The coagulation system constitutes an important facet of the unique vascular microenvironment in which primary and metastatic brain tumors evolve and progress. While brain tumor cells express tissue factor (TF) and other effectors of the coagulation system (coagulome), their propensity to induce local and peripheral thrombosis is highly diverse, most dramatic in the case of glioblastoma multiforme (GBM), and less obvious in pediatric tumors. While the immediate medical needs often frame the discussion on current clinical challenges, the coagulation pathway may contribute to brain tumor progression through subtle, context-dependent, and non-coagulant effects such as induction of inflammation, angiogenesis, or by responding to iatrogenic insults (e.g. surgery). In this regard, the emerging molecular diversity of brain tumor suptypes (e.g. in glioma and medulloblastoma) highlights the link between oncogenic pathways and the tumor repertoire of coagulation system regulators (coagulome). This relationship may influence the mechanisms of spontaneous and therapeutically provoked tumor cell interactions with the coagulation system as a whole. Indeed, oncogenes (EGFR, MET) and tumor suppressors (PTEN, TP53) may alter the expression, activity, and vesicular release of tissue factor (TF), and cause other changes. Conversely, the coagulant microenvironment may also influence the molecular evolution of brain tumor cells through selective and instructive cues. We suggest that effective targeting of the coagulation system in brain tumors should be explored through molecular stratification, stage-specific analysis, and more personalized approaches including thromboprophylaxis and adjuvant treatment aimed at improvement of patient survival.
Therapy of Hodgkin lymphoma (HL) is a rapidly changing field due to plenty of currently emerging data. Treatment approaches are currently based on tailoring of therapy in order to achieve a maximal response with minimal toxicity. Since the median age of HL patients is 33 years and their prospective life expectancy another half a century, a major emphasis needs to be put on dramatic reduction of later toxicity. The assessment of the treatment effect should be based not only on progression-free survival, but should include evaluation of cardiac toxicity, secondary neoplasms, and fertility in the long-term follow-up. The ancient principle “first do no harm” should be central in HL therapy. Completion of ongoing and currently initiated trials could elucidate multiple issues related to the management of HL patients.
Hematopoietic stem cell transplantation is a highly specialized and unique medical procedure. Autologous transplantation allows the administration of high-dose chemotherapy without prolonged bone marrow aplasia. In allogeneic transplantation, donor-derived stem cells provide alloimmunity that enables a graft-versus-tumor effect to eradicate residual disease and prevent relapse. The first allogeneic transplantation was performed by E. Donnall Thomas in 1957. Since then the field has evolved and expanded worldwide. New indications beside acute leukemia and aplastic anemia have been constantly explored and now include congenital disorders of the hematopoietic system, metabolic disorders, and autoimmune disease. The use of matched unrelated donors, umbilical cord blood units, and partially matched related donors has dramatically extended the availability of allogeneic transplantation. Transplant-related mortality has decreased due to improved supportive care, including better strategies to prevent severe infections and with the incorporation of reduced-intensity conditioning protocols that lowered the toxicity and allowed for transplantation in older patients. However, disease relapse and graft-versus-host disease remain the two major causes of mortality with unsatisfactory progress. Intense research aiming to improve adoptive immunotherapy and increase graft-versus-leukemia response while decreasing graft-versus-host response might bring the next breakthrough in allogeneic transplantation. Strategies of graft manipulation, tumor-associated antigen vaccinations, monoclonal antibodies, and adoptive cellular immunotherapy have already proved clinically efficient. In the following years, allogeneic transplantation is likely to become more complex, more individualized, and more efficient.
Venous thromboembolism is a frequent and serious complication in patients with cancer. It is an independent prognostic factor of death in cancer patients and the second leading cause of death, but physicians often underestimate its importance, as well as the need for adequate prevention and treatment. Management of venous thromboembolism in patients with cancer requires the coordinated efforts of a wide range of clinicians, highlighting the importance of a multidisciplinary approach. However, a lack of consensus among various national and international clinical practice guidelines has contributed to knowledge and practice gaps among practitioners, and inconsistent approaches to venous thrombo-embolism. The 2013 international guidelines for thrombosis in cancer have sought to address these gaps by critically re-evaluating the evidence coming from clinical trials and synthesizing a number of guidelines documents. An individualized approach to prophylaxis is recommended for all patients.
Achievement of complete response (CR) to therapy in chronic lymphocytic leukemia (CLL) has become a feasible goal, directly correlating with prolonged survival. It has been established that the classic definition of CR actually encompasses a variety of disease loads, and more sensitive multiparameter flow cytometry and polymerase chain reaction methods can detect the disease burden with a much higher sensitivity. Detection of malignant cells with a sensitivity of 1 tumor cell in 10,000 cells (10–4), using the above-mentioned sophisticated techniques, is the current cutoff for minimal residual disease (MRD). Tumor burdens lower than 10–4 are defined as MRD-negative. Several studies in CLL have determined the achievement of MRD negativity as an independent favorable prognostic factor, leading to prolonged disease-free and overall survival, regardless of the treatment protocol or the presence of other pre-existing prognostic indicators. Minimal residual disease evaluation using flow cytometry is a sensitive and applicable approach which is expected to become an integral part of future prospective trials in CLL designed to assess the role of MRD surveillance in treatment tailoring.
