Prediction of venous thromboembolism in cancer patients

Cancer-associated venous thrombosis in adults (second edition): A British Society for Haematology Guideline

A shared decision on the most appropriate agent for the treatment of cancer-associated thrombosis should consider the following factors, which should be reassessed as patients continue along their cancer care pathway: risk of bleeding; tumour site; suitability of oral medications; potential for drug-drug interactions; and patient preference and values regarding choice of drug. Continuing anticoagulation beyond 6 months in patients with cancer-associated venous thromboembolism and active cancer is recommended.

Predicting VTE and utility of thromboprophylaxis in metastatic and recurrent cervical cancer

OBJECTIVE

Patients with cervical cancer who are diagnosed with venous thromboembolism (VTE) have worse outcomes compared to those not affected. There has yet to be a reliable method to predict or prevent VTE in cervical cancer patients. Our objective is to describe the incidence of VTE in patients with recurrent and metastatic (r/mCC) and determine risk factors that may predict VTE in this setting.

METHODS

We performed an observational cohort study of 386 patients with r/mCC who received at least one line of systemic chemotherapy. We collected demographic, clinical, histologic data and Khorana scores for all patients. Inclusion and exclusion criteria were applied before analysis. Statistical analysis was performed using Pearson chi-square, Student's t-test, and Wilcoxon rank-sum.

RESULTS

232 patients were included for evaluation. Mean age was 49 years (range 20-83). The majority (167, 72%) of patients had squamous cell histology. 169 (72.8%) patients received treatment for recurrent disease and 63 (27.2%) for metastatic, stage IVB disease. 180 (78%) patients received prior radiation and 134 (58%) received bevacizumab. VTE was diagnosed in 89 (38%) patients. There were no statistically significant differences amongst clinical and pathologic characteristics between patients who developed VTE and those who did not. There was no significant association between BMI, Khorana score, radiation, bevacizumab, or immunotherapy and the development of VTE.

CONCLUSION

Approximately 40% of patients with r/mCC experienced a new VTE. There were no independent risk factors that could predict VTE in this population. Due to the overwhelmingly high incidence of VTE, prophylactic anticoagulation could be strongly considered in patients with r/mCC.

Circulating Blood Biomarkers and Risk of Venous Thromboembolism in Cancer Patients: A Systematic Review and Meta-Analysis

BACKGROUND

 Cancer patients have an increased risk of venous thromboembolism (VTE). Currently, the availability of highly discriminatory prediction models for VTE in cancer patients is limited. The implementation of biomarkers in prediction models might lead to refined VTE risk prediction. In this systematic review and meta-analysis, we aimed to evaluate candidate biomarkers and their association with cancer-associated VTE.

METHODS

 We searched Medline, EMBASE, and Cochrane Central for studies that evaluated biomarkers in adult cancer patients from inception to September 2022. We included studies reporting on VTE after a cancer diagnosis with biomarker measurements performed at a defined time point. Median/mean differences (for continuous measures) and odds ratios (for dichotomous measures) with 95% confidence intervals were estimated and pooled using random-effects models.

RESULTS

 We included 113 studies in the systematic review. Of these, 50 studies were included in the meta-analysis. We identified two biomarkers at cancer diagnosis (factor VIII and time to peak thrombin), three biomarkers pre-chemotherapy (D-dimer, fibrinogen, and mean platelet volume), and one biomarker preoperatively (platelet count) that had significant median or mean differences. Additionally, we found that hemoglobin <100 g/L and white blood count >11 × 109/L were significantly associated with future VTE risk only when measured at cancer diagnosis. Pre-chemotherapy neutrophil-to-lymphocyte ratio ≥3 and preoperative platelet count ≥400 × 109/L were also found to be associated with future VTE risk.

CONCLUSION

 In conclusion, this study identified nine candidate blood biomarkers that may help in optimizing VTE prediction in cancer patients that should be further explored in future studies.

Predictive modeling of deep vein thrombosis risk in hospitalized patients: A Q-learning enhanced feature selection model

Deep vein thrombosis (DVT) represents a critical health concern due to its potential to lead to pulmonary embolism, a life-threatening complication. Early identification and prediction of DVT are crucial to prevent thromboembolic events and implement timely prophylactic measures in high-risk individuals. This study aims to examine the risk determinants associated with acute lower extremity DVT in hospitalized individuals. Additionally, it introduces an innovative approach by integrating Q-learning augmented colony predation search ant colony optimizer (QL-CPSACO) into the analysis. This algorithm, then combined with support vector machines (SVM), forms a bQL-CPSACO-SVM feature selection model dedicated to crafting a clinical risk prognostication model for DVT. The effectiveness of the proposed algorithm's optimization and the model's accuracy are assessed through experiments utilizing the CEC 2017 benchmark functions and predictive analyses on the DVT dataset. The experimental results reveal that the proposed model achieves an outstanding accuracy of 95.90% in predicting DVT. Key parameters such as D-dimer, normal plasma prothrombin time, prothrombin percentage activity, age, previously documented DVT, leukocyte count, and thrombocyte count demonstrate significant value in the prognostication of DVT. The proposed method provides a basis for risk assessment at the time of patient admission and offers substantial guidance to physicians in making therapeutic decisions.

Cancer-Associated Thrombosis: Pathophysiology, Laboratory Assessment, and Current Guidelines

Dysregulated hemostasis in cancer patients is associated with various clinical conditions, from thromboembolic complications to disseminated intravascular coagulation. Despite the well-established association between cancer and thromboembolic complications, the mechanisms involved are not completely elucidated. There are several predisposing factors in cancer for increased thrombus generation, such as immobilization and chemotherapy. The term cancer-associated thrombosis (CAT) has been introduced to describe the close bidirectional relationship between cancer and thromboembolic events. Conventional coagulation tests (PT/aPTT) are more accurate in detecting a hypocoagulable rather than a hypercoagulable state; thus, their contribution to CAT management is limited. Traditionally, D-dimer levels have been the most common laboratory study for the evaluation of thrombotic risk. However, D-dimer levels only display a snapshot of the coagulation cascade, and they cannot provide a dynamic evaluation of evolving clot formation. Non-conventional assays, such as viscoelastic methods and microparticle formation are promising tools for the identification of patients at risk for developing CAT. Recent guidelines from the American Society of Clinical Oncology counsel against the estimation of thrombotic risk through a single test and recommend the use of scoring systems that take into account several risk factors. The present review outlines the current insights into the pathophysiological mechanisms of CAT and provides a comprehensive review of the latest advances in the laboratory assessment of CAT and the recent guidelines for the management of patients at risk for developing thromboembolic complications.

