Primary ambulatory thromboprophylaxis in patients with pancreatic cancer receiving chemotherapy: hope or hype?

Thrombosis is the second leading cause of death in cancer patients. Patients with pancreatic cancer (PC) have a very high risk of developing venous thromboembolism (VTE). Even though primary ambulatory thromboprophylaxis (PATP) could decrease this risk, there are uncertain issues with regard to the choice and dose of anticoagulants, duration of anticoagulant therapy, and patient selection criteria. In addition, the current practice guidelines on PATP in PC patients are equivocal. This review critically appraises the evidence on the use of PATP in PC patients receiving chemotherapy.

Thrombotic microangiopathy (TMA) in adult patients with solid tumors: a challenging complication in the era of emerging anticancer therapies.

Thrombotic microangiopathy (TMA) is a syndrome that encompasses a group of disorders defined by the presence of endothelial damage leading to abnormal activation of coagulation, microangiopathic hemolytic anemia and thrombocytopenia, occlusive (micro)vascular dysfunction, and organ damage. TMA may occur in patients with malignancy as a manifestation of cancer-related coagulopathy itself or tumor-induced TMA (Ti-TMA) as a paraneoplastic uncommon manifestation of Trousseau syndrome. TMA can also be triggered by other overlapping conditions such as infections or more frequently as an adverse effect of anticancer drugs (drug-induced TMA or Di-TMA) due to direct dose-dependent toxicity or a drug-dependent antibody reaction. The clinical spectrum of TMA may vary widely from asymptomatic abnormal laboratory tests to acute severe potentially life-threatening forms due to massive microvascular occlusion. While TMA is a rare condition, its incidence may progressively increase within the context of the great development of anticancer drugs and the emerging scenarios in supportive care in cancer. The objective of the present narrative review is to provide a general perspective of the main causes, the key work-up clues that allow clinicians to diagnose and manage TMA in patients with solid tumors who develop anemia and thrombocytopenia due to frequent overlapping causes.

Catheter-related thrombosis (CRT) in patients with solid tumors: a narrative review and clinical guidance for daily care.

Central venous access devices (CVADs) including central venous catheters and peripherally inserted central catheters (PICCs) are essential in the treatment of cancer. Catheter-related thrombosis (CRT) is the most frequent non-infectious complication associated with the use of central lines. The development of CRT may cause to delays in oncologic treatment and increase morbidity leading to potentially life-threatening complications. Several local and systemic risk factors are associated with the development of CRT and should be taken into account to prevent CRT by standardizing appropriate catheter placement and maintenance. The use of primary pharmacological thromboprophylaxis in order to avoid CRT is not routinely recommended, although it can be considered in selected cases. Recommendations for the management of established CRT are based on the extrapolation of anticoagulation for lower limb venous thrombosis. The present review summarizes the current evidence and recommendations for the prevention and management of CRT and identifies areas that require further research.

Current Controversies in Inferior Vena Cava Filter Placement: AJR Expert Panel Narrative Review.

Despite inferior vena cava (IVC) filter practice spanning over 50 years, interventionalists face many controversies in proper utilization and management. This article reviews recent literature and offers opinions on filter practices. IVC filtration is most likely to benefit patients at high risk of iatrogenic pulmonary embolus during endovenous intervention. Filters should be used selectively in patients with acute trauma or who are undergoing bariatric surgery. Retrieval should be attempted for perforating filter and fractured filter fragments when imaging suggests feasibility and favorable risk-to-benefit ratio. Antibiotic prophylaxis should be considered when removing filters with confirmed gastrointestinal penetration. Anticoagulation solely because of filter presence is not recommended except in patients with active malignancy. Anticoagulation while filters remain in place may decrease long-term filter complications in these patients. Patients with a filter and symptomatic IVC occlusion should be offered filter removal and IVC reconstruction. Physicians implanting filters may maximize retrieval by maintaining physician-patient relationships and scheduling follow-up at time of placement. Annual follow-up allows continued evaluation for removal or replacement as appropriate. Advanced retrieval techniques increase retrieval rates but require caution. Certain cases may require referral to experienced centers with additional retrieval resources. The views expressed should help guide clinical practice, future innovation, and research.

