Cryptogenic subtype predicts reduced survival among cancer patients with ischemic stroke

Cryptogenic Stroke: Research and Practice

BACKGROUND

Cryptogenic stroke accounts for 30% to 40% of ischemic stroke. It is essential to determine the possible culprit because this will improve secondary stroke prevention strategies.

METHODS

We performed a narrative nonsystematic review of the literature that included randomized trials, exploratory comparative studies, and case series on cryptogenic stroke.

RESULTS

There are several possible mechanisms implicated in cryptogenic stroke, including occult paroxysmal atrial fibrillation, patent foramen ovale, aortic arch atherosclerosis, atrial cardiopathy, and substenotic atherosclerosis. The heterogeneity of these mechanisms leads to differences in stroke prevention strategies among cryptogenic stroke patients.

CONCLUSIONS

A thorough diagnostic evaluation is essential to determine the pathogenesis in cryptogenic stroke. This approach, in addition to risk factor management and lifestyle modifications, will lead to improved stroke prevention strategies in patients with cryptogenic stroke. This will allow for targeted clinical trials to improve stroke prevention strategies in this patient population.

Imaging characteristics associated with clinical outcomes in posterior reversible encephalopathy syndrome

PURPOSE

Posterior reversible encephalopathy syndrome (PRES) is a disorder of cerebrovascular autoregulation that can result in brain edema, hemorrhage, and infarction. We sought to investigate whether certain imaging characteristics in PRES are associated with clinically significant patient outcomes.

METHODS

We retrospectively reviewed all cases of PRES occurring between 2008 and 2014 at two major academic medical centers. Demographic, clinical, and radiographic data were collected. We analyzed imaging studies for vasogenic edema, hemorrhage, and diffusion restriction. We performed univariate analysis and stepwise logistic regression to assess the association between our radiologic findings of interest and clinical outcomes as defined by hospital discharge disposition and modified Rankin scale (mRS) at time of discharge.

RESULTS

We identified 99 cases of PRES in 96 patients. The median age was 55 years (IQR 30-65) and 74% were women. In 99 cases, 60% of patients had active cancer, 19% had history of bone marrow or organ transplantation, 14% had autoimmune disease, and 8% were peripartum. Imaging at clinical presentation showed extensive vasogenic edema in 39%, hemorrhage in 36%, hemorrhage with mass effect in 7%, and restricted diffusion in 16%. In our final logistic regression models, the presence of extensive vasogenic edema, hemorrhage with mass effect, or diffusion restriction was associated with worse clinical outcome as defined by both discharge disposition (OR = 4.3; 95% CI: 1.4-36.3; p = 0.047) and mRS (OR = 3.6; 95% CI: 1.2-10.7; p = 0.019).

CONCLUSIONS

Extensive vasogenic edema, hemorrhage, and restricted diffusion on initial imaging in PRES are associated with worse clinical outcomes.

Vascular complications in glioma patients

Vascular complications in patients with glioma most commonly include venous and arterial thromboembolism; however, treatment-induced vasculopathies are also problematic, especially in long-term survivors. The interactions between treatment such as radiation and chemotherapy, the coagulation cascade, endothelium, and regulators of angiogenesis are complex, drive glioma growth and invasion, and create common management problems in the clinic. We review the incidence of thrombotic complications in glioma, the biology of the coagulome as related to glioma progression, prevention and treatment of thrombosis, the role of anticoagulants as anticancer therapy, and vascular complications such as ischemic stroke and intracranial bleeding. The coagulation cascade is intimately involved in cancer-related thrombosis, glioma progression, and vascular complications of glioma therapy. Tissue factor is the principal initiator of coagulation and is upregulated in a glioma subtype-specific fashion. Short-term (perioperative) antithrombotic prophylaxis is effective, but long-term anticoagulation, although attractive, is not routinely indicated. Most patients with symptomatic venous thromboembolism can be safely anticoagulated, including those on anti-vascular endothelial growth factor therapeutics such as bevacizumab. Initial therapy should include low-molecular-weight heparin, and protracted anticoagulant treatment, perhaps indefinitely, is indicated. Many complex interactions resulting in vessel wall injury can lead to ischemic stroke, intracranial and intratumoral hemorrhage, and long-term sequelae such as cognitive impairment.

Hypercoagulability and Mortality of Patients with Stroke and Active Cancer: The OASIS-CANCER Study

Background and Purpose

Patients with active cancer are at an increased risk for stroke. Hypercoagulability plays an important role in cancer-related stroke. We aimed to test whether 1) hypercoagulability is a predictor of survival, and 2) correction of the hypercoagulable state leads to better survival in patients with stroke and active cancer.

