions, and diagnoses obtained from general practitioners and specialists.

RESULTS

The stroke and non-stroke groups included 18,668 patients each; each group had 2836 (15.3%) participants ≤ 55 years. The cancer incidence in the stroke group over the age of 55 years was higher than in the younger subgroup (29.4% versus 17.3%). The proportions of cancer patients within 10 years of follow-up were higher in the stroke group versus the non-stroke group, as well as in the subgroup of patients aged ≤ 55 versus patients > 55 years (17.3% versus 9.5% and 29.4% versus 24.9%, respectively). The calculated hazard ratio for developing cancer within 10 years of follow-up was higher in the younger stroke population (≤ 55 years) than in the older population (hazard ratio: 1.47 (CI 1.18-1.83) versus 1.17 (CI 1.10-1.25).

CONCLUSION

In our cohort, young individuals aged ≤ 55 years who suffered a stroke had twice as high risk for developing cancer within 10 years after the index event compared to the control group. Stroke might have implication regarding the subsequent development of cancer and vice versa.

Specific Biomarkers of Prostate Cancer-Associated Ischemic Stroke: A Case-Control Study

Background

Ischemic stroke in cancer patients is associated with poor prognosis. However, the specific biomarkers of cancer-associated ischemic stroke (CaIS) have not been well defined.

Material/Methods

A retrospective study was conducted on PCaIS patients. Clinical data and laboratory and imaging findings were collected. Multivariable logistic regression analysis was used to analyze the independent risk factors for PCaIS. A multiple model combining the independent risk factors of PCaIS was developed using the receiver operating characteristic (ROC) and area under the ROC curve (AUC).

Results

A total of 83 PCaIS patients and 83 prostate cancer (PCa) patients were included. PCaIS patients had higher levels of D-dimer, neutrophil-to-lymphocyte ratio (NLR), and total prostate-specific antigen (T-PSA). In the multivariate analysis, D-dimer [OR=1.001, 95% CI: 1.00,1.00, P=0.002], NLR [OR=1.12, 95% CI: 1.04,1.22, P=0.005], and T-PSA [OR=6.275, 95% CI: 2.57,15.31, P<0.001] were independent risk factors of PCaIS. Additionally, the AUC of the multiple model of PCaIS was 0.815 (95% CI, 0.750–0.869), with sensitivity of 81.71% and specificity of 70.21%.

Conclusions

Elevated levels of D-dimer and T-PSA and increased NLR are independent risk factors of PCaIS. The multiple model of PCaIS can be a specific biomarker and is a reliable predictor of development of PCaIS.

Cancer-associated stroke: Pathophysiology, detection and management (Review)

Numerous types of cancer have been shown to be associated with either ischemic or hemorrhagic stroke. In this review, the epidemiology and pathophysiology of stroke in cancer patients is discussed, while providing vital information on the diagnosis and management of patients with cancer and stroke. Cancer may mediate stroke pathophysiology either directly or via coagulation disorders that establish a state of hypercoagulation, as well as via infections. Cancer treatment options, such as chemotherapy, radiotherapy and surgery have all been shown to aggravate the risk of stroke as well. The clinical manifestation varies greatly depending upon the underlying cause; however, in general, cancer‑associated strokes tend to appear as multifocal in neuroimaging. Furthermore, several serum markers have been identified, such as high D‑Dimer levels and fibrin degradation products. Managing cancer patients with stroke is a delicate matter. The cancer should not be considered a contraindication in applying thrombolysis and recombinant tissue plasminogen activator (rTPA) administration, since the risk of hemorrhage in cancer patients has not been reported to be higher than that in the general population. Anticoagulation, on the contrary, should be carefully examined. Clinicians should weigh the benefits and risks of anticoagulation treatment for each patient individually; the new oral anticoagulants appear promising; however, low‑molecular‑weight heparin remains the first choice. On the whole, stroke is a serious and not a rare complication of malignancy. Clinicians should be adequately trained to handle these patients efficiently.

Cancer risk in stroke survivors followed for up to 10 years in general practices in Germany

AIMS

The goal of this study was to analyze cancer risk in stroke survivors followed for up to 10 years in general practices in Germany.