Venous thromboembolism risk in patients with hormone receptor-positive HER2-negative metastatic breast cancer treated with combined CDK 4/6 inhibitors plus endocrine therapy versus endocrine therapy alone: a systematic review and meta-analysis of randomized controlled trials.

PURPOSE: Approximately 70% of patients with metastatic breast cancer (MBC) are hormone receptor (HR)-positive. Recent studies have shown that CDK4/6 inhibitors (CDKI) improve survival in combination with ET in HR-positive, HER2-negative MBC. The risk of venous thromboembolism (VTE) is 3-4 times higher in patients with breast cancer (BC) than in patients without cancer. The risk is even higher in BC patients receiving ET and chemotherapy. The aim of the study was to determine the VTE risk of CDKIs plus ET versus ET alone in patients with HR-positive, HER2-negative MBC. METHODS: We performed a systematic review and meta-analysis to demonstrate the risk of VTE in patients with HR-positive HER2-negative MBC treated with combined CDKIs and ET versus ET alone. RESULTS: Eight randomized controlled trials (RCT) with a total of 4,557 patients were eligible. The study arms comprised of palbociclib or ribociclib or abemaciclib plus ET while the control arms utilized placebo plus ET. The VTE events were 56 (2%) in the CDKIs plus ET group compared to 10 (0.5%) in the control group. Pooled relative risk (RR) for VTE was 2.62 (95% CI 1.21-5.65; P = 0.01) and the risk difference (RD) was 0.01 (95% CI 0.00-0.03; P = 0.02). Over a median follow-up of up to 36 months, RR was 3.18 (95% CI 1.22-8.24; P = 0.02) and RD was 0.03 (95% CI 0.01-0.06, P = 0.008). CONCLUSIONS: Our meta-analyses demonstrated that the addition of CDKIs to ET in patients with HR-positive HER 2-negative MBC contribute to a higher incidence of VTE. Further trials are required to define the actual relation and definitive incidence of VTE with different CDKIs.

Impact of Primary Ambulatory Thromboprophylaxis (PATP) with Low-Molecular Weight Heparins (LMWHs) on Survival in Patients with Lung Cancer Receiving Chemotherapy.

Lung cancer (LC) is the leading cause of cancer mortality. PATP was provided in experimental trials to decrease the venous thromboembolism (VTE), with ultimate aim to improve overall survival (OS). We undertook an updated systematic review and meta-analysis of randomized controlled trials (RCTs) to determine the impact of PATP with LMWHs on OS and VTE in patients with LC. 5443 patients with LC from nine RCTs were included. The pooled hazard ratio (HR) for OS was 1.02 (95% CI 0.83 to 1.26; P = 0.83) and for progression or metastasis-free survival was 1.03 (95% CI 0.86 to 1.24; P = 0.74). The pooled risk ratio (RR) for VTE was 0.54 (95% CI 0.43 to 0.69; P < 0.00001) and the risk difference (RD) was-0.03 (- 0.05 to - 0.02; P < 0.00001). Our analysis showed no survival advantage with the addition of PATP with LMWHs to standard chemotherapy in patients with LC, regardless of histology or stages of small cell LC.

Comparative outcomes of thrombocytopenic acute leukemic patients with venous thromboembolism at a Comprehensive Cancer Center.

Patients with hematological malignancies often have severe thrombocytopenia, which poses problems when making thrombosis management decisions. A retrospective study was conducted to analyze the clinical outcomes associated with different management options in acute leukemic patients with thrombocytopenia (≤ 50 × 109/L) following an acute venous thromboembolic event. A total of 74 patients were divided into three treatment groups: observation only (n = 30); anticoagulation (n = 23); or inferior vena cava placement (n = 21). Multivariate analysis showed that anticoagulant administration was significantly associated with improved overall survival without an increased rate of clinical relevant bleeding events when compared to other thrombosis management modalities. This study notes that dose adjusted-anticoagulant therapy may offer a safe and clinical advantageous strategy for the treatment and secondary prevention of recurrent venous thrombosis in thrombocytopenic patients with hematologic malignancies.

