Hemostatic Biomarkers and Venous Thromboembolism Are Associated With Mortality and Response to Chemotherapy in Patients With Pancreatic Cancer

Objective: Pancreatic cancer activates coagulation and increases risk of venous thromboembolism (VTE). We aimed at characterizing the association of hemostatic biomarkers and VTE with mortality and chemotherapy response. Approach and Results: Pancreatic cancer patients (n=145) were included in a prospective, observational cohort study (CATS [Vienna Cancer and Thrombosis Study]). Hemostatic biomarkers (D-dimer, extracellular vesicle–tissue factor activity, prothrombin fragment 1+2, fibrinogen, factor VIII, PAI-1 [plasminogen activator inhibitor 1], sP-selectin [soluble P-selectin], thrombin generation assay) were measured at inclusion. The impact of VTE on overall survival/progression-free survival (OS/PFS) was evaluated by multistate modeling. The association of biomarkers with OS was analyzed by Cox-regression and with PFS and disease control rate in patients initiating palliative chemotherapy (n=95) by Cox-regression and logistic regression. Multivariable analysis included stage, grade, sex, age, performance status, VTE (time-dependent), vascular infiltration/compression, and tumor marker levels (carbohydrate-antigen 19-9, carcinoembryonic antigen). VTE occurrence was associated with shorter OS (transition hazard ratio, 3.40 [95% CI, 2.05–5.64]) and shorter PFS (transition hazard ratio, 2.10 [1.16–3.79]). Median post-VTE OS/PFS in months was 5.5 [2.2–6.5] and 3.0 [1.5–3.9], compared with 13.4 [9.7–16.6] and 7.5 [5.9–9.8] in patients without VTE (both P <0.001). D-dimer, extracellular vesicle–tissue factor activity, PAI-1, and sP-selectin were associated with increased mortality (hazard ratio per doubling, 1.27 [1.00–1.61]; 1.63 [1.14–2.36]; 1.25 [1.06–1.47]; 1.52 [1.05–2.20]). In patients initiating palliative chemotherapy, higher D-dimer predicted shorter PFS (hazard ratio per doubling, 1.27 [1.01–1.60]) and lower disease control rate (odds ratio per doubling, 0.59 [0.36–0.98]). Conclusions: VTE diagnosis is associated with shorter OS and PFS. Higher baseline levels of D-dimer, extracellular vesicle–tissue factor activity, PAI-1, and sP-selectin were independently prognostic for increased mortality, and D-dimer predicted response to palliative chemotherapy.

Association of high level of plasma tissue factor activity with venous thromboembolism and early death in lung cancers.

8532 Background: Venous thromboembolism (VTE) is associated with tumor aggressiveness and mortality in cancers. Tissue Factor is the main activator of the coagulation but its variations in lung cancers (LC) have been less studied than D-dimers (DDi). We assessed plasma Tissue Factor Activity (TFa) and DDi and VTE events and mortality in patients with LC. Methods: This prospective study included patients, from 5 hospitals, recently diagnosed LC, without prior VTE or anticoagulant therapy within the last 2 months. Clinical and tumor data, Khorana score (KS), VTE events and overall survival (OS) were assessed (follow up 2 years). Blood samples were collected before any cancer treatment (V1): DDi (HemosIL) and TFa (chromogenic assay, Diagnostica Stago) were analyzed in a central lab. Independent nonparametric tests were used for group comparisons. A relevant clinical threshold of both markers was determined :1500 μg/ml for DDi and 1.2 ng/ml for TFa. Early death was compared using Cox model and Kaplan Meier curves and logrank tests. All tests were two-tailed tests and 0.05 was considered as significant. Results: Between 12/2014 and 01/2017, 302 consecutive patients (pts) were included (mean age 64 years, 61% males, 89% smokers, 85% NSCLC, 67% stage IV). At V1, TFa levels increased with cancer stage (p = 0.004) but not DDi. VTE incidence was 13,9%: 39 events (62% incidental and 51% pulmonary embolism) with 33 events within 6 months. KS failed to predict VTE (KS > 3 in 23% of the pts in VTE group vs 21% of the 302 pts, p = 0.42). DDi and TFa levels were not significantly different in VTE pts than in no VTE pts. But, a TFa > 1.2 ng/ml was significantly predictive in occurrence of VTE within the first 6 months (57.6% of the VTE pts vs 38.8% of no VTE pts, p = 0.04), and also within the first year (p = 0.03). Median OS was 17,6 months (m) in VTE pts and 19.5 m in no VTE pts (p = 0,97). Compared to survivors, higher levels of DDi and TFa were observed for the 38 pts who died within 6 months : 1.82 vs 0.67 μg/ml (p < 0.001) and 1.95 vs 0.33 ng/ml (p < 0.001) respectively. These differences were observed for the 97 pts who died during the first year, too. With thresholds of TFa > 1.2 ng/ml and DDi > 1500 μg/ml, median OS was significantly shorter: 14.4 m vs > 29.8 m ( p < 0,001) and 13.8 m vs 22.6 m (p < 0.001), respectively. Conclusions: High TFa level discriminates a population with high risk to VTE and early death in LC. This biomarker could take place in a predictive score. Clinical trial information: NCT02853188.

