Arterial thrombosis associated with adjuvant chemotherapy for breast carcinoma: a Cancer and Leukemia Group B Study

Arterial Thrombosis in Patients with Cancer

Patients with cancer are at increased risk of arterial thromboembolic disease due to the presence of risk factors common to both the development of cancer and arterial thrombosis, the cancer itself, and the treatments provided to treat cancer. We review here the epidemiology and pathophysiology of arterial thromboembolic disease in cancer, along with its prevention and treatment strategies. We also propose a generalized approach for the management of arterial thromboembolic disease in this patient population.

Exploring the Link between Head and Neck Cancer and the Elevated Risk of Acute Myocardial Infarction: A National Population-Based Cohort Study

Enhanced screening protocols for cancer detection have increased survival in patients with head and neck cancer (HNC), which highlights the need to address the sequelae of therapy-induced cardiovascular complications. This study was conducted to assess the incidence and risk of acute myocardial infarction (AMI) in patients with HNC who have not undergone radiation or chemotherapy using a comprehensive, population-based cohort dataset. A total of 2976 individuals without cancer and 744 individuals with HNC were matched using the propensity score method. The findings indicated that the occurrence rates of AMI were comparable between the HNC (2.19) and non-cancer groups (2.39). Cox regression analysis did not demonstrate a significant increase in the risk of AMI in patients with HNC (hazard ratio: 0.93, 95% confidence interval: 0.50-1.73). No increased risk of AMI was observed in the HNC group compared to the non-cancer group, regardless of the time since the HNC diagnosis. Subgroup analyses showed no notable differences in the AMI risk between the groups when considering sex, age, comorbidities, and cancer type. This study showed that patients with HNC who have not been treated with radiation or chemotherapy did not exhibit an increased incidence or risk of AMI compared to individuals without cancer.

Anticoagulation for the Prevention of Arterial Thrombosis in Ambulatory Cancer Patients: Systematic Review and Meta-Analysis

Background

The risk of arterial thrombotic events (ATEs) is high among patients on systemic anticancer therapies. Despite the efficacy of anticoagulants in the prevention of cancer-associated venous thromboembolism, it is unknown whether anticoagulation is effective to prevent ATEs.

Objectives

This study sought to examine the efficacy and safety of anticoagulants in ATE prevention among ambulatory cancer patients.

Methods

We performed a systematic review using Medline, Embase, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) from inception to May 21, 2022, and included studies comparing oral or parenteral anticoagulation with no anticoagulation among ambulatory patients receiving systemic anticancer therapy with no other indication for anticoagulation. The primary outcome was ATE (myocardial infarction, ischemic stroke, intra-abdominal arterial embolism, or peripheral artery occlusion). The secondary outcomes were major and nonmajor bleeding and all-cause mortality.

Results

Fourteen randomized trials involving low-molecular-weight heparins, direct oral anticoagulants, and warfarin were included. ATEs were captured as coefficacy endpoints or adverse events. Anticoagulant use was not associated with a reduction in ATEs compared with placebo or standard treatment (RR: 0.73, 95% CI: 0.50-1.04; P = 0.08; I2 = 0%). RRs of major and minor bleeding were 1.56 (95% CI: 1.12-2.17) and 2.25 (95% CI: 1.45-3.48) with anticoagulant use. In 13 trials that reported all-cause mortality, risk of death was not reduced with anticoagulants (RR: 0.99; 95% CI: 0.95-1.02; P = 0.38; I2 = 0%).

Conclusions

Anticoagulants did not reduce ATE risk among ambulatory patients on systemic anticancer therapy and were associated with increased bleeding. Based on the current data, anticoagulants have a limited role in ATE prevention in this population as a whole.

Cancer-Associated Thrombosis: Risk Factors, Molecular Mechanisms, Future Management

Venous thromboembolism (VTE) is a major health problem in patients with cancer. Cancer augments thrombosis and causes cancer-associated thrombosis (CAT) and vice versa thrombosis amplifies cancer progression, termed thrombosis-associated cancer (TAC). Risk factors that lead to CAT and TAC include cancer type, chemotherapy, radiotherapy, hormonal therapy, anti-angiogenesis therapy, surgery, or supportive therapy with hematopoietic growth factors. There are some other factors that have an effect on CAT and TAC such as tissue factor, neutrophil extracellular traps (NETs) released in response to cancer, cancer procoagulant, and cytokines. Oncogenes, estrogen hormone, and thyroid hormone with its integrin αvβ3 receptor promote angiogenesis. Lastly, patient-related factors can play a role in development of thrombosis in cancer. Low-molecular-weight heparin and direct oral anticoagulants (DOACs) are used in VTE prophylaxis and treatment rather than vitamin K antagonist. Now, there are new directions for potential management of VTE in patients with cancer such as euthyroid, blockade of thyroid hormone receptor on integrin αvβ3, sulfated non-anticoagulant heparin, inhibition of NETs and stratifying low and high-risk patients with significant bleeding problems with DOACs.

