Major cerebral infarction from tumor embolus

Epidemiology, Pathophysiology, and Management of Cancer-Associated Ischemic Stroke

Cancer and stroke are leading causes of global disability and mortality. With improvements in cancer-associated mortality and advancements in treatment of active malignancy, it is more common to encounter patients with ischemic stroke and active malignancy. Evidence suggests that cancer-associated ischemic stroke is a unique subtype of stroke; however, there is limited guidance when considering diagnostic workup, secondary prevention, rehabilitation, and future directions within this population. In this narrative review, we aim to describe the epidemiology, pathophysiological mechanisms, management, and future directions regarding understanding of cancer-associated ischemic stroke.

Decoding the Nexus: Cellular and Molecular Mechanisms Linking Stroke and Neurotoxic Microenvironments in Brain Cancer Patients

Stroke is an often underrecognized albeit significant complication in patients with brain cancer, arising from the intricate interplay between cancer biology and cerebrovascular health. This review delves into the multifactorial pathophysiological framework linking brain cancer to elevated stroke risk, with particular emphasis on the crucial role of the neurotoxic microenvironment (NTME). The NTME, characterized by oxidative stress, neuroinflammation, and blood-brain barrier (BBB) disruption, creates a milieu that promotes and sustains vascular and neuronal injury. Key pathogenic factors driving brain cancer-related stroke include cancer-related hypercoagulability, inflammatory and immunological mechanisms, and other tumor-associated processes, including direct tumor compression, infection-related sequelae, and treatment-related complications. Recent advances in genomic and proteomic profiling present promising opportunities for personalized medicine, enabling the identification of biomarkers-such as oncogenes and tumor suppressor genes-that predict stroke susceptibility and inform individualized therapeutic strategies. Targeting the NTME through antioxidants to alleviate oxidative stress, anti-inflammatory agents to mitigate neuroinflammation, and therapies aimed at reinforcing the BBB could pave the way for more effective stroke prevention and management strategies. This integrative approach holds the potential to reduce both the incidence and severity of stroke, ultimately improving clinical outcomes and quality of life for brain cancer patients. Further research and well-designed clinical trials are essential to validate these strategies and integrate them into routine clinical practice, thereby redefining the management of stroke risk in brain cancer patients.

Systematic review and meta-analysis of studies comparing baseline D-dimer level in stroke patients with or without cancer: Strength of current evidence

Objectives

D-dimer levels are increased in stroke and cancer. Cancer patients are at a higher risk of stroke. However, the evidence is unclear if high D-dimer in stroke patients can suggest the diagnosis of concomitant cancer or the development of stroke in a cancer patient. The objective is to assess the evidence available on the baseline D-dimer level in stroke patients with and without cancer.

Materials and Methods

We conducted the systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched PUBMED, Cochrane, ScienceDirect, and Scopus for potentially eligible articles published till June 2023. All the review steps were iterative and done independently by two reviewers. The Newcastle-Ottawa scale tool was used to assess the quality of included studies for case control and cohort studies and the Agency for Healthcare Research and Quality tool for cross-sectional studies. The qualitative synthesis is presented narratively, and quantitative synthesis is shown in the forest plot using the random effects model. I2 of more than 60% was considered as high heterogeneity.

Results

The searches from all the databases yielded 495 articles. After the study selection process, six papers were found eligible for inclusion in the qualitative and quantitative synthesis. In the present systematic review, 2651 patients with ischemic infarcts are included of which 404 (13.97%) patients had active cancer while 2247 (86.02%) did not. The studies included were of high quality and low risk of bias. There were significantly higher baseline D-dimer levels in stroke patients with cancer than in non-cancer patients with a mean difference of 4.84 (3.07-6.60) P < 0.00001.

Conclusion

D-dimer is a simple and relatively non-expensive biomarker that is increased to significant levels in stroke patients, who have cancer and therefore may be a tool to predict through screening for active or occult cancer in stroke patients.

Clinical Features and Prognostic Factors of Acute Ischemic Stroke Related to Malignant Gastrointestinal Tumor

Objectives: To analyze the clinical and imaging features of acute ischemic stroke (AIS) related to gastrointestinal malignant tumor, and to explore the prognostic factors.