Risk of intracranial hemorrhage associated with therapeutic anticoagulation for venous thromboembolism in cancer patients: a systematic review and meta-analysis.

Intracranial hemorrhage (ICH) in cancer patients can result from tumor bleeding and from antitumor and anticoagulation therapy. The effect of anticoagulation on the incidence of ICH in cancer patients has not been quantified. Our objective was to determine the risk of intracranial hemorrhage associated with anticoagulation therapy for cancer-associated venous thromboembolism (VTE). Systematic review and meta-analysis of studies assessing the safety of anticoagulation therapy in patients with cancer-associated VTE. The primary endpoint of interest was the incidence of ICH and secondary outcomes included all major bleeding, and the time to ICH and major bleeding. After identifying 595 studies, five studies and 2089 patients were included in the analyses. We found that the relative risk (RR) for ICH was 0.494, 95 % CI (0.105-2.331) when low molecular weight heparin (LMWH) with vitamin K antagonist (VKA) anticoagulants were compared. No statistically significant differences in risk were measured. The risk of major bleeding using any type of anticoagulation therapy in patients with cancer-associated VTE was RR 0.853, 95 % CI (0.549, 1.327). After meta-analytic review of data published through August 2015, we conclude that therapeutic anticoagulation with LMWH given ≤6 months does not increase the risk of ICH in cancer patients compared to VKA. The risk of ICH in cancer patients is also similar to that of non-cancer patients. Available data were insufficient to determine if the ICH risk increase changes when the duration of anticoagulation is >6 months.

Performance of 4T score and heparin-platelet factor 4 antibody in the diagnosis of heparin-induced thrombocytopenia (HIT) in cancer.

Cancer patients have characteristics which significantly influence the 4T score and heparin-platelet factor 4 antibody (H-PF4 ab). Our aim was to determine among cancer patients the correlation of the 4T score and H-PF4 ab with the serotonin release assay (SRA). We performed a retrospective analysis of records of cancer patients in whom H-PF4 polyclonal (IgG, IgM and IgA) enzyme-linked immunosorbent assay (ELISA) and SRA were evaluated. Cases were defined as heparin induced thrombocytopenia (HIT) when SRA confirmed the diagnosis. Logistic regression model and the receiver operating characteristic curves were conducted to identify the optimal cutting point for the optical density (OD) and 4T score to discriminate the SRA status. Among 246 patients, the optimal cutoff of 4T score for HIT diagnosis was 5 (sensitivity 90.0%, specificity 73.6%), and the optimal cutoff of H-PF4 polyclonal ELISA OD was 1.004 (sensitivity 81.8%, specificity 97.0%). Our findings suggest that cancer patients may need higher cutoff values for the 4T score. Conventional H-PF4 ab testing seem to perform similarly for the diagnosis of HIT when compared to published data from non-cancer cohorts. Additional studies are necessary to confirm our findings.

Thymoma complicated by acquired amegakaryocytic thrombocytopenia and pure red cell aplasia.

Although the association of pure red cell aplasia (PRCA) and aplastic anemia with thymoma is well-known, acquired amegakaryocytic thrombocytopenia (AAMT) is not a recognized paraneoplastic manifestation of thymoma. This report discusses a patient with recurrent thymoma complicated by myasthenia gravis, PRCA, and AAMT. Both PRCA and AAMT are diagnosed after a thymoma recurrence, 11 years after complete resection of the initial tumor and 9 months after chemotherapy for the relapsed disease. Both PRCA and AAMT responded to immunosuppression with cyclosporine, corticosteroid, and an abbreviated course of antithymocyte globulin, achieving a very good erythroid response and a complete remission for AAMT, suggesting that AAMT, although extremely rare, can be an immune-mediated paraneoplastic manifestation of thymoma.

Durvalumab-induced Pure White Cell Aplasia.