The incidence of myocardial infarction and stroke in head and neck cancer patients

Various treatment modalities are used for head and neck cancer (HNC). This study analyzed the incidence and risks of myocardial infarction (MI) and stroke by cancer site and treatment modality in 22,737 patients newly diagnosed with HNC registered in the Korean National Health Insurance Service database in 2007–2013. An additional 68,211 patients without HNC, stroke, or MI were identified as the control group. The risks for MI (hazard ratio [HR] = 1.38, 95% confidence interval [CI] 1.24–1.53), stroke (HR = 1.48, 95% CI 1.37–1.60), and mortality (HR = 5.30, 95% CI 5.14–5.47) were significantly higher in the HNC group. Analysis by cancer site showed the risk of MI and mortality was highest in hypopharynx cancer, while the risk of stroke was highest in nasopharynx and paranasal sinus cancer. Analysis by treatment modality showed the highest risks for MI (HR = 1.88, 95% CI 1.31–2.69) and mortality (HR = 2.95, 95% CI 2.75–3.17) in HNC patients receiving chemotherapy (CT) alone, while HNC patients receiving CT with surgery had the highest risk for stroke (HR = 1.81, 95% CI 1.14–2.88). Careful attention to MI and stroke risks in HNC patients is suggested, especially those who received both CT and radiotherapy.

Acute arterial thrombosis during adjuvant Adriamycin-cyclophosphamide chemotherapy in a patient with early breast cancer: A case report

RATIONALE

Cancer and chemotherapy individually confer hypercoagulability and increased risks of thrombosis. Most thromboembolic complication after breast cancer chemotherapy was venous thrombosis after multiagent chemotherapy. Arterial thrombosis is extremely rare in early breast cancer patients receiving adjuvant chemotherapy.

PRESENTING CONCERNS

A 55-year-old woman with right breast cancer presented to the emergency department with sudden pain, numbness, and swelling in her left hand. She underwent breast conserving surgery and sentinel lymph node biopsy 2 months before the visit. She received the second cycle of adjuvant Adriamycin-cyclophosphamide chemotherapy 5 days before.

INTERVENTIONS

Computed tomography angiography revealed acute arterial thrombosis in the left brachial, radial, and ulnar arteries. Unfractionated heparin was initiated immediately, followed by brachial and radial-ulnar thrombectomy, restoring perfusion to the extremity. The postoperative course was uncomplicated; she was discharged on warfarin at a daily dose of 4 mg.

OUTCOMES

Chemotherapy was discontinued. Anticoagulation with warfarin was continued. She subsequently received adjuvant endocrine therapy with an aromatase inhibitor and adjuvant radiotherapy.

MAIN LESSONS

Despite the low risks of arterial thrombosis in breast cancer, it is a devastating complication with significant morbidity and mortality. Thromboprophylaxis should be considered in those at risk. Immediate anticoagulant therapy and surgical intervention should be considered in affected cases.

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.

Dynamic platelet function is markedly different in patients with cancer compared to healthy donors

Despite a fivefold increased risk of thromboembolism in patients with cancer, the mechanism of arterial thromboembolism is poorly understood. To address this, we investigated platelet function in cancer patients and healthy controls using an assay that mimics the arterial vasculature. Blood samples from cancer patients (n = 36) and healthy controls (n = 22) were perfused through custom-made parallel-plate flow chambers coated with von Willebrand factor (VWF) under arterial shear (1,500 s^-1). Multiparameter measurements of platelet interactions with the immobilized VWF surface were recorded by digital-image microscopy and analyzed using custom-designed platelet-tracking software. Six measured parameters that characterize in detail the surface motion and surface binding of several hundred platelets per blood sample differed significantly in those with cancer from the healthy donors. In particular, it was found that patients with cancer had decreased numbers of platelets interacting, translocating and adhering to VWF. There were also reductions in the speed and distances that platelets traveled on VWF in comparison to healthy controls. Platelet function differed between those with early-stage cancer compared to those with later stage cancer. Patients with advanced cancer had an increased number of platelets stably adhering to VWF and greater platelet surface coverage after a given time of interaction. To the best of our knowledge, our results demonstrate for the first time that dynamic platelet function is markedly different in patients with cancer compared to healthy donors.

Bavituximab plus paclitaxel and carboplatin for the treatment of advanced non-small-cell lung cancer

OBJECTIVE

Bavituximab is a phosphatidylserine (PS)-targeting monoclonal antibody with immune-modulating and tumor-specific vascular targeting properties. Preclinical studies have shown activity against numerous solid tumors and at least an additive effect in combination with chemotherapy. This study evaluated bavituximab in combination with paclitaxel and carboplatin in patients with previously untreated, locally advanced or metastatic non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

This phase II, open-label study (NCT00687817) was conducted in 49 patients with stage IIIB/IV NSCLC utilizing a Simon two-stage design. Patients were treated with up to six cycles of carboplatin area under the concentration-time curve (AUC) 5 plus paclitaxel 175 mg/m2 every 21 days with weekly bavituximab 3 mg/kg followed by bavituximab monotherapy until progression or unacceptable toxicity.

RESULTS

The primary efficacy endpoint of overall response rate (ORR) was 40.8% (complete response [CR] 2.0%, partial response [PR] was 38.8%). Median progression-free survival (PFS) and overall survival (OS) were 6.0 and 12.4 months, respectively. Treatment-related adverse events (AEs) occurred in 40.8% of patients. The most common treatment-related AEs were anemia (10.2%), asthenia, vomiting, paresthesia, anorexia, and fatigue (6.1% each). One patient with a central, cavitating squamous tumor developed fatal hemoptysis and aspiration.

CONCLUSION

Bavituximab in combination with paclitaxel-carboplatin as first-line therapy demonstrated a tolerable safety profile and potential efficacy in this single-arm phase II trial in patients with advanced local or metastatic NSCLC. Randomized trials with this regimen are in progress.