The recognition that the development of cancer is associated with acquired immunodeficiency, mostly against cancer cells themselves, and understanding pathways inducing this immunosuppression, has led to a tremendous development of new immunological approaches, both vaccines and drugs, which overcome this inhibition. Both “passive” (e.g. strategies relying on the administration of specific T cells) and “active” vaccines (e.g. peptide-directed or whole-cell vaccines) have become attractive immunological approaches, inducing cell death by targeting tumor associated antigens. Whereas peptide-targeted vaccines are usually directed against a single antigen, whole-cell vaccines (e.g. dendritic cell vaccines) are aimed to induce robust responsiveness by targeting several tumor-related antigens simultaneously. The combination of vaccines with new immuno-stimulating agents which target “immunosuppressive checkpoints” (anti-CTLA-4, PD-1, etc.) is likely to improve and maintain immune response induced by vaccination.
Non-Hodgkin lymphoma (NHL) is one of the most common hematologic malignancies worldwide. The incidence of NHL has been rising for several decades; however, in the last 20 years, it reached a plateau. NHL incidence among males is significantly higher than in females. In addition to gender itself, gravidity has a protective role against NHL occurrence. Gender also matters in terms of NHL clinical characteristics. For example, female predominance was found in three extra-nodal sites (the breast, thyroid, and the respiratory system) occasionally involved in NHL. The diagnosis of NHL during pregnancy is associated with a unique clinical behavior. It is usually diagnosed in the second or third trimester and in advanced stage. Furthermore, the histological subtype is highly aggressive, and reproductive organ involvement is common. The reduced rate of NHL among females may be explained by direct effects of estrogens on lymphoma cell proliferation or by its effect on anti-tumor immune response. Gender has an important role in responsiveness to standard B cell NHL treatment. Among older adults, women benefited more from the addition of the anti-CD20 antibody rituximab to standard chemotherapy regimens. This phenomenon can be explained by the difference in clearance rate of rituximab that was found to be significantly lower among older females than older males. In mantle cell lymphoma, women receiving lenalidomide have higher rates of response. An understanding of the mechanisms responsible for gender-associated NHL differences will ultimately improve the clinical approach, allowing for a more accurate assessment of prognosis and patient-tailored treatment.
Gaucher disease (GD) is an inherited lysosomal disorder, originating from deficient activity of the lysosomal enzyme glucocerebrosidase (GCase). Normally, GCase hydrolyzes glucocerebroside (GC) to glucose and ceramide; however, impaired activity of this enzyme leads to the accumulation of GC in macrophages, termed "Gaucher cells". GD is associated with hepatosplenomegaly, cytopenias, skeletal complications and in some forms involves the central nervous system.
Coagulation abnormalities are common among GD patients due to impaired production and chronic consumption of coagulation factors. Bleeding phenomena are variable (as are other symptoms of GD) and include mucosal and surgical hemorrhages.
Four main etiological factors account for the hemostatic defect in GD: thrombocytopenia, abnormal platelet function, reduced production of coagulation factors, and activation of fibrinolysis. Thrombocytopenia relates not only to hypersplenism and decreased megakaryopoiesis by the infiltrated bone marrow but also to immune thrombocytopenia. Autoimmunity, especially the induction of platelet antibody production, might cause persistent thrombocytopenia.
Enzyme replacement therapy reverses only part of the impaired coagulation system in Gaucher disease. Other therapeutic and supportive measures should be considered to prevent and/or treat bleeding in GD. Gaucher patients should be evaluated routinely for coagulation abnormalities especially prior to surgery and dental and obstetric procedures.
The neurovascular unit is a key player in brain development, homeostasis, and pathology. Mental stress affects coagulation, while severe mental illnesses, such as recurrent depression and schizophrenia, are associated with an increased thrombotic risk and cardiovascular morbidity. Evidence indicates that the hemostatic system is involved to some extent in the pathogenesis, morbidity, and prognosis of a wide variety of psychiatric disorders. The current review focuses on emerging data linking coagulation and some psychiatric disorders.
Genetic aberrations have become a dominant factor in the stratification of myeloid malignancies. Cytogenetic and a few mutation studies are the backbone of risk assessment models of myeloid malignancies which are a major consideration in clinical decisions, especially patient assignment for allogeneic stem cell transplantation. Progress in our understanding of the genetic basis of the pathogenesis of myeloid malignancies and the growing capabilities of mass sequencing may add new roles for the clinical usage of genetic data. A few recently identified mutations recognized to be associated with specific diseases or clinical scenarios may soon become part of the diagnostic criteria of such conditions. Mutational study may also advance our capabilities for a more efficient patient selection process, assigning the most effective therapy at the best timing for each patient. The clinical utility of genetic data is anticipated to advance further with the adoption of deep sequencing and next-generation sequence techniques. We herein suggest some future potential applications of sequential genetic data to identify pending deteriorations at time points which are the best for aggressive interventions such as allogeneic stem cell transplantation. Genetics is moving from being mostly a prognostic factor to become a multitasking decision support tool for hematologists. Physicians must pay attention to advances in molecular hematology as it will soon be accessible and influential for most of our patients.