Methods: Clinical data of consecutive patients with gastrointestinal malignant tumor complicated with AIS admitted to the Department of Neurology and Oncology in Lanzhou University Second Hospital from April 2015 to April 2019 were retrospectively analyzed. Patients were divided into good prognosis (mRS 0–2) and poor prognosis (mRS > 2) based on a 90-day mRS score after discharge. The multivariate logistic regression model was used to analyze the prognostic factors.

Results: A total of 68 patients were enrolled with an average age of 61.78 ± 6.65 years, including 49 men (72.06%). There were 18 patients in the good prognosis group and 50 patients in the poor prognosis group. The univariate analysis showed that Hcy, D-dimer, thrombin–antithrombin complex (TAT), and three territory sign in magnetic resonance imaging (MRI) were the risk factors for poor prognosis. Multivariate analysis showed that increased D-dimer (OR 4.497, 95% CI 1.014–19.938) and TAT levels (OR 4.294, 95% CI 1.654–11.149) were independent risk factors for the prognosis in such patients.

Conclusion: Image of patients with gastrointestinal malignant tumor-related AIS is characterized by three territory sign (multiple lesions in different vascular supply areas). Increased TAT and D-dimer levels are independent prognostic risk factors. TAT is more sensitive to predict prognosis than D-dimer.

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.

Neoplastic embolization to systemic and pulmonary arteries

OBJECTIVE

Arterial neoplastic emboli are uncommon, accounting for <1% of thromboemboli in the current literature. Nonetheless, this event may be associated with significant morbidity and mortality. Herein, we report a series of 11 cases of arterial neoplastic emboli from a single tertiary care center along with a comprehensive review of the literature to date. The aim of this study was to document the incidence, clinical presentations, and complications of arterial neoplastic emboli as well as to highlight the importance of routine histologic examination of thrombectomy specimens.

METHODS

Pathology archives from a single tertiary care institution were queried to identify cases of surgically resected arterial emboli containing neoplasm (1998-2014). Histopathology was reviewed for confirmation of diagnosis. Patient demographics and oncologic history were abstracted from the medical record. Comprehensive literature review documented 332 patients in 275 reports (1930-2016).

RESULTS

Eleven patients (six men) with a median age of 63 years (interquartile range, 42-71 years) were identified through institutional archives. Embolism was the primary form of diagnosis in seven (64%) cases. Cardiac involvement (primary or metastasis) was present in more than half of the cohort. Comprehensive literature review revealed that pulmonary primaries were the most common anatomic origin of arterial neoplastic emboli, followed by gastrointestinal neoplasia. Cardiac involvement was present in 18% of patients, and sentinel identification of neoplasia occurred in 30% of cases. Postmortem evaluation was the primary means of diagnosis in 27%.

CONCLUSIONS

This study highlights the importance of routine histopathologic evaluation of embolectomy specimens in patients with and without documented neoplasia.

D-dimer levels and cerebral infarction in critically ill cancer patients

BACKGROUND

D-dimer levels have been used in the diagnosis of a variety of thrombosis-related diseases. In this study, we evaluated whether measuring D-dimer levels can help to diagnose cerebral infarction (CI) in critically ill cancer patients.

METHODS

We retrospectively evaluated all cancer patients who underwent brain magnetic resonance imaging (MRI) between March 2010 and February 2014 at the medical oncology intensive care unit (ICU) of Samsung Medical Center. Brain MRI scanning was performed when CI was suspected due to acute neurological deficits. We compared D-dimer levels between patients ultimately diagnosed as having or not having CI and analyzed diffusion-weighted imaging (DWI) lesion patterns.