CLINICALTRIALSGOV IDENTIFIER

NCT00687817.

Breast cancer as an acquired thrombophilic state

Cancer is an acquired thrombophilic condition manifested by increased incidence of venous and arterial thromboembolic complications. Despite progress that has been achieved in treatments over the recent years, thromboembolism remains a major complication in patients with breast cancer; it is accompanied by significant morbidity and mortality. Approximately, 1% of breast cancer patients develop venous thromboembolism within 2 years with the highest incidence occurring in the 6 months post diagnosis. Metastatic disease and their comorbidities are the strongest predictors of the development of thrombotic event. The diagnosis of venous thromboembolism is associated with a higher risk of death within 2 years of diagnosis. Thromboembolic events in cancer patients range from abnormal laboratory coagulation tests without specific symptoms to massive thomboembolism and disseminated intravascular coagulation. The underlying pathophysiology is complex and includes the prothrombotic properties of cancer cells, which can be enhanced by anticancer treatment modalities, such as surgery, hormonal agents, and chemotherapy. Primary thromboprophylaxis in cancer patients should be individualized according to risk. For secondary prevention, several clinical studies have shown that low molecular weight heparin has improved patients' compliance, cancer outcomes and overall survival. This review summarizes the available data on the pathogenesis and clinical approach of hemostatic changes in breast cancer.

Development of bavituximab, a vascular targeting agent with immune-modulating properties, for lung cancer treatment

Bavituximab is a chimeric monoclonal antibody directed against the membrane phospholipid phosphatidylserine. Phosphatidylserine exposure is increased on endothelial cells and apoptotic cancer cells in solid tumors, allowing tumor-specific targeting of bavituximab. Bavituximab binding results in tumor vessel occlusion and enhanced antitumor immunity. Preclinical investigations have demonstrated efficacy as monotherapy and in combination with other modalities against multiple cancer types. Phase I clinical trials of bavituximab monotherapy and in combination with chemotherapy in adults with refractory solid tumors have been completed. Phase II trials of bavituximab in combination with chemotherapy for the first- and second-line treatment of advanced non-small-cell lung cancer are currently ongoing. This article summarizes the preclinical development and clinical experience with bavituximab in non-small-cell lung cancer.

The chemotherapy metabolite acrolein upregulates thrombin generation and impairs the protein C anticoagulant pathway in animal-based and cell-based models

BACKGROUND

Thrombosis is a common complication in cancer patients receiving chemotherapy regimens that include cyclophosphamide. However, the mechanisms by which these agents increase this risk are largely uncharacterized.

OBJECTIVES

To examine the effects of cyclophosphamide and its metabolite acrolein on procoagulant and anticoagulant pathways in both cell-based and animal-based models.

METHODS

Thrombin and activated protein C (APC) generation were measured in defibrinated plasma exposed to acrolein-treated endothelial and smooth muscle cells. Tissue factor (TF) activity was measured on acrolein-treated cells. Cell surface levels of phosphatidylserine, TF, endothelial protein C receptor and thrombomodulin were measured. Healthy BALB/c mice received injections of saline (control), acrolein, or cyclophosphamide; blood was collected, and plasma thrombin-antithrombin (TAT) complex, protein C and APC levels were analyzed.

RESULTS

Exposure of acrolein-treated endothelial and smooth muscle cells to defibrinated plasma increased thrombin generation in the plasma. This was associated with enhanced phosphatidylserine exposure and/or increased TF activity on acrolein-treated cells. Despite elevated levels of thrombin generation, plasma APC levels were not elevated. In vivo, treatment of mice with cyclophosphamide and acrolein resulted in elevations of plasma TAT complex levels, whereas APC levels remained low.

CONCLUSIONS

This is the first study to examine thrombin generation and the APC pathway in chemotherapy-treated mice. Cyclophosphamide and acrolein appear to upregulate procoagulant pathways, while impairing endogenous anticoagulant pathways. This may explain, in part, the increased risk of thrombosis observed in cancer patients receiving cyclophosphamide-containing chemotherapy.

Arterial thrombosis associated with adjuvant chemotherapy for breast cancer: a case report

PURPOSE

To report a case of arterial thrombosis in a 63-year-old female undergoing treatment with multiagent chemotherapy for breast cancer. An overview of the prevalence and pathogenesis of the disorder, clinical diagnosis, and treatment are discussed.

DATA SOURCES

Case report, diagnostic evidence, and scientific literature.

CONCLUSIONS

Arterial thrombosis is an extremely rare complication of multichemotherapy treatment of breast cancer. Although the risk of arterial thromboembolism appears to be low, it can have devastating complications that result in significant morbidities and, sometimes, death.

IMPLICATIONS FOR PRACTICE

As the risk of arterial thrombosis is low, many healthcare providers may not be aware of this potentially serious complication. Thrombosis prophylaxis should be considered for patients with risk factors. In cases where arterial thrombosis occurs, immediate thrombolitic therapy or operative intervention should be considered.