METHODS

The current study sample included patients who received an initial stroke diagnosis in one of 1262 general practices in Germany between 2006 and 2015 (index date). Patients without stroke were matched (1:1) to patients with stroke by age, gender, index year, and 16 comorbidities diagnosed in the 12 months prior to the index date using a propensity score method. The main outcome of the study was the risk of cancer as a function of stroke within 10 years of the index date.

RESULTS

The stroke and non-stroke groups included 9579 men and 9089 women. After 10 years of follow-up, 29.3% of men with stroke and 23.8% of those without stroke developed any of the included types of cancer (log-rank p value < 0.001). During the same time, the prevalence of cancer was 25.0% in women with stroke and 20.5% in women without stroke (log-rank p value < 0.001). There was a positive association between stroke and any cancer in men (hazard ratio [HR] = 1.18, 95% confidence interval [CI] 1.09-1.28) and in women (HR = 1.22, 95% CI 1.12-1.34). This association was significant for cancers of respiratory and intrathoracic organs in men and women and for cancers of digestive organs in men.

CONCLUSIONS

This study, including more than 37,000 patients from Germany, found that stroke was associated with an increased cancer risk.

Ischemic stroke in cancer patients: A review of an underappreciated pathology

Currently 1 in 10 patients with ischemic stroke have comorbid cancer, and this frequency is expected to increase with continued advances in cancer therapeutics prolonging median survival. Well known for its association with venous thrombosis, cancer has recently emerged as a significant risk factor for arterial thromboembolism, including stroke; however, the underlying mechanisms are uncertain. In addition, the optimal strategies to prevent and acutely treat stroke in cancer patients are yet to be established. This review summarizes the current evidence on ischemic stroke risk, biomarkers, pathophysiology, treatments, and prognosis in cancer patients, emphasizing knowledge gaps and the potential strategies to address them. Ann Neurol 2018;83:873-883.

When to Screen Ischaemic Stroke Patients for Cancer

BACKGROUND AND PURPOSE

Ischemic stroke can be the first manifestation of cancer and it is therefore important to ascertain which stroke patients should be considered for cancer-diagnostic investigations. We aimed to determine the frequency of active cancer in patients with acute ischemic stroke and to compare clinical findings in stroke patients with active cancer to ischemic stroke patients with no history of cancer. Finally, we aimed to develop a predictive and feasible score for clinical use to uncover underlying malignancy.

METHODS

All ischemic stroke patients admitted to the stroke unit in the Department of Neurology, Haukeland University Hospital were consecutively included in the Norwegian Stroke Research Registry (NORSTROKE). Stroke etiology was determined by the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. Data on cancer diagnoses was obtained from patients' medical records and the Cancer Registry of Norway. Active cancer was defined as cancer diagnosis, metastasis of known cancer, recurrent cancer or receiving cancer treatment, all within 12 months before or after the index stroke. Based on variables independently associated with active cancer, a predictive score was developed using the area under the receiver operating characteristic (AUC-ROC) curves. Bayes' theorem was used to calculate post-test probabilities of active cancer.

RESULTS

Of the 1,646 ischemic stroke patients included, 82 (5.0%) had active cancer. Increased D-dimer (OR = 1.1, 95% CI: 1.1-1.2, p = <0.001), lower Hb (OR = 0.6, 95% CI: 0.5-0.7, p = <0.001), smoking (OR = 2.2, 95% CI: 1.2-4.3, p = 0.02) and suffering a stroke of undetermined etiology (OR = 1.9, 95% CI: 1.1-3.3, p = 0.03) were factors independently associated with active cancer. These were included in the final predictive score which gave an AUC of 0.73 (95% CI: 0.65-0.81) in patients younger than 75 years of age. Assuming the prevalence of cancer to be 5%, the score shows that if a patient fulfills all 3 score points, the probability of active cancer is 53%.

CONCLUSIONS

Active cancer was found in 5% of our ischemic stroke patients. We found that a clinical score comprising elevated D-dimer ≥3 mg/L, lower Hb ≤12.0 g/dL and previous or current smoking is feasible for predicting active cancer in ischemic stroke patients.