RESULTS

A total of 88 patients underwent brain MRI scanning due to clinical suspicion of CI; altered mental status and unilateral hemiparesis were the most common neurological deficits. CI was ultimately diagnosed in 43 (49%) patients. According to the DWI patterns, multiple arterial infarctions (40%) were more common than single arterial infarctions (9%). Cryptogenic stroke etiologies were more common (63%) than determined etiologies. There was no significant difference in D-dimer levels between patients with and without CI (P = 0.319). Although D-dimer levels were not helpful in diagnosing CI, D-dimer levels were associated with cryptogenic etiologies in critically ill cancer patients; D-dimer levels were higher in the cryptogenic etiology group than in the determined etiology group or the non-infarction group (P = 0.001). In multivariate analysis, elevated D-dimer levels (> 8.89 μg/mL) were only associated with cryptogenic stroke (adjusted OR 5.46; 95% confidence interval, 1.876-15.857).

CONCLUSIONS

Abnormal D-dimer levels may support the diagnosis of cryptogenic stroke in critically ill cancer patients.

Stroke Caused by Lung Cancer Invading the Left Atrium

We describe a 59-year-old stroke patient presented with sudden onset left side weakness and a speech disorder due to a major acute cerebral infarction in the area of the right middle cerebral artery, right posterior cerebral artery, and small infarctions in the area of the left middle and left posterior cerebral artery. For the previous month, the patient had been feeling weak and had no appetite. The patient had not been previously seriously ill. A chest x-ray showed a large mass in the upper zone of the right lung. Chest computed tomography scan and echocardiography were performed and revealed advanced lung cancer invading the left atrium. Spontaneous tumor embolism is a rare cause of stroke and should be considered in the differential diagnosis of stroke in a cancer patient. Also, sometimes stroke can be the first manifestation of advanced cancer.

Ischemic Stroke in Critically Ill Patients with Malignancy

Background

Cerebrovascular diseases are a frequent cause of neurological symptoms in patients with cancer. The clinical characteristics of ischemic stroke (IS) in patients with cancer have been reported in several studies; however, limited data are available regarding critically ill patients with cancer who develop IS during their stay in the intensive care unit (ICU).

Methods

All consecutive patients who underwent brain magnetic resonance imaging (MRI) for suspicion of IS with acute abnormal neurologic symptoms or who developed signs of IS while in the ICU were retrospectively evaluated. We compared the clinical characteristics and diffusion-weighted imaging (DWI) lesion patterns between patients finally diagnosed as having or not having IS.

Results

Over the study period, a total of 88 patients underwent brain MRI for suspicion of IS, with altered mental status in 55 (63%), hemiparesis in 28 (32%), and seizure in 20 (23%). A total of 43 (49%) patients were ultimately diagnosed with IS. Multiple DWI lesions (41%) were more common than single lesions (8%). The etiologies of IS were not determined in the majority of patients (n = 27, 63%). In the remaining 16 (37%) patients, the most common aetiology of IS was cardioembolism (n = 8), followed by large-vessel atherosclerosis (n = 3) and small-vessel occlusion (n = 2). However, brain metastases were newly diagnosed in only 7 (8%) patients. Univariate comparison of the baseline characteristics between patients with or without IS did not reveal any significant differences in sex, malignancy type, recent chemotherapy, vascular risk factors, or serum D-dimer levels at the time of suspicion of IS. Thrombotic events were more common in the IS group than in the non-IS group (P = 0.028). However, patients who were ultimately diagnosed with IS had more hemiparesis symptoms at the time of suspicion of IS (P = 0.001). This association was significant even after adjusting for potentially confounding factors (adjusted odds ratio 5.339; 95% confidence interval, 1.521–19.163).

Conclusions

IS developed during ICU stays in critically ill patients with cancer have particular features that may be associated with cancer-related mechanism.

Neurologic complications of cardiac tumors

Cardiac tumors are an uncommon cause for neurologic disease, but if undiagnosed can be associated with devastating neurologic consequences. Primary cardiac tumors, both benign and neoplastic, and metastatic tumors occur. Primary cardiac tumors are more likely to be associated with neurologic embolic complications. Metastatic cardiac tumors are more likely to be associated with valvular distraction, arrhythmia, diminished cardiac output and indirect neurological dysfunction. Primary and metastatic cardiac tumors may result in cerebral metastatic disease. Atrial myxoma, a benign primary cardiac tumor, is the most common cardiac tumor associated with neurologic disease, and most commonly causes cerebral embolization and stroke. The use of thrombolytic therapy for these strokes is controversial. Additionally, delayed manifestations, including aneurysm formation and intracranial hemorrhage, are possible. Aneurysm formation has been described as occurring after removal of the primary tumor. The availability of noninvasive cardiac imaging has significantly helped decrease the neurologic morbidity of cardiac tumors and has led to frequent successful intervention.