Identifying novel biomarkers using proteomics to predict cancer-associated thrombosis

Comprehensive protein analyses of plasma are made possible by high-throughput proteomic screens, which may help find new therapeutic targets and diagnostic biomarkers. Patients with cancer are frequently affected by venous thromboembolism (VTE). The limited predictive accuracy of current VTE risk assessment tools highlights the need for new, more targeted biomarkers. Although coagulation biomarkers for the diagnosis, prognosis, and treatment of VTE have been investigated, none of them have the necessary clinical validation or diagnostic accuracy. Proteomics holds the potential to uncover new biomarkers and thrombotic pathways that impact the risk of thrombosis. This review explores the fundamental methods used in proteomics and focuses on particular biomarkers found in VTE and cancer-associated thrombosis.

Development of a chemiluminescence assay for tissue plasminogen activator inhibitor complex and its applicability to gastric cancer

BACKGROUND

Venous thromboembolism (VTE), is a noteworthy complication in individuals with gastric cancer, but the current diagnosis and treatment methods lack accuracy. In this study, we developed a t-PAIC chemiluminescence kit and employed chemiluminescence to detect the tissue plasminogen activator inhibitor complex (t-PAIC), thrombin-antithrombin III complex (TAT), plasmin-α2-plasmin inhibitor complex (PIC) and thrombomodulin (TM), combined with D-dimer and fibrin degradation products (FDP), to investigate their diagnostic potential for venous thrombosis in gastric cancer patients. The study assessed variations in six indicators among gastric cancer patients at different stages.

RESULTS

The t-PAIC reagent showed LOD is 1.2 ng/mL and a linear factor R greater than 0.99. The reagents demonstrated accurate results, with all accuracy deviations being within 5%. The intra-batch and inter-batch CVs for the t-PAIC reagent were both within 8%. The correlation coefficient R between this method and Sysmex was 0.979. Gastric cancer patients exhibited elevated levels of TAT, PIC, TM, D-D, FDP compared to the healthy population, while no significant difference was observed in t-PAIC. In the staging of gastric cancer, patients in III-IV stages exhibit higher levels of the six markers compared to those in I-II stages. The ROC curve indicates an enhancement in sensitivity and specificity of the combined diagnosis of four or six indicators.

CONCLUSION

Our chemiluminescence assay performs comparably to Sysmex's method and at a reduced cost. The use of multiple markers, including t-PAIC, TM, TAT, PIC, D-D, and FDP, is superior to the use of single markers for diagnosing VTE in patients with malignant tumors. Gastric cancer patients should be screened for the six markers to facilitate proactive prophylaxis, determine the most appropriate treatment timing, ameliorate their prognosis, decrease the occurrence of venous thrombosis and mortality, and extend their survival.

Advances and current research in primary thromboprophylaxis to prevent hospital-associated venous thromboembolism

Hospital-associated venous thromboembolism (VTE) is defined as any case of VTE occurring during hospital admission and for up to 90 days post discharge. It accounts for over 50% of all cases of VTE internationally; indeed, there are an estimated 10 million cases of hospital-associated VTE annually. Over the last decade, there has been increasing interest in improving VTE risk assessment and thromboprophylaxis. This review summarises all the recent and ongoing major research studies and future challenges in the different areas, including medical, surgical and obstetric patients, as well as special areas such as lower limb immobilisation. We include sections on both pharmacological and mechanical thromboprophylaxis.

The pathogenesis of cancer-associated thrombosis

Patients with cancer have a higher risk of venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), compared to the general population. Cancer-associated thrombosis (CAT) is a thrombotic event that occurs as a complication of cancer or cancer therapy. Major factors determining VTE risk in cancer patients include not only treatment history and patient characteristics, but also cancer type and site. Cancer types can be broadly divided into three groups based on VTE risk: high risk (pancreatic, ovarian, brain, stomach, gynecologic, and hematologic), intermediate risk (colon and lung), and low risk (breast and prostate). This implies that the mechanism of VTE differs between cancer types and that specific VTE pathways may exist for different cancer types. This review summarizes the specific pathways that contribute to VTE in cancer patients, with a particular focus on leukocytosis, neutrophil extracellular traps (NETs), tissue factor (TF), thrombocytosis, podoplanin (PDPN), plasminogen activator inhibitor-1 (PAI-1), the intrinsic coagulation pathway, and von Willebrand factor (VWF).

Clinical guidelines for prevention and treatment of CAT in Japan and other countries

Cancer-associated thrombosis (CAT) is an important prognostic factor for an increasing number of cancer patients. Understanding of CAT among cancer care providers has grown in recent years, and guidelines for the prevention and treatment of CAT have been published in Japan and around the world. In this article, we introduce these major guidelines and discuss differences we identified between the Japanese guidelines and those of other countries, with a focus on problems and issues. Insurance coverage of low-molecular-weight heparin and indications for primary prevention with direct oral anticoagulants in particular require urgent consideration.

The plasma miRNome and venous thromboembolism in high-grade glioma: miRNA Sequencing of a nested case-control cohort

Patients with high-grade gliomas are at high risk of venous thromboembolism (VTE). MicroRNAs (miRNAs) are small non-coding RNAs with multiple roles in tumour biology, haemostasis and platelet function. Their association with VTE risk in high-grade glioma has not been comprehensively mapped so far. We thus conducted a nested case-control study within 152 patients with WHO grade IV glioma that had been part of a prospective cohort study on VTE risk factors. At inclusion a single blood draw was taken, and patients were thereafter followed for a maximum of 2 years. During that time, 24 patients (16%) developed VTE. Of the other 128 patients, we randomly selected 24 age- and sex-matched controls. After quality control, the final group size was 21 patients with VTE during follow-up and 23 without VTE. Small RNA next-generation sequencing of plasma was performed. We observed that hsa-miR-451a was globally the most abundant miRNA. Notably, 51% of all miRNAs showed a correlation with platelet count. The analysis of miRNAs differentially regulated in VTE patients-with and without platelet adjustment-identified potential VTE biomarker candidates such as has-miR-221-3p. Therewith, we here provide one of the largest and deepest peripheral blood miRNA datasets of high-grade glioma patients so far, in which we identified first VTE biomarker candidates that can serve as the starting point for future research.