Immune checkpoint inhibitors (ICI) have gained approval as a treatment for a wide array of cancers. Their mechanism of action prevents the inactivation of cytotoxic T-cells, allowing for its cytotoxic response. However, the upregulation of the immune system by ICI also leads to many undesired adverse events known as immune-related adverse events (irAEs), ranging from dermatologic manifestations, such as rashes, to inflammation of mucous membranes, to hematologic toxicities. Here, we report a case of ICI-induced pure white cell aplasia, secondary to the agent durvalumab, which responded to treatment with filgrastim, prednisone, and cyclosporine. ICI-neutropenia accounts for 0.6% of all irAEs or 17% of hematologic irAEs. Given the rarity of hematologic irAEs, the available treatment guidelines are based on expert consensus. As ICI becomes more widely used, we can expect an increase in the prevalence of rare irAEs as well. This case report aims to present a rare side effect of ICI and demonstrate its response to immunosuppressive therapy while providing guidance for future clinicians and further elucidating the mechanism behind these irAEs.

Updated meta-analysis of randomized controlled trials on primary outpatient thromboprophylaxis in patients with gastric and gastroesophageal junction cancers receiving chemotherapy.

Advanced gastric cancer is a highly thrombogenic cancer per Khorana score. Recent clinical practice guidelines suggest primary outpatient thromboprophylaxis (POTP) for patients with a Khorana score ≥2. We performed an updated meta-analysis to evaluate the benefit of POTP in patients with gastric cancer and gastroesophageal junction cancers receiving chemotherapy. Randomized controlled trials with reduction in venous thromboembolism (VTE) as a primary or secondary endpoint were incorporated. A total of 631 patients from subgroups of three randomized controlled trials were included. The VTE incidence was 1.6% and 5.1% in POTP and control groups, respectively (risk ratio 0.31; confidence interval 0.11 to 0.83; P = 0.02), with a number needed to treat of 29 to prevent one VTE event. Even though the recent clinical practice guidelines suggest POTP in patients with gastric cancer and gastroesophageal junction cancers, our meta-analysis findings do not support the routine use of POTP in those patients.

Nonhematological Manifestations of Pernicious Anemia.

Pernicious anemia (PA) is an autoimmune disease characterized by cobalamin deficiency (CD) due to immune-mediated chronic atrophic gastritis (CAG). CD results from poor absorption of dietary cobalamin from the terminal ileum, triggered by positive intrinsic factor (IF) antibodies. It is the most common cause of CD worldwide. Despite advances in understanding biochemistry and pathogenesis of PA, its diagnosis can be extremely challenging as the disease may present with hematological as well as nonhematological manifestations and also because of unreliable serum cobalamin assays. Nonhematological manifestations may present in a patient with PA even in the absence of hematological findings. Herein, an overview of common and uncommon nonhematological manifestations of PA is discussed.

Meta-analysis of randomized controlled trials on primary ambulatory thromboprophylaxis in patients with ovarian cancer receiving chemotherapy.

Ovarian cancer (OC) is highly associated with venous thromboembolism (VTE). The OC cells stimulate thrombin generation, and chemotherapy potentiates the prothrombotic effect of cancer cells by damaging endothelium and enhancing hypercoagulability. Recently, primary ambulatory thromboprophylaxis (PATP) has been studied as a potential treatment in cancer patients undergoing chemotherapy with an aim of reducing the incidence of VTE and potentially prolonging survival. A meta-analysis was performed of randomized controlled trials of PATP vs control in patients with OC receiving chemotherapy. The primary outcome measure was the incidence of VTE. The secondary outcome measure was the incidence of major bleeding complications. Two articles published between 2012 and 2020 fulfilled selection criteria. The incidence of VTE was 0.9% in the PATP group and 1.8% in the control group. However, the pooled risk ratio was not statistically significant at 0.69 (95% CI: 0.08 to 5.67; P = 0.73). The absolute risk difference was -0.03 (95% CI, -0.17 to 0.11; P = 0.66). There was no statistically significant reduction in VTE by providing PATP to patients with OC receiving chemotherapy. Routine PATP should not be recommended in ambulatory OC patients. Future randomized trials are necessary to define the high-risk subset of OC patients who may benefit from PATP.