Lesions masquerading as acute stroke

Rapid and accurate recognition of lesions masquerading as acute stroke is important. Any incorrect or delayed diagnosis of stroke mimics will not only increase the risk of being exposed to unnecessary and possibly dangerous interventional therapies, but will also delay proper treatment. In this article, written from a neuroradiologist's perspective, we classified these lesions masquerading as acute stroke into three groups: lesions that may have "normal imaging," lesions that are "symptom mimics" but on imaging clearly not a stroke, and lesions that are "symptom and imaging mimics" with imaging findings similar to stroke. We focused the review on neuroimaging findings of the latter two groups ending with a suggestion for a diagnostic approach in the form of an algorithm.

Cerebral edema, altered mental status, seizures, acute stroke, leptomeningeal metastases, and paraneoplastic syndrome

Neurologic symptoms commonly occur in oncology patients, and in some cases they may be the presenting symptom of malignancy. Cancer-related neurologic syndromes are rarely pathognomonic and must be differentiated from other benign or serious conditions. This article reviews common neuro-oncologic syndromes that may lead to urgent evaluation in the emergency department, including cerebral edema, altered mental status, seizures, acute stroke, leptomeningeal metastases, and paraneoplastic neurologic syndromes.

Stroke and cancer: a review

Stroke is a disabling disease and can add to the burden of patients already suffering from cancer. Several major mechanisms of stroke exist in cancer patients, which can be directly tumour related, because of coagulation disorders, infections, and therapy related. Stroke can also occur as the first sign of cancer, or lead to its detection. The classical literature suggests that stroke occurs more frequently in cancer patients than in the average population. More recent studies report a very similar incidence between cancer and non-cancer patients. However, there are several cancer-specific types and causes of stroke in cancer patients, which need to be considered in each patient. This review classifies stroke into ischaemic, haemorrhagic, cerebral venous thrombosis and other rarer types of cerebrovascular disease. Its aim is to identify the types of stroke most frequently associated with cancer, and give a practical view on the most common and most specific types of stroke. The diagnosis of the cause of stroke in cancer patients is crucial for treatment and prevention. Management of different stroke types will be briefly discussed.

Intracranial metastasis from synovial sarcoma

Synovial sarcomas comprise between 5% to 10% of all soft tissue sarcomas in adults. It has a predilection for young adults and is one of the more frequently misdiagnosed soft tissue sarcomas. It is not unusual for synovial sarcoma to present initially after a traumatic event. It most commonly occurs in close proximity to a large joint. The most common site for metastasis is the lung, followed by lymph node involvement. Synovial sarcoma rarely metastasizes to the skeleton and when it occurs, it most commonly involves the long bones. Cranial metastasis is rare and has only been described in 2 previously reported cases. Reports of other sarcomas having intracranial metastasis include rhabdomyosarcoma, angiosarcoma, fibrosarcoma, liposarcoma, Ewing's sarcoma, and clear cell sarcoma from the kidney. The synchronous or metachronous development of >or=2 primary soft tissue sarcomas has been reported. These are primary soft tissue sarcomas occurring at multiple soft tissue sites without pulmonary or lymphatic involvement. It is often difficult to distinguish between the synchronous or metachronous appearance of a second primary and soft tissue sarcoma metastasis. This article presents a case of a 17-year-old adolescent boy who presented with simultaneous enlarging masses involving the skull and thigh. Open biopsies confirmed synovial sarcoma in both regions. Staging studies, including computed tomography (CT) of his chest, abdomen/pelvis and bone scan were otherwise negative for metastasis.

Stroke risk factor, pattern and outcome in patients with cancer

OBJECTIVE

To investigate risk factors, stroke pattern and outcome in stroke patients with cancer.