Risk of Venous Thromboembolism by Cancer Type: A Network Meta-Analysis

Patients with cancer have an increased risk of venous thromboembolism (VTE). Comparing tumor-specific VTE risk is complicated by factors such as surgery, disease stage, and chemotherapy. Network meta-analysis (NMA) using cancer types as network nodes enabled us to estimate VTE rates by leveraging comparisons across cancer types while adjusting for baseline VTE risk in individual studies. This study was conducted to estimate the risk of VTE by cancer type and factors influencing VTE risk. The Embase, MEDLINE, and Cochrane Library repositories were systematically searched to identify clinical trials and observational studies published from 2005 to 2022 that assessed the risk of primary cancer-related VTE among two or more distinct cancer types. Studies with similar cancer populations and study methods reporting VTE occurring within 1 year of diagnosis were included in the NMA. Relative VTE rates across cancer types were estimated with random-effects Bayesian NMAs. Absolute VTE rates were calculated from these estimates using the average VTE incidence in lung cancer (the most frequently reported type) as the "anchor." From 2,603 records reviewed, 30 studies were included in this NMA. The general network described 3,948,752 patients and 18 cancer types: 3.1% experienced VTE within 1 year of diagnosis, with cancer-specific rates ranging from 0.7 to 7.4%. Consistent with existing VTE risk prediction tools, pancreatic cancer was associated with higher-than-average VTE risk. Other cancer types with high VTE risk were brain and ovarian cancers. The relative rankings of VTE risk for certain cancers changed based on disease stage and/or receipt of chemotherapy or surgery.

Association of D-dimer level with thrombotic events, bleeding, and mortality in Japanese patients with solid tumors: a Cancer-VTE Registry subanalysis

BACKGROUND

The D-dimer test is a simple test frequently used in routine clinical screening for venous thromboembolism (VTE). The Cancer-VTE Registry was a large-scale, multicenter, prospective, observational study in Japanese patients with cancer. This study aimed to clarify the relationship between D-dimer level at cancer diagnosis (baseline) and the incidence of events during cancer treatment (1-year follow-up period).

METHODS

This was a post hoc sub-analysis of patients from the Cancer-VTE Registry whose D-dimer levels were measured at baseline. The incidence of events during the 1-year follow-up period was evaluated stratified by baseline D-dimer level. Adjusted hazard ratios for D-dimer level and events during the follow-up period were evaluated.

RESULTS

Among the total enrolled patients, baseline D-dimer level was measured in 9020 patients. The mean ± standard deviation baseline D-dimer level was 1.57 ± 3.94 µg/mL. During the follow-up period, the incidence of VTE, cerebral infarction/transient ischemic attack (TIA)/systemic embolic events (SEE), bleeding, and all-cause death increased with increasing baseline D-dimer level. The incidence of all-cause death increased with increasing D-dimer level regardless of cancer stage. The adjusted hazard ratio of all-cause death was 1.03 (95% confidence interval: 1.02-1.03) per 1.0-µg/mL increase in baseline D-dimer level.

CONCLUSIONS

Increases in D-dimer levels were associated with a higher risk of thrombotic events, such as VTE and cerebral infarction/TIA/SEE, during cancer treatment. Furthermore, higher D-dimer levels at cancer diagnosis were associated with a higher mortality rate, regardless of cancer stage.

Applications of Viscoelastic Testing in Breast Cancer Patients: A Systematic Review Focusing on Hypercoagulability and Free Flap Thrombosis

Viscoelastic testing is a clinically available method to assess hypercoagulability. This systematic review aims to provide a comprehensive overview of the existing literature and the potential use of such testing in patients with breast cancer. A systematic literature search for studies investigating the application of viscoelastic testing for patients with breast cancer was conducted. Studies were included as long as they were original, peer-reviewed, and in the English language. Studies were excluded if they were review articles, did not include breast cancer patients, or if the full text was unavailable. This review identified 10 articles that met the inclusion criteria. Two of the studies utilized rotational thromboelastometry, and an additional four studies used thromboelastography, to assess hypercoagulability in patients with breast cancer. Three of the identified articles discussed the use of thromboelastometry in free flap breast reconstruction for patients with breast cancer. One study was a retrospective chart review looking at thromboelastography and microsurgical breast reconstruction. Current literature regarding the application of viscoelastic testing in breast cancer and free flap breast reconstruction is limited, with no randomized trials thus far. However, some studies suggest that there may be potential utility in viscoelastic testing to assess risk for thromboembolism in breast cancer patients, and future research in this area is warranted.

Platelet Parameters as Biomarkers for Thrombosis Risk in Cancer: A Systematic Review and Meta-analysis

Cancer-associated thrombosis (CAT) is a major cause of both morbidity and mortality in cancer patients. Platelet count has been investigated as a predictor of CAT in various settings while knowledge on platelet activation parameters is sparse. This report provides a systematic review and meta-analysis on available literature on associations between platelet count and/or function and arterial and venous thrombosis in adult cancer patients. The review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. PubMed and Embase were searched up to March 2022. The National Heart, Lung, and Blood Institute's tools were used for quality assessment. In total, 100 studies were included which investigated the association between CAT and platelet count (n = 90), platelet indices (n = 19), and platelet function/activation markers (n = 13) in patients with solid cancers (n = 61), hematological cancers (n = 17), or mixed cancer types (n = 22). Eighty-one studies had venous thrombosis as their outcome measure, while 4 had arterial thrombosis and 15 studies had both. We found significantly elevated odds ratio of 1.50 (95% confidence interval: 1.19-1.88) for thrombosis with higher platelet counts. We saw a tendency toward an association between markers of platelet activation in forms of mean platelet volume and soluble P selectin and both arterial and venous thrombosis. Only one study investigated dynamic platelet function using flow cytometry. In conclusion, platelet count is associated with CAT across different cancer types and settings. Platelet function or activation marker analysis may be valuable in assisting thrombosis risk assessment in cancer patients but is sparsely investigated so far.

