Context.—Cancer is characterized by the development of a prothrombotic state. Approximately 15% to 20% and 1.5% to 3.1% of cancer patients develop venous and arterial thrombosis, respectively, whereas 18% to 20% of idiopathic venous events are caused by an occult neoplasia. The highest risk is observed in hematologic, gastrointestinal, and lung malignancies, as well as in patients with active disease, especially in the first 3 months after cancer diagnosis. Hospitalization, surgical interventions, and implanted venous devices increase the thrombotic risk. Patients with metastatic disease, febrile neutropenia, infections, and severe comorbidities experience more frequently a thrombotic event. A contemporary prechemotherapy predictive model incorporates both clinical and biologic parameters, such as the primary cancer site, platelet count, white blood cell count, hemoglobin, use of erythropoietic agents, and body mass index. Several studies aim to clarify the prognostic value of tissue factor, P-selectin, thrombin generation, microparticles, and D-dimers. Objectives.—To summarize current views on epidemiology, risk factors, and predictive variables, discussing the future perspectives and existing limitations in clinical practice. Data Sources.—Review of published literature, including review papers, epidemiologic studies, and clinical trials, in online medical databases. Conclusions.—The thrombogenic properties of tumor cells affect the prognosis and quality of life for the cancer population. Despite the improved awareness and prompt use of thromboprophylaxis, recent studies reported increased rates of thrombotic events, whereas the annual risks for thrombosis recurrence and bleeding are 21% and 12%, respectively. The clinical use of risk factors and prognostic parameters could allow for patient risk stratification and individualization of anticoagulant treatment.

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.

Monoclonal antibodies (MoAbs) have been widely used in clinical hematology. As foreign macro-molecules, they can cause infusional reactions during the administration or within 24 hours after the infusion, which encompass a spectrum of mechanisms. Although most of these reactions are non-allergic, are often indistinguishable from true allergic reactions mediated by IgE immunoglobulins. The diagnosis is often challenging and relies mainly on clinical criteria. They occur during the first doses, soon after the initiation of treatment. The symptoms are usually well controlled by the immediate drug discontinuation or reduction of the infusion rate. The management remains largely supportive, consisting of oxygen, intravenous fluids, bronchodilators, antihistamines and steroids. Most of MoAb protocols recommend premedication with steroids and antihistamines and gradually escalating infusion rates. Increased medical and nursing vigilance is required and resuscitative equipment should always be readily available. These events affect patients' quality of life, leading to treatment delay or discontinuation and series of tests. The decision to rechallenge the treatment depends on severity grading, clinical parameters and treatment goals. This article provides an update of MoAbs used in clinical hematology. It summarizes the pathophysiology, the diagnostic approach, the preventive measures and treatment of MoAb-related reactions.