METHODS

A retrospective review of all stroke patients with cancer (n = 69) admitted to Bankstown-Lidcombe Hospital, Sydney, Australia, between January 1999 and December 2004 was conducted, and comparison made to age- and gender-matched non-cancer stroke patients admitted to the same hospital during the same period.

RESULTS

Vascular risk factors did not significantly differ between cancer and non-cancer groups. There was a trend towards greater risk of intracerebral haemorrhage in the cancer group vs the non-cancer group. Previous deep vein thrombosis was more common, and prothrombin time and activated partial thromboplastin time were prolonged in the cancer group vs the non-cancer group. More patients died in hospital in the cancer group vs the non-cancer group.

CONCLUSIONS

Coagulation disorders are more likely to be seen in stroke patients with cancer, and patients with cancer have a higher in-hospital post-stroke mortality.

Risk Factor, Pattern, Etiology and Outcome in Ischemic Stroke Patients with Cancer: A Nested Case-Control Study

BACKGROUND

Coagulation disorders are seen in cancer patients, but it is not clear whether cancer predisposes stroke patients to unique characteristics. The aim of the study was to investigate risk factors, pattern,etiology and outcome in stroke patients with cancer.

METHODS

A retrospective review of all ischemic stroke (IS) patients with cancer (n = 56) admitted to Bankstown-Lidcombe Hospital, Sydney, Australia, between January 1999 and December 2004 was conducted and comparison made to age- and gender-matched noncancer IS patients admitted to the same hospital during the same period.

RESULTS

Vascular risk factors and stroke pattern were comparable in cancer and noncancer groups. Post-stroke thrombotic episodes (myocardial infarction, deep vein thrombosis or pulmonary emboli) were more common in the cancer group than in the noncancer group (11 vs. 0%, p = 0.031). Depression was also more common in the cancer group than in the noncancer group (14 vs. 2%, p = 0.039). There was a tendency for more patients in the cancer group to die in hospital (30 vs. 14%, p = 0.078).

CONCLUSIONS

Coagulation disorders were more likely to be seen in stroke cancer patients, and patients with cancer tended to have a higher in-hospital post-stroke mortality. Larger sample size studies may identify further differences in the characteristics of stroke patients with cancer.

Systemic tumor embolism mimicking gefitinib ('IRESSA')-induced interstitial lung disease in a patient with lung cancer

We describe a 55-year-old man with advanced adenocarcinoma of the lung who received gefitinib ('IRESSA'). After gefitinib administration for 7 months, computed tomography scan of the chest demonstrated diffuse ground glass opacity and he was suspected to have developed gefitinib-induced interstitial lung disease (ILD). However, transbronchial lung biopsy (TBLB) revealed tumor cells in the middle-size lung vessels. Afterwards, multiple infarctions of the brain, spleen and left kidney were detected. Then, he was considered to have developed systemic tumor emboli, a rare complication. The clinical presentation of this patient was difficult to discriminate from that of ILD, and TBLB was useful in the differential diagnosis.

Incidence and etiology of cerebrovascular disease in patients with malignancy

Cerebrovascular disease is common in cancer patients and often arises from mechanisms unique to malignancy. Direct tumor effects include intratumoral hemorrhage, arterial and venous sinus invasion by tumor mass or leptomeningeal infiltrates, and tumor emboli. Complications of chemotherapy, radiation therapy, and hematopoietic stem-cell transplantion for cancer can occur before, during, or years after treatment. Coagulopathic conditions involve disseminated intravascular coagulation, thrombocytopenia, nonbacterial thrombotic endocarditis, and cerebral intravascular coagulation. Finally, septic infarction from fungal or bacterial sepsis and infectious vasculitis manifest in cancer patients immunocompromised by malignancy or cancer therapy. In many cases a combination of mechanisms is causative, and both hemorrhagic and ischemic stroke can occur simultaneously. Stroke type and mechanism, as well as the stage and pathology of the neoplasm, dictate proper management and help delineate prognosis.