Thrombin Generation Markers as Predictors of Cancer-Associated Venous Thromboembolism: A Systematic Review

Venous thromboembolism (VTE) is a main contributor to morbidity and mortality in cancer patients. Biomarkers with the potential to predict cancer-associated VTE are continually sought. Of these, markers of thrombin generation present a likely option. The present systematic review examines the ability of three widely used biomarkers of thrombin generation: prothrombin fragment 1.2 (F1.2), thrombin-antithrombin complex (TAT), and ex vivo thrombin generation, to predict VTE in both solid and hematologic adult cancer patients. Relevant studies were identified in the PubMed and Embase databases, and the review conformed to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Each study was evaluated using the quality assessment tool from the National Heart, Lung, and Blood Institute. The review protocol was published on PROSPERO with identifier CRD42022362339. In total, 24 papers were included in the review: 11 reporting data on F1.2, 9 on TAT, and 12 on ex vivo thrombin generation. The quality ratings of the included studies varied from good (n = 13), fair (n = 8), to poor (n = 3) with a high heterogenicity. However, F1.2, TAT complex, and ex vivo thrombin generation were all found to be associated with the development of VTE. This association was most pronounced for F1.2. Furthermore, the determination of F1.2 was able to improve the precision of several established risk assessment scores. In conclusion, markers of thrombin generation were found to be elevated in cancer patients with VTE, and particularly, F1.2 was found to be a promising predictor of cancer-associated VTE.

The association of tumor-expressed REG4, SPINK4 and alpha-1 antitrypsin with cancer-associated thrombosis in colorectal cancer

Novel biomarkers are needed to improve current imperfect risk prediction models for cancer-associated thrombosis (CAT). We recently identified an RNA-sequencing profile that associates with CAT in colorectal cancer (CRC) patients, with REG4, SPINK4, and SERPINA1 as the top-3 upregulated genes at mRNA level. In the current study, we investigated whether protein expression of REG4, SPINK4 and alpha-1 antitrypsin (A1AT, encoded by SERPINA1) in the tumor associated with CAT in an independent cohort of CRC patients. From 418 patients with resected CRC, 18 patients who developed CAT were age, sex, and tumor stage-matched to 18 CRC patients without CAT. Protein expression was detected by immunohistochemical staining and scored blindly by assessing the H-score (percentage positive cells*scoring intensity). The association with CAT was assessed by means of logistic regression, using patients with an H-score below 33 as reference group. The odds ratios (ORs) for developing CAT for patients with A1AThigh, REG4high, SPINK4high tumors were 3.5 (95%CI 0.8-14.5), 2.0 (95%CI 0.5-7.6) and 2.0 (95%CI 0.5-7.4) when compared to A1ATlow, REG4low, SPINK4low, respectively. The OR was increased to 24.0 (95%CI 1.1-505.1) when two proteins were combined (A1AThigh/REG4high). This nested case-control study shows that combined protein expression of A1AT and REG4 associate with CAT in patients with colorectal cancer. Therefore, REG4/A1AT are potential biomarkers to improve the identification of patients with CRC who may benefit from thromboprophylaxis.

Models for predicting venous thromboembolism in ambulatory patients with lung cancer: A systematic review and meta-analysis

AIMS

The incidence of venous thromboembolism (VTE) in patients with lung cancer is relatively high, and risk stratification models are vital for the targeted application of thromboprophylaxis. We aimed to review VTE risk prediction models that have been developed in patients with lung cancer and evaluated their performance.

METHODS AND RESULTS

Twenty-four eligible studies involving 123,493 patients were included. The pooled incidence of VTE within 12 months was 11 % (95 % CI 8 %-14 %). With the identified four VTE risk assessment tools, meta-analyses did not show a significant discriminatory capability of stratifying VTE risk for Khorana, PROTECHT and CONKO scores. The pooled sensitivity and specificity of the Khorana score were 24 % (95 % CI 11 %-44 %) and 84 % (95 % CI 73 %-91 %) at the 3-point cut-off, and 43 % (95 % CI 35 %-52 %) and 61 % (95 % CI 52 %-69 %) at the 2-point cut-off. However, a COMPASS-CAT score of ≥ 7 points indicated a significantly high VTE risk, with a RR of 4.68 (95 % CI 1.05-20.80).

CONCLUSIONS

The Khorana score lacked discriminatory capability in identifying patients with lung cancer at high VTE risk, regardless of the cut-off value. The COMPASS-CAT score had better performance, but further validation is needed. The results indicate the need for robust VTE risk assessment tools specifically designed and validated for lung cancer patients. Future research should include relevant biomarkers as important predictors and consider the combined use of risk tools. PROSPERO registration number: CRD42021245907.

Developing a risk assessment tool for cancer-related venous thrombosis in China: a modified Delphi-analytic hierarchy process study

OBJECTIVE

To develop a Risk Assessment Tool for Cancer-related Venous Thrombosis in China.

METHODS

A modified two-round Delphi method was employed to establish consensus within a field to reach an agreement via a questionnaire or by interviewing a multidisciplinary panel of experts by collecting their feedback to inform the next round, exchanging their knowledge, experience, and opinions anonymously, and resolving uncertainties. Furthermore, The AHP (Analytic Hierarchy Process) was used to determine the final quality indicators' relative importance.

RESULTS

The expert's positive coefficient was 85.19% in the first round and 82.61% in the second round, with authoritative coefficients of 0.89 and 0.92 in the respective surveys. The P-value of Kendall's W test was all less than 0.001 for each round, and the W-value for concordance at the end of the two rounds was 0.115. The final Risk Assessment Tool for Cancer-related Venous Thrombosis consisted of three domains, ten subdomains, and 39 indicators, with patient factors weighing 0.1976, disease factors weighing 0.4905, and therapeutic factors weighing 0.3119.