Methods

We recruited consecutive patients with acute ischemic stroke and active systemic cancer between January 2006 and July 2015. Hypercoagulability was assessed using plasma D-dimer levels before and after 7 days of anticoagulation treatment. The study outcomes included overall and 1-year survival. Plasma D-dimer levels before and after treatment were tested in univariate and multivariate Cox regression models. We controlled for systemic metastasis, stroke mechanism, age, stroke severity, primary cancer type, histology, and atrial fibrillation using the forward stepwise method.

Results

A total of 268 patients were included in the analysis. Patients with high (3rd–4th quartiles) pre-treatment plasma D-dimer levels showed decreased overall and 1-year survival (adjusted HR, 2.19 [95% CI, 1.46–3.31] and 2.70 [1.68–4.35], respectively). After anticoagulation treatment, post-treatment D-dimer level was significantly reduced and independently associated with poor 1-year survival (adjusted HR, 1.03 [95% CI, 1.01–1.05] per 1 μg/mL increase, P=0.015). The successful correction of hypercoagulability was a protective factor for 1-year survival (adjusted HR 0.26 [CI 0.10–0.68], P=0.006).

Conclusions

Hypercoagulability is associated with poor survival after stroke in patients with active cancer. Effective correction of hypercoagulability may play a protective role for survival in these patients.

Multiple Infarcts Are Associated With Long-Term Stroke Recurrence and All-Cause Mortality in Cryptogenic Stroke Patients

Background and Purpose—

Brain infarct patterns that are observed via diffusion-weighted imaging are useful for classifying stroke subtypes. However, it is unclear whether infarct patterns can predict long-term outcomes in cryptogenic stroke patients. Herein, we investigated the association between acute brain infarct patterns and long-term stroke outcomes in cryptogenic stroke patients.

Methods—

Acute cryptogenic stroke patients were consecutively enrolled between April 2008 and March 2012. Diffusion-weighted imaging ischemic lesion patterns were classified as single lesions, scattered lesions in one vascular territory, or multiple lesions in multiple vascular territories. Survivors (at discharge) were followed up for 3 years after stroke onset.

Results—

A total of 272 cryptogenic stroke patients (132 women; aged 72±13 years) were enrolled. Among these patients, 169 (62.1%) had a single lesion, 38 (14.0%) had scattered lesions, and 65 (23.9%) had multiple lesions. Next, 261 patients (96.0%) were evaluated to assess right-to-left shunting, and 61 patients (23.4%) exhibited right-to-left shunting. On patient admission, right-to-left shunting and increased D-dimer levels were independently associated with multiple lesions but not single or scattered lesions. During the follow-up period (median, 1093 days), 30 patients (11.0%) developed recurrent stroke and 35 patients (12.9%) died. Multivariate Cox proportional hazard analyses showed that multiple infarcts were independently associated with recurrent stroke and all-cause mortality (hazard ratio, 3.79; 95% confidence interval, 2.24–6.37; P <0.001).

Conclusions—

Multiple brain infarcts on diffusion-weighted imaging were independently associated with long-term stroke outcomes in cryptogenic stroke patients.

Predictors of survival for patients with cancer after cryptogenic stroke

Patients with active cancer experience ischemic stroke via cryptogenic mechanisms, with cancer-associated hypercoagulability being considered a major contributor to such strokes. Despite the remarkably shortened survival of these patients, the clinical predictors of survival are poorly understood. We determined the clinical factors including D-dimer levels serving as the predictors of overall survival in these patients. Retrospective study was conducted on cancer patients who visited our hospital for acute ischemic stroke with cryptogenic mechanisms from April 2012 through November 2014. Demographics, clinical characteristics, imaging and laboratory results including coagulation markers were collected, and overall survival was calculated from the patient medical records and a governmental national database. A high D-dimer level was defined as a D-dimer level exceeding the median value from the study population (>5.50 μg/ml). A total of 93 patients were identified, with a median survival of 62 days (interquartile range 32-223 days). A high D-dimer level (p = 0.004; hazard ratio [HR] 2.01, 95 % confidence interval [CI] 1.26-3.21), systemic metastases (p = 0.02; HR 2.08, 95 % CI 1.11-3.90), and diabetes mellitus (p = 0.03; HR 1.78, 95 % CI 1.03-3.10) were identified as independent predictors of poor overall survival using multivariate Cox proportional hazard analysis. Most of the patients (87 %) were primarily treated with low-molecular-weight heparin (dalteparin, n = 49; enoxaparin, n = 32). The type of low-molecular-weight heparin had no association with survival. A high D-dimer level, systemic metastases, and diabetes are independent predictors of poor survival in cancer patients with cryptogenic stroke.