The Hemostasis Apparatus in Pancreatic Cancer and Its Importance beyond Thrombosis

Laboratory evidence of aberrant coagulation is found in the majority of patients with advanced pancreatic cancer and a clinical consequence of this is the high incidence and prevalence of vascular thromboembolic events. Other sequelae are hypothesized to be the facilitation and acceleration of mechanisms that define the malignant phenotype, such as invasion, trafficking and anchoring, establishing the metastatic niche and inducing angiogenesis. We review the in vitro and preclinical evidence that supports the role of the coagulation apparatus in the metastatic process of pancreatic cancer, with a particular emphasis on interaction of this pathway with clinically-targeted growth factor receptor pathways. Links between hemostasis, angiogenesis and epidermal growth factor pathways and their significance as therapeutic targets are considered.

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.

Doença arterial obstrutiva periférica agravada pela utilização de gemcitabina para tratamento de neoplasia pancreática: relato de caso e revisão da literatura

Este estudo tem por objetivo relatar um caso de isquemia crítica de membro inferior associada a quimioterapia com gemcitabina. O relato descreve o caso de um paciente de 68 anos submetido a duodenopancreatectomia devido a tumor no pâncreas. Um mês depois da operação, o paciente realizou quatro sessões de quimioterapia com gemcitabina, durante um mês. Após 30 dias, o paciente desenvolveu sintomas de doença arterial obstrutiva periférica, e duas semanas depois, isquemia crítica do membro inferior direito. O exame por imagem demonstrou doença arterial difusa associada à oclusão femoropoplítea com reenchimento distal precário. O paciente foi submetido a uma tentativa de revascularização que, devido às condições locais, foi malsucedida, resultando na amputação do membro no nível da coxa.

Doit-on prescrire une prophylaxie de la maladie thromboembolique aux patients porteurs d'un cathéter central et/ou recevant unechimiothérapie pour une tumeur solide?

INTRODUCTION

Deep venous thrombosis and pulmonary embolism are well-recognized complications of cancer, especially in patients with a venous access device or receiving chemotherapy. The pathogenic mechanisms of thrombosis in cancer patients involve a complex interaction between the patient's tumor cells and hemostatic system. Chemotherapy and central venous catheters increase the risk of thromboembolism. Prophylactic treatment for these patients remains controversial.

METHODS

We conducted a systematic literature review using the Medline database and abstract books for meetings of the American Society of Clinical Oncology and the American Society of Hematology since 2000. Our search focused on clinical trials of primary prevention of venous catheter-related thrombosis or prevention of chemotherapy-related venous thromboembolism in cancer patients.

RESULTS

Ten studies evaluating primary prevention of patients with central catheters were identified, and their results are contradictory. Currently only one study has examined prevention of chemotherapy-related venous thromboembolism, in women with metastatic breast cancer. Its results cannot be extrapolated to other tumors.

CONCLUSION

Systematic prophylaxis cannot yet be recommended. In the near future we must improve our knowledge of the risk factors of these complications. Prophylaxis should be individualized for each patient. New anticoagulant drugs should be tested in cancer patients.

Phase II study of temozolomide and thalidomide in patients with metastatic melanoma in the brain: high rate of thromboembolic events (CALGB 500102)

BACKGROUND

Preliminary studies suggesting that extended-dose temozolomide with thalidomide is safe and active in patients with metastatic melanoma have led to frequent use of this oral regimen. To confirm these observations the combination was tested in a multicenter Phase II trial in patients with melanoma brain metastases.

METHODS

Eligible patients had melanoma brain metastases, with or without systemic metastases. The primary endpoint was response rate in brain metastases. Patients received temozolomide at a dose of 75 mg/m2/day for 6 weeks with a 2-week rest between cycles, and thalidomide (escalated to 400 mg/day for patients age < 70 years or to 200 mg/day for patients age > or = 70 years). A 2-stage design required > or = 3 responses in the first 21 patients before enrolling 29 additional patients in the second stage.

RESULTS

Sixteen eligible patients were enrolled. No objective responses were observed. The median survival was 23.9 weeks. Seven patients withdrew because of tumor progression; 7 were removed during Cycle 1 because of adverse events, including allergic reaction (1 patient), severe fatigue (1 patient), sudden death (1 patient), and thromboembolic events (pulmonary embolism in 3 patients and deep vein thrombosis in 1 patient); 2 patients withdrew when the study was suspended and subsequently closed. No associations could be established between baseline characteristics and toxicity.

CONCLUSIONS

The proportion of patients with lethal or potentially life-threatening adverse events was high (0.31, 95% confidence interval, 0.11-0.59), and the absence of objective responses made it unlikely that further accrual would demonstrate the efficacy of the regimen. These observations provide little support for the use of this combination for melanoma brain metastases unless safe and effective methods to prevent thrombosis are developed.

Peripheral arterial thrombosis induced by chemotherapy in ovarian carcinoma coexisted with endometrial carcinoma

INTRODUCTION

Most patients with peripheral arterial occlusion have underlying atherosclerosis. Peripheral arterial thrombosis induced by chemotherapy in gynecological malignancies is rare.

CASE REPORT

A 60-year-old woman was diagnosed with ovarian carcinoma coexisting with endometrial carcinoma after surgical histopathological examination. Chemotherapy was started on postoperative day 11. On day 2 of chemotherapy, she developed bilateral lower extremity cyanosis. Thrombocytopenia due to chemotherapy was diagnosed and treated with repeated platelet transfusions. Anticoagulant therapy was also continued. However, the patient worsened steadily and died of liver dysfunction due to multiple liver metastases.

CONCLUSION

Although arterial thrombosis induced by chemotherapy is rare, it is important for physicians to consider this possibility in the course of treatment with cytotoxic agents because this complication has serious health implications.