CONCLUSION

The tool is significantly valid and reliable with a strong authority and coordination degree, and it can be used to assess the risk of cancer-related VTE and initiate appropriate thrombophylactic interventions in China.

Novel Insights in Venous Thromboembolism Risk Assessment Methods in Ambulatory Cancer Patients: From the Guidelines to Clinical Practice

Many cancer patients will experience venous thromboembolism (VTE) at some stage, with the highest rate in the initial period following diagnosis. Novel cancer therapies may further enhance the risk. VTE in a cancer setting is associated with poor prognostic, a decreased quality of life, and high healthcare costs. If thromboprophylaxis in hospitalized cancer patients and perioperative settings is widely accepted in clinical practice and supported by the guidelines, it is not the same situation in ambulatory cancer patient settings. The guidelines do not recommend primary thromboprophylaxis, except in high-risk cases. However, nowadays, risk stratification is still challenging, although many tools have been developed. The Khrorana score remains the most used method, but it has many limits. This narrative review aims to present the current relevant knowledge of VTE risk assessment in ambulatory cancer patients, starting from the guideline recommendations and continuing with the specific risk assessment methods and machine learning models approaches. Biomarkers, genetic, and clinical features were tested alone or in groups. Old and new models used in VTE risk assessment are exposed, underlining their clinical utility. Imaging and biomolecular approaches to VTE screening of outpatients with cancer are also presented, which could help clinical decisions.

The Application of Existing Risk Assessment Models (RAMS) to Predict the Occurrence of Venous Thromboembolic Events among Patients with Classic Hodgkin Lymphoma

Background: A majority of patients included in risk assessment models (RAMs) developed to predict venous thromboembolic events (VTE) in lymphoma were non-Hodgkin lymphoma. Our study aims to evaluate the incidence and predictors of VTE, utilizing different RAMs, in patients with classic Hodgkin lymphoma (cHL) treated with adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD). Methods: Adult patients with cHL, treated and followed at our center, were included. Correlations between different variables, Khorana score, and thrombosis in lymphoma (ThroLy) RAMs with VTE were examined using Fisher's exact test and logistic regression analysis. Results: A total of 321 patients were included, with a median age of 29 (range: 18-83) years. Of them, 169 (52.6%) had advanced-stage disease. Combined modality treatment was given to 169 (52.6%) patients. A total of 52 (16.2%) patients had relapsed or refractory disease. VTE were reported in 15 (4.7%) patients and were mostly during the administration of first-line (n = 8, 53.3%), or salvage chemotherapy (n = 6, 40.0%). There was no correlation between a Khorana score > 2 (p = 0.689) or ThroLy score > 3 (p = 0.335) and VTE. Older age (p = 0.014) and relapsed or refractory disease (p = 0.003) significantly correlated with VTE. Conclusions: VTE are uncommon in cHL. The commonly used RAMs failed to predict VTE. However, older age and relapsed or refractory disease significantly increased this risk.

Risk factors for peripherally inserted central catheter-related venous thrombosis in adult patients with cancer

PURPOSE

The purpose of this study was to understand and analyze the risk factors of peripherally inserted central catheter (PICC)-related venous thrombosis in adult patients with cancer.

METHODS

This observational cohort study included adult patients with cancer who underwent color Doppler ultrasound at the Xiangya Hospital of Central South University, Hunan Provincial Maternal and Child Healthcare Hospital, and Xiangya Changde Hospital, Hunan Province, from January 1, 2017 to December 31, 2021. Univariate and multivariate logistic regression analyses were performed to determine the risk factors of PICC-related venous thrombosis.

RESULTS

After risk adjustment, multivariate logistic regression analysis revealed statistically significant associations between PICC-related venous thrombosis and age > 65 years old (OR: 1.791, CI: 1.343-2.389), male sex (OR: 1.398, CI: 1.057-1.849), white blood cell count > 9.5 × 109 /L (OR: 1.422, CI: 1.041-1.942), APTT < 25 s (OR: 2.006, CI: 1.431-2.811), gastrointestinal tumor (OR: 2.191, CI: 1.406-3.414), infection (OR:7.619, CI: 5.783-10.037), the use of cisplatin (OR: 2.374, CI: 1.714-3.214), vincristine (OR: 2.329, CI: 1.447-3.749), the use of polyurethane (OR: 2.449, CI: 1.863-3.219) and open-ended catheters (OR:1.660, CI: 1.131-2.439), keeping time of the catheter (days) (OR: 1.003, CI: 1.001-1.005) were associated with PICC-related venous thrombosis.

CONCLUSION

We identified that the presence of age > 65 years old, male sex, white blood cell count > 9.5 × 109 /L, APTT < 25 s, gastrointestinal tumor, infection, the use of cisplatin and vincristine, the use of polyurethane, open-ended catheters and keeping time of the catheter (days), were associated with PICC-related venous thrombosis.

Cancer-associated thrombosis: What about microRNAs targeting the tissue factor coagulation pathway?

Cancer patients are often diagnosed with venous thromboembolism (VTE), a cardiovascular disease that substantially decreases their quality of life and survival rate. Haemostasis in these patients is deregulated, which is reflected in the common presentation of a blood hypercoagulation state. Despite the inconsistent results, existing evidence suggests that the expression of microRNAs (miRNAs) is deregulated in the context of venous thrombogenesis in the general population. However, few miRNAs are known to be linked to cancer-associated VTE due to the lack of studies with oncological patients. Parallelly, coagulation factor III, also known as tissue factor (TF), tissue factor pathway inhibitor 1 (TFPI1) and tissue factor pathway inhibitor 2 (TFPI2) have been proposed to have a central role in cancer-associated VTE and tumour progression. Yet, contrary to what was expected, the role of miRNAs targeting the TF coagulation pathway (or extrinsic coagulation pathway) is poorly explored in cancer-induced thrombogenesis. In this review, in addition to miRNAs implicated in VTE, TF and TFPI1/2-targeting miRNAs were revised. Future studies should clarify the implications of these non-coding RNAs in tumour coagulome.