Left ventricular intracardiac metastatic germ cell tumor presenting with hemorrhagic cerebrovascular event

We describe an unusual case of a 26-year-old man admitted with respiratory distress and found to have testicular cancer metastatic to the lung and heart. Twelve days after admission, the patient experienced multiple hemorrhagic strokes. Echocardiography demonstrated testicular cancer metastatic to the septal surface of the left ventricle of the heart with presumed embolization to the cerebrovascular region. The patient received chemotherapy and radiation therapy to the areas of tumor mass with subsequent resolution of tumor burden. This is the first reported case of metastasis from embryonal carcinoma of the testis to the left ventricle of the heart.

Perioperative stroke caused by arterial tumor embolism

Rarely, cancer invades a pulmonary vein and subsequently embolizes to the cerebral circulation, causing a stroke. Tumor embolism typically involves large, centrally located lung tumors. We report a case of immediate postoperative stroke caused by an arterial tumor embolism during pulmonary resection of metastatic sarcoma. This case is unique because the resected lesions were smaller than those previously associated with tumor embolism and unusual in that the tumors were peripherally located. Tumor embolization should be considered in the differential diagnosis of stroke after lung cancer surgery even with small, peripherally located pulmonary malignancies.

IMPLICATIONS

We present a case of stroke diagnosed in the recovery room after lung cancer resection. The cause of the stroke was tumor that embolized from the lung to the middle cerebral artery. Tumor embolism should be considered in the differential diagnosis of immediate postoperative stroke after lung cancer surgery.

Tumor embolus: a case report and review of the literature

Peripheral embolization of macroscopic tumor fragments is an uncommon occurrence. A patient with a previously undiagnosed primary lung adenocarcinoma who presented with an acutely ischemic limb is described. Following review of the literature, the characteristics of tumor embolization are discussed.

Cerebrovascular complications in cancer patients

Coagulation disorders are common in cancer patients. In patients with solid tumors, a low-grade activated coagulation can result in systemic and cerebral arterial or venous thrombosis. Cancer treatments may also contribute to this coagulopathy, which usually, but not exclusively, occurs in the setting of advanced malignant disease. There may be TIAs or cerebral infarctions. Because of the widespread distribution of cerebral thromboses, there may be a superimposed encephalopathy; sometimes this is the only sign. Concurrent systemic thrombosis is present in many patients and is a useful clue to the diagnosis. In cerebral venous occlusion, the initial symptom is usually a headache. Except for cerebral intravascular coagulation that is unassociated with NBTE, neuriomaging studies usually demonstrate one or more parenchymal infarctions. MRI or MRV may demonstrate venous thrombosis. The laboratory evidence of coagulopathy is difficult to distinguish from the asymptomatic coagulopathy that often accompanies advanced cancer, and the test results must be interpreted cautiously. NBTE can be diagnosed by transesophageal echocardiography. There is no established treatment for the thrombotic coagulopathy associated with cancer, but anticoagulation should be considered. In leukemia and lymphoma, the coagulopathy is typically acute DIC that can lead to systemic and brain hemorrhages. It is especially common in acute myelogenous leukemias. The clinical signs of cerebral hemorrhage are fulminant and may be fatal. The bleeding usually occurs in the brain or subdural compartment, and rarely in the subarachnoid space. The diagnosis can be suspected by the clinical setting and by systemic thrombosis or hemorrhage. It can be established by examination of the peripheral smear, the platelet count, and tests of coagulation function. Therapy of acute DIC is controversial and should be individualized for the clinical setting. Cerebrovascular disorders can complicate metastatic or primary tumor in the brain, skull, dura, or leptomeninges. The clinical signs of infarction are indistinguishable from other causes of stroke, except that tumor-related venous occlusion will usually first produce signs of increased intracranial pressure. The diagnosis of tumor-related infarction can usually be established by neuroimaging studies that show infarction and may show extracerebral sites of tumor. CSF examination is useful in diagnosing leptomeningeal metastasis. A search for lung or cardiac tumor should be performed when embolic tumor infarction is suspected. Primary or metastatic tumors in the brain or dura may hemorrhage, producing the initial clinical signs of the brain tumor or a change in chronic signs induced by the tumor. There are helpful clues to a neoplastic hemorrhage on brain CT or MRI scans. The brain hemorrhage may require evacuation and the underlying tumor will usually require additional antineoplastic treatment. Hyperleukocytosis (extreme elevation of the cell count) in acute myelogenous leukemia is a less common cause of brain hemorrhage in recent years because of improved methods to lower the cell count. Cerebral arterial or venous thrombosis is sometimes the result of cancer therapy. The attribution of thrombosis to chemotherapy in many published cases is only speculative, because carefully conducted prospective studies that include investigation for other thrombotic causes are not available. The best-known associations with thrombosis are L-asparaginase, which is typically used in the induction therapy of acute lymphocytic leukemia, and combination hormonal therapy and chemotherapy for breast cancer. Radiation to the head and neck, typically administered for head and neck epithelial cancers or lymphoma, may result in delayed carotid atherosclerosis. The distribution of stenosis or occlusion is within the radiation portal and is typically more extensive than is atherosclerosis that develops in the absence of radiation. Small clinical series suggest that surgical treatment is equally effective as in nonirradiated carotid atherosclerosis. In children, the cerebral vessels can be affected by brain radiation resulting in stenosis or occlusion. Brain hemorrhages can result from chemotherapy effects on the hemostatic system or a microangiopathic anemia. Hemorrhages from radiation-induced vascular abnormalities are rare. Opportunistic infections, especially fungal infections, can complicate cancer or its treatment. Septic cerebral emboli may result in focal cerebral signs, seizures, or encephalopathy. Sometimes there is an associated hemorrhagic vasculitis or cerebritis. Rarely, mycotic aneurysms may bleed. A high index of suspicion is needed to diagnose fungal infection because of the difficulty in culturing the organism from the blood or CSF. A clinician can usually establish the cause of stroke in the cancer patient by performing a careful review of the clinical setting--including the type and extent of cancer and the type of antineoplastic therapy--in which the stroke occurred. Systemic thrombosis, embolism, or hemorrhage can be a clue to the cause, and appropriate neuroimaging and coagulation studies to aid in the diagnosis are available. Therapy may ameliorate symptoms or prevent further episodes. The identification of one of these unusual stroke syndromes that leads to the diagnosis of an occult and treatable cancer can be particularly rewarding.