The cancer stem cell: evidence for its origin as an injured autoreactive T cell

This review explores similarities between lymphocytes and cancer cells, and proposes a new model for the genesis of human cancer. We suggest that the development of cancer requires infection(s) during which antigenic determinants from pathogens mimicking self-antigens are co-presented to the immune system, leading to breaking T cell tolerance. Some level of autoimmunity is normal and necessary for effective pathogen eradication. However, autoreactive T cells must be eliminated by apoptosis when the immune response is terminated. Apoptosis can be deficient in the event of a weakened immune system, the causes of which are multifactorial. Some autoreactive T cells suffer genomic damage in this process, but manage to survive. The resulting cancer stem cell still retains some functions of an inflammatory T cell, so it seeks out sites of inflammation inside the body. Due to its defective constitutive production of inflammatory cytokines and other growth factors, a stroma is built at the site of inflammation similar to the temporary stroma built during wound healing. The cancer cells grow inside this stroma, forming a tumor that provides their vascular supply and protects them from cellular immune response.

As cancer stem cells have plasticity comparable to normal stem cells, interactions with surrounding normal tissues cause them to give rise to all the various types of cancers, resembling differentiated tissue types. Metastases form at an advanced stage of the disease, with the proliferation of sites of inflammation inside the body following a similar mechanism. Immunosuppressive cancer therapies inadvertently re-invigorate pathogenic microorganisms and parasitic infections common to cancer, leading to a vicious circle of infection, autoimmunity and malignancy that ultimately dooms cancer patients. Based on this new understanding, we recommend a systemic approach to the development of cancer therapies that supports rather than antagonizes the immune system.

Vascular Toxicity of Antineoplastic Agents

Among the various deleterious effects of cancer chemotherapy, vascular toxicity is the least well recognized. This lack of recognition may be because the vasculotoxic phenomena are not unique to antineoplastic agents, can occur in patients without exposure to these agents, and the fact cancer itself may produce a hypercoagulable state. As a result, many vascular events either go unnoticed, are ignored, and/or are attributed to the underlying malignancy. Many antineoplastic therapies are associated with various vascular phenomena that range from simple phelibitis to lethal microangiopathy. Recognition of these events is important to minimize the morbidity and even prevent unnecessary deaths. Herein we review the vascular syndromes that have been reported in association with antineoplastic agents.

Incidence of ischemic stroke post-chemotherapy: a retrospective review of 10,963 patients

OBJECTIVE

Vascular occlusion is not an uncommon event in malignancy. However, the frequency of ischemic stroke after chemotherapy has been mentioned only occasionally in clinical studies. A large-scale study is lacking.

METHODS

A retrospective study was conducted at Chang Gung Memorial Hospital, Kaohsiung, Taiwan, to analyze the incidence of ischemic stroke post-chemotherapy, further, to evaluate a possible causative relationship between the ischemic stroke and the chemotherapy regimen, the interval between the latest chemotherapy session and onset of ischemic stroke and the survival of patients with ischemic stroke post-chemotherapy. The data were retrieved from the Cancer Database from 1993 to 2004.

RESULTS

During this period, a total of 10,963 patients, with malignancies were followed-up for 1 month after chemotherapy, underwent 45,294 chemotherapy sessions. Among this group, there were 15 patients experiencing 16 ischemic strokes within the first month after the latest chemotherapy. Among them, 14 patients were followed-up until death and one patient was lost in follow-up after discharge against medical advice. The incidence of post-chemotherapy ischemic stroke was 0.137% and the frequency of chemotherapy cycles complicated by ischemic stroke was 0.035%. Adenocarcinoma was the most common histological type not only in ischemic stroke (40%) but also in overall patients (36.7%). The hemispheric stroke with middle cerebral artery territory involvement was the most common image finding. Platinum compounds, especially cisplatin, were the most commonly used chemotherapeutic agents for ischemic stroke patients. Twelve (75%) of these 16 ischemic strokes occurred within 10 days of the latest chemotherapy session and 10 (62.5%) occurred after the first cycle of chemotherapy. The median survival after ischemic stroke was 4 weeks.

CONCLUSION

Our results provide valuable data on the relationship between malignancy, treated with chemotherapy, and ischemic stroke. The risk of ischemic stroke after chemotherapy is predicted by the use of cisplatin-based chemotherapy not cancer histologic type. Infarction usually involves the territorial subtype, causes obvious neurological disabilities and carries a grave prognosis.

Increased incidence of stroke in women with breast cancer

Meta-analyses have shown an excess of vascular deaths in women with breast cancer given radiotherapy (RT). In women with breast cancer, RT to the supraclavicular lymph nodes gives a substantial radiation dose to the proximal carotid artery. RT is known to increase the risk of carotid stenosis and ischaemic stroke in head and neck cancer. A study base of 25,171 women with breast cancer was defined. A linkage between the study base and the Hospital Discharge Register yielded 1766 women who were diagnosed with a stroke after a breast cancer. The observed number of strokes was compared with the expected number in the background population. The Relative Risk (RR) of stroke in the study group with breast cancer was 1.12 (95% Confidence Interval (CI)=1.07-1.17). The increased risk was confined to the subtype cerebral infarction, RR=1.12 (95% CI=1.05-1.19). A statistically significant increase in the risk of stroke was seen among women with a history of breast cancer. Whether this risk is associated with the breast cancer disease per se or related to any treatment requires further study.