A Predictive Model for Cancer-Associated Thrombosis in Japanese Cancer Patients: Findings from the J-Khorana Registry

Background  Although the close relationship between cancer and venous thromboembolism (VTE) has been identified, risk stratification for VTE in Japanese patients with cancer remains unclear. Objectives  This study aimed to validate the Khorana VTE risk assessment score (KRS) for VTE diagnosis and establish an optimal predictive model for VTE in Japanese patients with cancer. Methods  A total of 7,955 Japanese patients with cancer were subdivided into low- (0), intermediate- (1-2), and high-score (3) groups according to the KRS. Using 37 explanatory variables, a total of 2,833 patients with cancer were divided into derivation and validation cohorts (5:5). A risk model for Japanese participants was developed using the derivation cohort data. Results  The prevalence of VTE in low-, intermediate-, and high-score patients was 1.2, 2.5, and 4.3%, respectively. Logistic regression analysis demonstrated that cancer stage (III-IV) and KRS ≥ 2 were independent and significant predictors of VTE onset. The risk model for VTE assigned 1 point to body mass index ≥25 kg/m 2 and 2 points each to the prevalence of osteochondral cancer and D-dimer level ≥1.47 µg/mL. The areas under the curve of the risk model were 0.763 and 0.656 in the derivation and validation cohorts, respectively. Conclusion  The KRS was useful in Japanese patients, and our new predictive model may be helpful for the diagnosis of VTE in Japanese patients with cancer.

Cancer-Associated Thrombosis: Epidemiology, Pathophysiological Mechanisms, Treatment, and Risk Assessment

Cancer patients represent a growing population with drastically difficult care and a lowered quality of life, especially due to the heightened risk of vast complications. Thus, it is well established so far that one of the most prominent complications in individuals with cancer is venous thromboembolism. Since there are various improved methods for screening and diagnosing cancer and its complications, the incidence of cancer-associated thrombosis has been on the rise in recent years. Therefore, the high mortality and morbidity rates among these patients are not a surprise. Consequently, there is an excruciating need for understanding the mechanisms behind this complex process, as well as the imperative for adequate analysis and application of the most suitable steps for cancer-associated thrombosis prevention. There are various and numerous mechanisms offering potential answers to cancer-associated thrombosis, some of which have already been elucidated in various preclinical and clinical scenarios, yet further and more elaborate studies are crucial to understanding and preventing this complex and harsh clinical entity. This article elaborates on the growing incidence, mortality, morbidity, and risk factors of cancer-associated thrombosis while emphasizing the pathophysiological mechanisms in the light of various types of cancer in patients and summarizes the most novel therapy and prevention guidelines recommendations.

Comparison of risk prediction scores for cancer-associated thrombosis in ambulatory cancer patients not receiving thromboprophylaxis: A prospective cohort study in a South-East Asian population

INTRODUCTION

To date, there is limited data regarding the incidence and risk prediction of cancer-associated thrombosis among South-East Asian patients who do not receive thromboprophylaxis.

MATERIALS AND METHODS

This was a prospective cohort study conducted at a tertiary medical center from June 2020 to December 2021 in Thailand. We enrolled cancer patients aged ≥ 18 years, with ECOG score ≤ 1, scheduled to receive the first cycle of chemotherapy. We measured incidence of venous thromboembolism (VTE), all-cause mortality and performance of risk prediction scores.

RESULTS

A total of 457 patients were included with a mean age of 58.18 ± 12.60 years. By the end of 6 months period, VTE had occurred in 30 patients (6.56 %, 95%CI 4.36-9.21). The median time to the first thrombosis was 1.94 months (IQR 0.26-3.19). Cancer associated thrombosis incidence was 14.58 % for Khorana score ≥ 3, 6.67 % for scores 1-2 and 2.13 % for score 0. C-statistics were 0.50 (95%CI 0.41-0.60) for Khorana score cut-off ≥ 2, 0.57 (95%CI 0.49-0.65) for Khorana score ≥ 3, 0.55 (95%CI 0.46-0.65) for PROTECHT score ≥ 3, and 0.57 (95%CI 0.49-0.65) for CONKO score ≥ 3. Classifying cholangiocarcinoma as very-high-risk increased the Khorana score cut-off ≥ 3's C-statistic to 0.62 (95%CI 0.53-0.71).

CONCLUSIONS

A significant proportion of ambulatory South-East Asian cancer patients without thromboprophylaxis developed VTE. Further prospective studies investigating the benefit of thromboprophylaxis in high-risk patients with active cancer are warranted.

Development and Validation of a Modified Khorana Score for Predicting Venous Thromboembolism in Newly Diagnosed Stage IV Lung Cancer

We aimed to establish an effective model to identify metastatic lung cancer patients at high risk of venous thromboembolism (VTE). Patients diagnosed with stage IV lung cancer from January 2011 to June 2019 were included in the development cohort; those recruited from July 2019 to June 2021 were included in the validation cohort. Univariable and multivariable analyses determined the risk factors for VTE. Then we assessed the value for predicting VTE of the Khorana score and modified Khorana score in these two cohorts; 575 patients were included in the development cohort, and 202 patients in the validation cohort. Adenocarcinoma, D-dimer, and the Khorana score were independent risk factors for VTE. In the development cohort, the area under the receiver operating characteristic curve (AUC) of the Khorana score in patients with newly diagnosed stage IV lung cancer was 0.598 (95% CI, 0.512-0.684). The AUC of the modified Khorana score was 0.747 (95% CI, 0.689-0.805). The difference was statistically significant (P <.001). The AUC of the modified Khorana score in the validation cohort was 0.763 (95% CI, 0.661-0.865). The modified Khorana score is more able to accurately predict VTE in patients with newly diagnosed stage IV lung cancer than the Khorana score.