Characteristics of cryptogenic stroke in cancer patients

Objective

To clarify the characteristics of cryptogenic stroke in patients with active cancer.

Methods

Patients with or without cancer diagnosed with acute ischemic stroke between January 2006 and February 2015 were extracted from a prospectively collected stroke database of Osaka University Hospital. Patients were categorized according to the presence of active cancer and known stroke mechanisms.

Results

Among 1191 patients with acute ischemic stroke, 145 (12%) had active cancer. Patients with active cancer were diagnosed more often with cryptogenic stroke than were patients without cancer (47% vs. 12%, P < 0.001). Compared with cryptogenic stroke patients without cancer, cryptogenic stroke patients with active cancer had fewer atherosclerotic risk factors, lower nutrition status, higher plasma D‐dimer levels, and multiple vascular lesions. In a multivariate logistic analysis, plasma D‐dimer level (odds ratio [OR] per 1 standard deviation increase: 6.30; 95% confidence interval [CI]: 2.94–15.69; P < 0.001), and the presence of multiple vascular lesions (OR: 6.40; 95% CI: 2.35–18.35; P < 0.001) were independent predictors of active cancer. When comparing active cancer patients who had known stroke mechanisms with those who had cryptogenic stroke, high plasma D‐dimer levels, multiple vascular lesions, and receiving chemotherapy and/or radiation therapy were associated with cryptogenic stroke etiology.

Interpretation

In cryptogenic stroke, patients with active cancer has a unique pathology characterized by high plasma D‐dimer levels and multiple vascular lesions. The hypercoagulable state and malnutrition due to cancer and its treatments potentially influence the development of cryptogenic stroke in cancer patients.

Thrombomodulin and High-Sensitive C-Reactive Protein Levels in Blood Correlate with the Development of Cerebral Infarction Among Asians

Our meta-analysis was designed to obtain the correlation between thrombomodulin (TM) and high-sensitive C-reactive protein (hs-CRP) levels and the development of cerebral infarction (CI). Case-control studies relevant to the role plasma TM levels and serum hs-CRP levels in the development of CI were retrieved both electronically and manually and further screened according to a predetermined inclusion and exclusion criteria. All enrolled studies were analyzed for meta-regression analyses, sensitivity analyses, and assessments of publication bias. Comprehensive Meta-analysis 2.0 software (CMA 2.0) was used for statistical analysis. A total of 359 studies were initially retrieved, and 13 studies were eventually recruited into our meta-analysis with a total of 881 CI patients (plasma TM levels: n = 513; serum hs-CRP levels: n = 368) and 1067 healthy controls. The results of our meta-analysis suggested that plasma TM levels and serum hs-CRP levels in CI patients were significantly higher than those in healthy controls. In conclusion, increased plasma TM levels and serum hs-CRP levels in CI patients were associated with the development of CI in Asians.

Diagnostic yield of echocardiography in cancer patients with ischemic stroke

The yield of echocardiography in cancer patients with acute ischemic stroke is unknown. We identified adult patients with active systemic cancer diagnosed with acute ischemic stroke at a tertiary-care cancer center from 2005 through 2009 who underwent transthoracic (TTE) or transesophageal echocardiography (TEE). Two neurologists independently reviewed all clinical data, including TTE and TEE reports, and adjudicated whether echocardiographic studies revealed a definite or possible source of stroke according to pre-defined criteria. Patients were classified as having suspected cardioembolic strokes if imaging showed embolic-appearing infarcts in more than one vascular territory. Among 220 patients with cancer and ischemic stroke who underwent echocardiography, 216 (98%) had TTE and 37 (17%) had TEE. TTE revealed a definite source in 15 (7%, 95% CI 4-10%) patients and a possible source in 42 (19%, 95% CI 14-25%), while TEE revealed a definite source in 10 (27%, 95% CI 12-42%) patients and a possible source in 14 (38%, 95% CI 21-54%). In 92 patients with suspected cardioembolic strokes who underwent TTE, 6 (7%, 95% CI 1-12%) had a definite source, including 4 with marantic endocarditis, and 20 (22%, 95% CI 13-30%) had a possible source. Twenty-one of these patients also underwent TEE, which demonstrated a definite or possible source in 16 (76%, 95% CI 56-96%) patients, including marantic endocarditis in 4 (19%). The yield of TTE for detecting marantic endocarditis and other cardiac sources of stroke in cancer patients is low, but TEE may provide a higher yield in targeted patients.