Stroke Risk and Tamoxifen Therapy for Breast Cancer

BACKGROUND

Tamoxifen, which is used widely to treat, and increasingly to prevent, breast cancer, has been associated with increased risk of stroke. We assessed the impact of tamoxifen treatment for breast cancer on the risk of stroke, considering dose, duration, and recency of use of tamoxifen and known stroke risk factors.

METHODS

We conducted a nested case-control study of stroke after breast cancer among female Los Angeles County residents enrolled in a large health maintenance organization when diagnosed with breast cancer between January 1, 1980, and July 1, 2000. We obtained information on breast cancer treatment and stroke risk factors through medical record review and telephone interviews. The association (odds ratio [OR] and 95% confidence interval [CI]) between tamoxifen and stroke risk was determined by using a conditional logistic regression model, adjusting for menopausal status and history of hypertension and diabetes. All statistical tests were two-sided.

RESULTS

Of 11 045 women with breast cancer, 179 met stroke eligibility criteria and were individually matched to two stroke-free control subjects with breast cancer on age and year of breast cancer diagnosis. The mean age at breast cancer diagnosis was 66.6 years (standard deviation [SD] = 12.3 years), and the mean at-risk period (i.e., the time between breast cancer diagnosis and first stroke or comparable time period for control subjects) was 5.7 years (SD = 4.5 years). Tamoxifen use was not associated with risk of stroke, either overall (OR = 1.0, 95% CI = 0.6 to 1.6) or in subgroups defined by duration, dose, or recency of use. Chemotherapy, but not a specific chemotherapy regimen, was associated with an increased risk of stroke, regardless of tamoxifen use (no tamoxifen use, OR = 2.8, 95% CI = 1.3 to 6.3; tamoxifen use OR = 2.2, 95% CI = 1.2 to 4.1).

CONCLUSIONS

Tamoxifen use is not associated with increased stroke risk. Further exploration of possible increased stroke risk following chemotherapy treatment for breast cancer is needed.

Adjuvant Endocrine Therapy Compared With No Systemic Therapy for Elderly Women With Early Breast Cancer: 21-Year Results of International Breast Cancer Study Group Trial IV

Purpose: Increasing numbers of older women are affected by early breast cancer, because of prolonged life expectancy and the increasing incidence of breast cancer with age. The role of adjuvant therapy for this population is still a matter of debate. We reviewed the long-term outcome of a mature trial comparing endocrine treatment versus no adjuvant therapy in older women with node-positive breast cancer.

Patients and Methods: From 1978 to 1981, 349 women 66 to 80 years of age with pathologically involved lymph nodes after total mastectomy and axillary clearance were randomly assigned to receive 12 months of adjuvant tamoxifen plus low-dose prednisone (p+T) or no adjuvant therapy. Three hundred twenty patients were eligible.

Results: At 21 years’ median follow-up, 1 year of p+T significantly prolonged disease-free survival (DFS; P = .003) and overall survival (P = .05; 15-year DFS, 10% ± 3% v 19% ± 3%; hazard ratio, 0.71; 95% CI, 0.58 to 0.86). When comparing competing causes of failure (breast cancer recurrence and deaths before breast cancer recurrence), p+T was far superior in controlling breast cancer recurrence (P = .0003), but the improvement was seen mainly in soft tissue sites. Conversely, patients in the p+T group were more likely to die before a breast cancer recurrence (P = .03).

Conclusion: This trial demonstrates that significant treatment benefits continue to be observed in older patients treated for 1 year with p+T. Despite issues relating to competing causes of failure, older breast cancer patients can benefit from treatment and should be considered for trials of adjuvant systemic therapy.

Coagulopathic complications in breast cancer

Patients with cancer are highly susceptible to thromboembolic complications, which account for a significant percentage of the morbidity and mortality of the disease. Up to 15% of patients with clinically overt cancer present with venous thromboembolism during the course of their disease. Moreover, patients with cancer represent 20% of all patients in whom deep venous thrombosis and pulmonary embolism are diagnosed. This prothrombotic state in cancer can occur due to the ability of tumor cells to directly activate the blood-clotting cascade and cause thrombosis or induce procoagulant properties and inhibit anticoagulant properties of vascular endothelial cells, platelets, monocytes, and macrophages. It also is well established that this prothrombotic tendency in patients with cancer can be enhanced greatly by anticancer treatments, such as surgery and chemotherapy. This phenomenon can be seen in patients with breast cancer, particularly after surgery and chemotherapy. Increased clotting risk also is associated with the use of central venous access devices, commonly used to administer chemotherapeutic agents in patients with cancer. Thrombosis prophylaxis, therefore, should be considered for patients with breast cancer who are at risk before and during intervention. In the current review, the authors discuss the problem of thromboembolism in patients with breast cancer who are undergoing therapy, the mechanisms by which thromboembolisms occur, and the potential strategies by which these events may be prevented. Better understanding of these pathogenetic pathways may lead to the development of more targeted strategies to prevent thromboembolism in patients with cancer.