Brain tumor masquerading as stroke

Discriminating brain tumor from stroke in patients presenting with acute focal neurologic signs and symptoms is crucial to avoid improper treatment, or delay correct treatment of the brain tumor patient. Data from the era before computed tomography (CT) suggests that 3% of patients with brain tumors are initially thought to have had a stroke. Our goal was to see if this has improved in the CT era. We reviewed hospital charts of all patients admitted to the Johns Hopkins Hospital with a brain tumor during a one year period. Eleven (4.9%) of the 224 patients discharged with a diagnosis of brain tumor were initially thought to have had a stroke. Seven had primary brain tumors and 4 had metastatic tumors. Patients who were originally misdiagnosed were significantly older (p = 0.01) and more likely to have a Glioblastoma Multiforme (p = 0.04) than those correctly diagnosed. Eighty-two percent of those misdiagnosed had no prior history of cancer compared to 59% of patients correctly diagnosed. Distinguishing the acute presentation of brain tumor and stroke remains an important diagnostic consideration. Physicians should recognize that while CT is frequently employed for acute neurologic deficits to exclude intracranial hemorrhage, CT may not be sufficient to exclude brain tumor. A prospective study is needed to confirm these findings.

Tumor invasion of the pulmonary veins: a unique source of systemic embolism detected by transesophageal echocardiography

Two patients with a malignancy involving the lungs and spontaneous systemic embolization in whom transesophageal echocardiography detected masses consistent with tumor invading the pulmonary veins are reported. In the first patient, tumor embolization resulted in acute aortic obstruction. Transesophageal echocardiography revealed tumor present in the pulmonary veins that extended into the left atrium. This was confirmed by magnetic resonance imaging. The second patient had a stroke. Transesophageal echocardiography demonstrated a mass in the right pulmonary vein in this patient as well. In patients with pulmonary malignancy who have a systemic embolic event, tumor emboli from the pulmonary vein should be included in the differential diagnosis of possible causes of the event. Transesophageal echocardiography is a valuable tool for diagnosis of tumor involvement of the pulmonary veins in such patients.