TIME-DEPENDENT CHANGES IN PROINFLAMMATORY MEDIATORS ARE ASSOCIATED WITH TRAUMA-RELATED VENOUS THROMBOEMBOLISM

ABSTRACT

Background: Tissue trauma and hemorrhage result in pronounced activation of the innate immune system. Given known crosstalk between inflammation and coagulation, soluble inflammatory mediators could be associated with venous thromboembolisms (VTEs) after major trauma. Objectives : This study aimed to identify plasma inflammatory mediators that are independent predictors of VTE risk in trauma patients. Methods: We performed a secondary analysis of the Pragmatic Randomized Optimal Platelets and Plasma Ratios (PROPPR) study. Plasma levels of 27 cytokines/chemokines were measured by Bio-Plex at admission and 2, 4, 6, 12, 24, 48, and 72 h later. Patients who died from exsanguination or within 24 h were excluded. Mann-Whitney tests were performed to assess no-VTE and VTE groups at each time point. Multivariable logistic regression was used to determine the adjusted effects of inflammatory mediators on VTE risk. Results: Eighty-six of the 575 patients (15%) included developed VTE. Interleukin (IL)-1ra, IL-6, IL-8, IL-10, eotaxin, granulocyte colony-stimulating factor, interferon-γ-inducible protein, monocyte chemoattractant protein 1 (MCP-1), and chemokine ligand 5 (regulated on activation, normal T cell expressed and secreted) were all significantly increased among VTE patients. Multivariable analyses demonstrated that IL-6, IL-8, interferon-γ-inducible protein, and MCP-1 were independently associated with VTE. Cox proportional hazards modeling identified IL-6, IL-8, and MCP-1 as independent predictors of accelerated VTE development. We identified significant correlations between inflammation and markers of coagulation and endothelial activation. Conclusion: Sustained systemic inflammation is a key driver of VTE risk after major trauma. Therapeutics targeting innate immune activation should be considered for development of future multimodal strategies to augment current VTE prophylaxis.

D-dimer predicts venous thromboembolism in multiple myeloma: a nested case-control study

Background

Clinical risk assessment scores, such as IMPEDE VTE, can identify patients with multiple myeloma (MM) at high-risk of venous thromboembolism (VTE). Refinement of these scores, by including 1 or more biomarkers, could improve risk assessment.

Objectives

We sought to determine the association between soluble P-selectin (sP-selectin) and D-dimer with VTE in MM.

Methods

We identified 545 patients with newly diagnosed MM. Using a nested case-control design, we identified 38 cases of VTE within 6-months of MM treatment and 137 randomly selected controls. Using logistic regression, we examined the association between D-dimer and sP-selectin with VTE. We also analyzed the association after adjusting for IMPEDE VTE.

Results

Each 1-point increase in IMPEDE VTE score was associated with a 27% increase in odds of VTE (odds ratio 1.27; 95% CI 1.08-1.51; c-statistic 0.61; 95% CI 0.51-0.71). There was no association between sP-selectin and VTE. Each one increase in natural log of D-dimer was associated with a 44% increase in odds of VTE, so we assigned points (ranging from -2 to +2) to D-dimer values and incorporated them into IMPEDE VTE, forming IMPEDED VTE. There was a 30% increase in odds of VTE per each 1-point increase in IMPEDED VTE (OR 1.30; 95% CI 1.12-1.52; c-statistic 0.65; 95% CI 0.55-0.75).

Conclusion

Among patients with newly diagnosed MM starting chemotherapy, D-dimer was associated with increased odds of developing VTE within the subsequent 6-months. The addition of D-dimer to IMPEDE VTE-IMPEDED VTE-could improve prediction of VTE among patients with MM.

Risk-Directed Ambulatory Thromboprophylaxis in Lung and Gastrointestinal Cancers: The TARGET-TP Randomized Clinical Trial

Importance

Thromboprophylaxis for individuals receiving systemic anticancer therapies has proven to be effective. Potential to maximize benefits relies on improved risk-directed strategies, but existing risk models underperform in cohorts with lung and gastrointestinal cancers.

Objective

To assess clinical benefits and safety of biomarker-driven thromboprophylaxis and to externally validate a biomarker thrombosis risk assessment model for individuals with lung and gastrointestinal cancers.

Design, Setting, and Participants

This open-label, phase 3 randomized clinical trial (Targeted Thromboprophylaxis in Ambulatory Patients Receiving Anticancer Therapies [TARGET-TP]) conducted from June 2018 to July 2021 (with 6-month primary follow-up) included adults aged 18 years or older commencing systemic anticancer therapies for lung or gastrointestinal cancers at 1 metropolitan and 4 regional hospitals in Australia. Thromboembolism risk assessment based on fibrinogen and d-dimer levels stratified individuals into low-risk (observation) and high-risk (randomized) cohorts.

Interventions

High-risk patients were randomized 1:1 to receive enoxaparin, 40 mg, subcutaneously daily for 90 days (extending up to 180 days according to ongoing risk) or no thromboprophylaxis (control).

Main Outcomes and Measures

The primary outcome was objectively confirmed thromboembolism at 180 days. Key secondary outcomes included bleeding, survival, and risk model validation.

Results

Of 782 eligible adults, 328 (42%) were enrolled in the trial (median age, 65 years [range, 30-88 years]; 176 male [54%]). Of these participants, 201 (61%) had gastrointestinal cancer, 127 (39%) had lung cancer, and 132 (40%) had metastatic disease; 200 (61%) were high risk (100 in each group), and 128 (39%) were low risk. In the high-risk cohort, thromboembolism occurred in 8 individuals randomized to enoxaparin (8%) and 23 control individuals (23%) (hazard ratio [HR], 0.31; 95% CI, 0.15-0.70; P = .005; number needed to treat, 6.7). Thromboembolism occurred in 10 low-risk individuals (8%) (high-risk control vs low risk: HR, 3.33; 95% CI, 1.58-6.99; P = .002). Risk model sensitivity was 70%, and specificity was 61%. The rate of major bleeding was low, occurring in 1 participant randomized to enoxaparin (1%), 2 in the high-risk control group (2%), and 3 in the low-risk group (2%) (P = .88). Six-month mortality was 13% in the enoxaparin group vs 26% in the high-risk control group (HR, 0.48; 95% CI, 0.24-0.93; P = .03) and 7% in the low-risk group (vs high-risk control: HR, 4.71; 95% CI, 2.13-10.42; P < .001).

Conclusions and Relevance

In this randomized clinical trial of individuals with lung and gastrointestinal cancers who were stratified by risk score according to thrombosis risk, risk-directed thromboprophylaxis reduced thromboembolism with a desirable number needed to treat, without safety concerns, and with reduced mortality. Individuals at low risk avoided unnecessary intervention. The findings suggest that biomarker-driven, risk-directed primary thromboprophylaxis is an appropriate approach in this population.