Venous thromboembolism and cancer: risks and outcomes

Cancer and its treatments are well-recognized risk factors for venous thromboembolism (VTE). Evidence suggests that the absolute risk depends on the tumor type, the stage or extent of the cancer, and treatment with antineoplastic agents. Furthermore, age, surgery, immobilization, and other comorbid features will also influence the overall likelihood of thrombotic complications, as they do in patients without cancer. The role of hereditary thrombophilia in patients with cancer and thrombosis is still unclear, and screening for this condition in cancer patients is not indicated. The most common malignancies associated with thrombosis are those of the breast, colon, and lung, reflecting the prevalence of these malignancies in the general population. When adjusted for disease prevalence, the cancers most strongly associated with thrombotic complications are those of the pancreas, ovary, and brain. Idiopathic thrombosis can be the first manifestation of an occult malignancy. However, intensive screening for cancer in patients with VTE often does not improve survival and is not generally warranted. Independently of the timing of cancer diagnosis (before or after the VTE), the life expectancy of cancer patients with VTE is relatively short, because of both deaths from recurrent VTE and the cancer itself. Patients with cancer and acute VTE who take anticoagulants for an extended period are at increased risk of recurrent VTE and bleeding. A recent randomized trial, the Randomized Comparison of Low Molecular Weight Heparin versus Oral Anticoagulant Therapy for Long-Term Anticoagulation in Cancer Patients with Venous Thromboembolism (CLOT) study, showed that low molecular weight heparin may be a better treatment option for this group of patients. The antineoplastic effects of anticoagulants are being actively investigated with promising preliminary results.

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.

The hypercoagulable state of malignancy: pathogenesis and current debate

A hypercoagulable or prothrombotic state of malignancy occurs due to the ability of tumor cells to activate the coagulation system. It has been estimated that hypercoagulation accounts for a significant percentage of mortality and morbidity in cancer patients. Prothrombotic factors in cancer include the ability of tumor cells to produce and secrete procoagulant/fibrinolytic substances and inflammatory cytokines, and the physical interaction between tumor cell and blood (monocytes, platelets, neutrophils) or vascular cells. Other mechanisms of thrombus promotion in malignancy include nonspecific factors such as the generation of acute phase reactants and necrosis (i.e., inflammation), abnormal protein metabolism (i.e., paraproteinemia), and hemodynamic compromise (i.e., stasis). In addition, anticancer therapy (i.e., surgery/chemotherapy/hormone therapy) may significantly increase the risk of thromboembolic events by similar mechanisms, e.g., procoagulant release, endothelial damage, or stimulation of tissue factor production by host cells. However, not all of the mechanisms for the production of a hypercoagulable state of cancer are entirely understood. In this review, we attempt to describe what is currently accepted about the pathophysiology of the hypercoagulable state of cancer. We also discuss whether or not to screen patients with idiopathic deep venous thrombosis for an underlying malignancy, and whether this would be beneficial to patients. It is hoped that a better understanding of these mechanisms will ultimately lead to the development of more targeted treatment to prevent thromboembolic complications in cancer patients. It is also hoped that antithrombotic strategies may also have a positive effect on the process of tumor growth and dissemination.

Acute abdomen during adjuvant chemotherapy: superior mesenteric artery thrombosis associated with CMF chemotherapy

We report a case of superior mesenteric artery thrombosis in a 57-year-old woman undergoing chemotherapy for T1N1M0, breast cancer. Although cancer itself is associated with an increased risk of thrombotic events, treatment with chemotherapy and/or tamoxifen in breast cancer patients increases this risk. Most cases reported are of venous thromboembolism; arterial events are rare.

Effects of high-dose methotrexate on the hemostatic system in childhood acute lymphoblastic leukemia

BACKGROUND

Thromboembolic and hemorrhagic complications are significant causes of death in patients with malignancy. These are well-known with the use of certain drugs. This study was planned to investigate whether there was any effect of high-dose methotrexate on the hemostatic system in childhood acute lymphoblastic leukemia.

PROCEDURE

To evaluate the hemostatic system, we investigated coagulation screening tests (prothrombin time, activated partial thromboplastin time, and fibrinogen), coagulation inhibitors (protein C, protein S, and antithrombin III), and fibrinolytic system (fibrin degradation products and tissue plasminogen activator). These parameters were measured in 35 cycles of high dose-methotrexate (3 g/m(2)) of 20 childhood acute lymphoblastic leukemia cases at baseline and on days 1 and 7 after the therapy.

RESULTS

We found that high-dose methotrexate administration adversely affected both the coagulation system (prolonged prothrombin time and activated partial thromboplastin time and decreased fibrinogen levels) and coagulation inhibitors (decreased protein C, protein S, antithrombin III) on day 1 after chemotherapy compared to the baseline values. The hemostatic parameters began to improve on day 7 after chemotherapy, except for fibrin degradation products. Tissue plasminogen activator levels were not changed with the therapy.

CONCLUSIONS

Coagulation cascade (prolonged prothrombin time and activated partial thromboplastin time and decreased fibrinogen) and coagulation inhibitors (decreased protein C, protein S, and antithrombin III levels) have been found to be affected by high-dose methotrexate therapy, but these transient changes did not cause clinical thromboembolic or hemorrhagic complications.

Thromboembolic events during chemotherapy for germ cell cancer: a cohort study and review of the literature

PURPOSE

To evaluate the risk of major thromboembolic complications in male germ cell cancer patients receiving cisplatin-based chemotherapy and to review the literature on this subject.

PATIENTS AND METHODS

One hundred seventy-nine germ cell cancer patients treated between January 1979 and May 1997 in our hospital were analyzed with respect to risk factors for developing thromboembolic events, such as baseline tumor characteristics, prior tumor therapy, administration of cytostatic agents, and the use of antiemetic drugs. The patients were treated with a variety of combination chemotherapy regimens, primarily cisplatin-containing combination regimens.