Patients With COVID-19 Have Elevated Levels of Circulating Extracellular Vesicle Tissue Factor Activity That Is Associated With Severity and Mortality

Objective: Patients with coronavirus disease 2019 (COVID-19) have a high rate of thrombosis. We hypothesized that severe acute respiratory syndrome coronavirus 2 leads to induction of TF (tissue factor) expression and increased levels of circulating TF-positive extracellular vesicles (EV) that may drive thrombosis. Approach and Results: We measured levels of plasma EV TF activity in 100 patients with COVID-19 with moderate and severe disease and 28 healthy controls. Levels of EV TF activity were significantly higher in patients with COVID-19 compared with controls. In addition, levels of EV TF activity were associated with disease severity and mortality. Finally, levels of EV TF activity correlated with several plasma markers, including D-dimer, which has been shown to be associated with thrombosis in patients with COVID-19. Conclusions: Our results indicate that severe acute respiratory syndrome coronavirus 2 infection induces the release of TF-positive EVs into the circulation that are likely to contribute to thrombosis in patients with COVID-19. EV TF activity was also associated with severity and mortality.

Circulating Extracellular Vesicle Tissue Factor Activity in Chuvash Erythrocytosis

Background:Chuvash erythrocytosis (CE), an inherited autosomal recessive disease endemic to Russia's mid-Volga River region, is caused by a germlineVHLC598T mutation (encoding VHLR200W) that alters oxygen sensing (PMID: 12415268). VHLR200W protein displays impaired degradation of hypoxia inducible transcription factor (HIF)-α subunits leading to increased HIF-1 and HIF-2 in normoxia and increased transcription of many HIF-regulated genes including erythropoietin (PMID: 14726398). CE patients have increased risk of venous and arterial thromboses, which are the major cause of morbidity and mortality (PMID:28104701). Thrombosis occurs despite lower blood pressure, body mass index and white blood cells compared to controls and is not related to the elevation in hematocrit but is increased in patients treated with phlebotomy therapy (PMID: 31289208). We have shown by microarray analysis of CE peripheral blood mononuclear cells modestly increased expression of several HIF-regulated pro-thrombotic genes at false discovery rate &lt;0.05, includingIL1B(encoding interleukin-1beta),THBS1(thrombospondin-1),EGR1(early growth response 1),NLRP3,ITGA2B(integrin alpha-IIb),SERPINE1(plasminogen activator inhibitor-1) andF3(tissue factor) (PMID: 23993337). TF is a primary initiator of coagulation that binds factor VII/VIIa. The TF/factor VIIa complex catalyzes the conversion of inactive protease factor X to active protease factor Xa, leading to thrombin and thrombus formation (PMID: 19923557). EV-TF is barely detectable under basal circumstances but in disease states such as cardiovascular disease, sickle cell disease and cancer it derives from monocytes, endothelial cells, vascular smooth muscle cells and tumor cells (PMIDs: 20690821, 12805058, 17166244, 14988149, 26916302). Granulocytes of patients with polycythemia vera and essential thrombocytopenia expressF3as assessed by RT-qPCR (PMID: 32203583). Because of the central role of tissue factor in initiating the extrinsic pathway of coagulation, we set up to determine if extracellular vesicle associated tissue factor activity (EV-TF) could be detected in the plasma of CE patients. Methods:EightVHLC598T homozygotes and 6VHLwild type controls from Cheboksary, Chuvashia, Russia were studied as outpatients under basal circumstances. Blood was collected from these participants by venipuncture into vacutainer tubes containing 0.129 M sodium citrate. Immediately after venipuncture, platelet free plasma (PFP) was prepared by two rounds of centrifugation at 2,500 × g for 15 minutes at room temperature and EVs were isolated from PFP by centrifugation at 20,000 g for 15 minutes at 4 ºC. EV-TF was measured in duplicate by a two-stage Factor Xa generation assay with and without anti-TF antibody using Innovin (Siemens Healthcare Diagnostics) as a standard (PMID: 30656275). We also isolated granulocyte mRNA from 3 of the patients and 2 of the controls at a different time point and measured F3 transcripts by RT-qPCR. Results:We detected EV-TF in 4 of 8 CE patients but in no wild type controls (one-sided P = 0.043). The range of 0.45 to 1.25 pg/ml is similar to the range recently reported in US patients with cancer (PMID: 32548563). MCHC tended to be lower among 4 CE patients with detectable EV-TF than 4 without (one-sided P = 0.12), but this was not the case for serum ferritin. We also detectedF3transcripts in granulocytes, and these levels were higher in the 3 patients than the 2 controls that we analyzed (one-sided P = 0.12). Furthermore,F3mRNA correlated with plasma EV-TF in these five subjects (Spearman rho = 0.71, one-sided P &lt; 0.05). As previously reported, CE patients had higher hemoglobin, hematocrit and red blood cells and lower platelets compared to controls (PMID: 14726398). They also had lower values for serum ferritin and mean corpuscular hemoglobin concentration (MCHC) suggesting iron deficiency, likely induced by phlebotomy therapy or by the presence of gastritis, which is increased in CE. Discussion:The presence of EV-TF in the plasma of 4 out of 8 CE patients and none of six controls, and increasedF3transcripts in CE granulocytes, may point to a potential thrombogenic role, although none of the CE patients in this study had a history of thrombosis. Further studies on larger numbers of patients are warranted to confirm these findings and to clarify the potential role of EV-TF in thrombosis in CE. *NM, JTP & VRG contributed equally Figure Disclosures Gordeuk: CSL Behring:Consultancy, Research Funding;Ironwood:Research Funding;Imara:Research Funding;Global Blood Therapeutics:Consultancy, Research Funding;Novartis:Consultancy.