Fatal intravascular synovial sarcoma in a 31-year-old woman

A 31-year-old woman presented with acute right abdominal pain of 5 hours' duration. Imaging studies showed obstruction and dilatation of the inferior vena cava. The patient suffered a cardiopulmonary arrest; during emergency surgery 230 g of "clot-like" material was removed from the inferior vena cava, right heart, and pulmonary arteries. The patient died the following day. Pathologic examination of the resected material showed a biphasic synovial sarcoma. At autopsy only a minimal amount of residual tumor was present in the wall of the inferior vena cava. Tumor embolization from another site was excluded on the basis of radiologic studies and autopsy findings. This appears to be the second reported case of intravascular synovial sarcoma and the first reported case with a fatal outcome.

Malignant arterial tumor embolization

Malignant arterial tumor emboli large enough to cause ischemia or organ infarction are a rare, but often fatal, complication of neoplastic disease. The majority of arterial emboli are associated with primary or secondary pulmonary malignancies. The sites where they impact are similar in distribution to arteriosclerotic emboli, and the treatment follows well-established principles developed for the treatment of arteriosclerotic emboli. The results of embolectomy in accessible sites are very good, thus treatment should always be attempted. A case of a superior mesenteric tumor embolus occurring after pneumonectomy is reported, together with a review of all published cases of arterial tumor emboli of sufficient size to cause organ infarction or ischemia.

Multiple tumor emboli after pneumonectomy

Systemic arterial tumor embolization is a rare complication after pulmonary resection. It may occur with primary or metastatic pulmonary malignancies, and is more frequently associated with pneumonectomy than with lesser pulmonary resections. Despite the rarity of this complication, tumor emboli should be considered in the etiology of extremity, cerebral, or multiorgan ischemia occurring during the perioperative period in patients undergoing pulmonary resections for malignancy.

Intraoperative transesophageal echocardiographic localization of tumor embolus during pneumonectomy

We describe a patient undergoing pneumonectomy for large-cell carcinoma, which at the time of surgery was found to invade the pulmonary veins. Transesophageal echocardiography was used to confirm and localize suspected tumor embolization during surgery. Although tumor embolization from the pulmonary veins has been previously reported in the literature, this is the first case, to our knowledge, of transesophageal echocardiographic documentation of such an occurrence. The use of echocardiography in patients at potential risk for tumor involvement of the pulmonary veins is discussed.

Left atrial tumor embolization during pulmonary resection: review of literature and report of two cases

In the past 10 years, 2 patients were seen with metastatic sarcoma to the lower lobe of the lung and extension into the left atrium. In both patients, an attempt to squeeze the intracardiac portion of the tumor into the lung at the time of lobectomy ended in near-catastrophic complications: In the first patient, a saddle embolus occluded both femoral arteries, and in the other, obstruction of the mitral valve orifice and cardiac arrest occurred. This approach is mentioned only to condemn it. Our recommended approach is outlined to prevent this technical mistake in the future.

Cardiopulmonary metastatic lesions of osteosarcoma and associated cerebral infarction

Osteogenic sarcoma frequently disseminates by hematogenous routes. A 32-year-old patient underwent evaluation for an acute cerebral infarction. Cardiac auscultation disclosed an abnormal diastolic sound. Echocardiographic examination revealed a large left atrial mass, which was found at thoracotomy to be metastatic osteogenic sarcoma. Cerebral computed tomographic scans at the time of initial examination and 3 months later demonstrated new cerebral lesions consistent with metastatic growths. The abrupt cerebral infarction, other clinical findings, and results of diagnostic studies strongly suggested that the acute cerebrovascular event was the result of metastatic cerebral embolization from the tumor material found in the thorax. Cerebral infarction is an unusual and catastrophic complication of thoracic metastatic lesions of osteogenic sarcoma.