RESULTS

Of the 179 patients, 15 patients (8.4%) were identified who developed a total of 18 major thromboembolic complications in the time period between the start of chemotherapy and 6 weeks after administration of the last cytostatic drug in first-line treatment. Of these 18 events, three (16.7%) were arterial events, including two cerebral ischemic strokes, and 15 (83. 3%) were venous thromboembolic events, including 11 pulmonary embolisms. One (5.6%) of the 18 events was fatal. Liver metastases (odds ratio, 4.9; 95% confidence interval, 1.1 to 20.8) and the administration of high doses of corticosteroids (>/= 80 mg dexamethasone per cycle; odds ratio, 3.5; 95% confidence interval, 1. 2 to 10.3) as antiemetic therapy were identified as risk factors for the development of major thromboembolic complications.

CONCLUSION

Germ cell cancer patients who receive chemotherapy, in particular those who have liver metastases or receive high doses of corticosteroids, are at considerable risk of developing thromboembolic complications.

Chemotherapy and thrombosis in gynecologic malignancy

Thromboembolism is a severe and frequent problem in gynecologic malignancy. The average DVT incidence during chemotherapy of 5% might represent the lower range of incidence because < 55% of thrombotic complication manifest clinical signs. However, it seems likely that in addition to chemotherapy other risk factors such as menopausal status, BMI of patients, or type of preceding surgery must coincide before thrombosis manifests. While monitoring of patients using sophisticated coagulation tests did not identify patients' risk for DVT during chemotherapy, an evaluation of the coagulation status before initiating chemotherapy is recommended. Patients with a venous access device (e.g., indwelling central venous catheter or with port cart) are at a particularly high risk for DVT. This has to be considered when cytoreductive therapy is given. Thrombosis prophylaxis, orally or subcutaneously, should only be considered in a subpopulation of patients who offer a combination of the aforementioned risk factors. Thrombosis prevention trials during chemotherapy found a significant reduction of DVT in patients treated with anticoagulants.

A prothrombotic state in breast cancer patients treated with adjuvant chemotherapy

Cancer is often associated with abnormal activation of coagulation leading to a prothrombotic state. Some chemotherapeutic agents used for cancer may induce thrombosis but their biological alterations in the hemostatic system are not yet well understood. This study evaluated alterations of coagulative and fibrinolytic parameters following chemotherapy. In plasma samples of 38 patients (median age: 49 years) receiving CMF (schedule 1-21 or 1-8) for Stage II breast cancer, we evaluated: PT, aPTT, antithrombin III (AT-III), protein C (PC), protein S (PS), thrombin-antithrombin complex (TAT), prothrombin fragment F 1 + 2 (F 1 + 2), fibrinogen (Fbg), tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor (PAI-1) and D-dimer (D-D). PT, aPTT, and Fbg were determined with routine methods; AT-III, PC, and PS were measured with coagulative tests; PC and PS were also evaluated with immunoenzymatic methods, t-PA, PAI-1, D-D, TAT, and F 1 + 2 were measured with immunoenzymatic methods. All tests were performed immediately before starting therapy and after each cycle. A PC antigen decrease appeared soon after beginning therapy and lasted throughout chemotherapy. The lowest values were present after the first treatment both in the CMF 1-21 group (mean +/- SD = 72.5 +/- 10.8%) and in the CMF 1-8 group (mean +/- SD = 77.2 +/- 6.9%): PC activity was also decreased. PS antigen decreased after the first administration (mean +/- SD = 73.3 +/- 10% in CMF 1-21 group, and 72.5 +/- 4.9% in CMF 1-8 group): PS activity also decreased. PAI-1 antigen levels increased (mean +/- SD = 43.1 +/- 20.4 ng/ml in the CMF 1-21 group, and 37.5 +/- 12.2 ng/ml in CMF 1-8 group) lasting up to the last cycle. CMF provokes a trend toward hypercoagulability; this effect should be considered when chemotherapy is employed in advanced cancer patients at high risk for thrombosis, or in patients with other risk factors.

Coagulation disorders in cancer

Coagulation disorders are common in cancer patients. This article reviews the coagulation laboratory findings in these patients and the thromboembolic and hemorrhagic manifestations of malignancy. Among the many topics addressed are Trousseau's syndrome, disseminated intravascular coagulation, and acquired von Willebrand disease. Pathogenesis of the coagulation disorders and recommendations for treatment of various syndromes are discussed.

Multiple cerebral hemorrhages as a possible complication of antiblastic treatment with cyclophosphamide, methotrexate and fluoruracil (CMF) for breast cancer

In this paper we describe the case of a patient who underwent left breast radical mastectomy and corresponding removal of her axillary lymphonodes, for an infiltrating lobular cancer with massive colonizing (16 of 19 lymphonodes examined), stage T2N2M0. During chemotherapy with cyclophosphamide, methotrexate and 5 fluoruracil (CMF), the patient presented a symptomatology characterized by anarthria and dysphagia. These symptoms were the consequences of multiple cerebral hemorrhages unrelated to alterations in the coagulation process. The temporal relation with the pharmacological treatment and the lack of other explanations of the induced phenomenon lead us to hypothesize a cytotoxic mechanism due to the CMP treatment.