Meta-analysis of randomized controlled trials on primary ambulatory thromboprophylaxis in patients with nonpancreatic gastrointestinal cancers receiving chemotherapy.

Primary ambulatory thromboprophylaxis (PATP) in patients with solid malignancies is not routinely indicated. We performed a meta-analysis of randomized controlled trials (RCTs) to determine the benefit and risk of PATP in patients with nonpancreatic gastrointestinal cancers receiving chemotherapy. RCTs with venous thromboembolism (VTE) reduction as primary or secondary endpoints were included. A total of 1932 patients from subgroups of 3 RCTs were eligible. The VTE incidence was 1.26% and 2.55% in PATP and control arms, respectively (risk ratio 0.49; confidence interval 0.25 to 0.96; P = 0.04), with a number needed to treat of 78 to prevent one VTE event. In gastric and gastroesophageal junction cancer patients, the VTE incidence was 1.37% and 3.40% in PATP and control arms, respectively (risk ratio 0.40; confidence interval 0.13 to 1.24; P = 0.11). PATP should not be recommended in patients with nonpancreatic gastrointestinal cancers on chemotherapy.

Pernicious anemia: Pathophysiology and diagnostic difficulties.

Pernicious anemia (PA) is the most common cause of vitamin B12 (cobalamin) deficiency anemia in the world. It is an autoimmune disease, comprising of salient features of autoimmune chronic atrophic gastritis (CAG) and cobalamin deficiency (CD). Although the anemia was first described as pernicious, it may well be controlled with vitamin B12 replacement. The onset and progression of PA is often insidious. Alternatively, patients may have no anemic symptoms since they become acclimatized to the subtle nature of the disease. Oftentimes, there is a possibility that the underlying disease may be missed unless a full blood count (FBC) is investigated, leading to hindrance in the treatment journey. Diagnostic challenges remain tangible for many practicing clinicians, since there is lack of reliable cobalamin assays to diagnose CD as well as clinical mimics, which simulate many other hematological conditions, such as myelodysplastic syndrome, acute leukemia, sideroblastic anemias, bone marrow failure states, thrombotic microangiopathy, and thromboembolism. Moreover, prompt recognition of the symptoms of CD is also vital, because some neurologic sequalae may become irreversible despite replenishing cobalamin. Herein, we discuss a literature review on the pathophysiology, challenging clinical presentations and diagnostic difficulties of PA. Since the cobalamin replacement therapy for PA is straightforward, it will not be discussed in this review.

The Clinical Applicability of Primary Thromboprophylaxis in Ambulatory Patients With Pancreatic Cancer.

ABSTRACT: Thromboembolism is a leading cause of death in ambulatory patients with cancer. Patients with pancreatic adenocarcinoma have a very high risk of developing venous thromboembolism, especially within the first 6 months of diagnosis. Although primary thromboprophylaxis could reduce this risk, there are unresolved questions concerning choice of agents for anticoagulation, duration of anticoagulation treatment, and criteria for patient selection. Furthermore, the current clinical guidelines on primary thromboprophylaxis in ambulatory patients with pancreatic cancer are ambiguous. This review seeks out to understand and critically appraise the evidence supporting the use of primary thromboprophylaxis in patients with pancreatic cancer and its clinical applicability.

Secondary erythrocytosis due to hemoglobin San Diego.

High-oxygen-affinity hemoglobin variants are a rare clinical entity that can present with secondary erythrocytosis. Herein, the author reports a case of a 41-year-old man with a 4-year history of secondary erythrocytosis of unknown etiology. Physical examination was unremarkable except for plethora of the palms. Myeloproliferative neoplasms and common causes of secondary erythrocytosis were ruled out. The P50 oxygen-hemoglobin dissociation curve was left shifted. Hemoglobin electrophoresis was silent; however, globin mass spectrometry revealed a ß-globin variant. Globin sequencing confirmed hemoglobin San Diego. This case highlights the fact that rare high-oxygen-affinity variants should be considered in the differential diagnoses of secondary erythrocytosis.