Trial Registration

ANZCTR Identifier: ACTRN12618000811202.

A nomogram for predicting the risk of venous thromboembolism in patients with solid cancers

Cancer patients with venous thromboembolism (VTE) are prone to poor prognoses. Thus, we aimed to develop a nomogram to predict the risk of VTE in these patients. We retrospectively analyzed 791 patients diagnosed with solid tumors between January 2017 and May 2021 at Tongji Hospital. Univariate logistic analysis and multivariate logistic regression were adopted in this study. Our results indicated that age ≥ 60 years, tumor stages III-IV, platelet distribution width (PDW) ≤ 12.6%, albumin concentration ≤ 38.8 g/L, lactate dehydrogenase (LDH) concentration ≥ 198 U/L, D-dimer concentration ≥ 1.72 µg/mL, blood hemoglobin concentration ≤ 100 g/dL or the use of erythropoiesis-stimulating agents and cancer types were independent risk factors. The nomogram prediction model was developed based on the regression coefficients of these variables. We assessed the performance of the nomogram by calibration plot and the area under the receiver operating characteristic curve and compared it with the Khorana score. The concordance index (C- index) of the nomogram was 0.852 [95% confidence interval (CI) 0.823 to 0.880], while the Khorana score was 0.681 (95% CI 0.639 to 0.723). Given its performance, this nomogram could be used to select cancer patients at high risk for VTE and guide thromboprophylaxis treatment in clinical practice, provided it is validated in an external cohort.

[Recommendations for thromboembolic disease in oncological processes. A view from primary care]

Venous thromboembolic disease (VTE) is a frequent complication in patients diagnosed with cancer and a cause of morbidity and mortality. Approximately 20% of thromboembolic episodes develop in association with active cancer. On the other hand, it is estimated that about 2-12% of cases, the thromboembolic episode is the first manifestation of an occult cancer, diagnosed at that time or subsequently, which offers an opportunity for early diagnosis and treatment. There are multiple factors that contribute to increase the risk of VTE in oncological patients in relation to specific characteristics of the patient, the tumor and the treatments. Knowledge of these risk factors will contribute to early diagnosis when signs of VTE appear, as well as the assessment of thromboprophylaxis if indicated. The diagnosis of VTE in patients with cancer does not differ of those who do not suffer from it. Regarding the treatment of VTE in these patients, low molecular weight heparin (LMWH), direct acting anticoagulants (DACs) and antivitamin K (VKA) are the most commonly used, although the dosing regimen and length are not clear yet. The management of these patients should be interdisciplinary and early, so the primary care physician plays a key role in this process as he/she is liaise with his/her patients. It is also necessary to update knowledge in order to improve the care of these patients. For these reasons, this document has been prepared by the Working Group on Vasculopathies of the Spanish Society of Primary Care Physicians (SEMERGEN) whose objective is to present the available information regarding the management of VTE that may appear in oncological patients, as well as the assessment of thromboprophylaxis and treatment, if appropriate, from an approach focused on a primary care field.

Prediction of Venous Thromboembolism in Patients With Cancer Using Machine Learning Approaches: A Systematic Review and Meta-Analysis

PURPOSE

Recent studies have suggested that machine learning (ML) could be used to predict venous thromboembolism (VTE) in cancer patients with high accuracy.

METHODS

We aimed to evaluate the performance of ML in predicting VTE events in patients with cancer. PubMed, Web of Science, and EMBASE to identify studies were searched.

RESULTS

Seven studies involving 12,249 patients with cancer were included. The combined results of the different ML models demonstrated good accuracy in the prediction of VTE. In the training set, the global pooled sensitivity was 0.87, the global pooled specificity was 0.87, and the AUC was 0.91, and in the test set 0.65, 0.84, and 0.80, respectively.

CONCLUSION

The prediction ML models showed good performance to predict VTE. External validation to determine the result's reproducibility is necessary.

Predicting venous thromboembolism (VTE) risk in cancer patients using machine learning

Background

The association between cancer and venous thromboembolism (VTE) is well-established with cancer patients accounting for approximately 20% of all VTE incidents. In this paper, we have performed a comparison of machine learning (ML) methods to traditional clinical scoring models for predicting the occurrence of VTE in a cancer patient population, identified important features (clinical biomarkers) for ML model predictions, and examined how different approaches to reducing the number of features used in the model impact model performance.

Methods

We have developed an ML pipeline including three separate feature selection processes and applied it to routine patient care data from the electronic health records of 1910 cancer patients at the University of California Davis Medical Center.

Results

Our ML-based prediction model achieved an area under the receiver operating characteristic curve of 0.778 ± 0.006 (mean ± SD) when trained on a set of 15 features. This result is comparable with the model performance when trained on all features in our feature pool [0.779 ± 0.006 (mean ± SD) with 29 features]. Our result surpasses the most validated clinical scoring system for VTE risk assessment in cancer patients by 16.1%. We additionally found cancer stage information to be a useful predictor after all performed feature selection processes despite not being used in existing score-based approaches.

Conclusion

From these findings, we observe that ML can offer new insights and a significant improvement over the most validated clinical VTE risk scoring systems in cancer patients. The results of this study also allowed us to draw insight into our feature pool and identify the features that could have the most utility in the context of developing an efficient ML classifier. While a model trained on our entire feature pool of 29 features significantly outperformed the traditionally used clinical scoring system, we were able to achieve an equivalent performance using a subset of only 15 features through strategic feature selection methods. These results are encouraging for potential applications of ML to predicting cancer-associated VTE in clinical settings such as in bedside decision support systems where feature availability may be limited.

Unmet clinical needs in the prevention and treatment of cancer-associated venous thromboembolism

Venous thromboembolism (VTE), which includes pulmonary embolism and deep vein thrombosis, is a leading cause of morbidity and mortality in patients with cancer. Based on accumulating evidence, the prophylaxis and treatment of cancer-associated VTE have been changed over the years. Recently, the introduction in clinical practice of the direct oral anticoagulants has radically changed the management of cancer-associated VTE for their easier use and non-inferior efficacy-safety profile compared to low-molecular-weight heparins. However, the heterogeneity of the cancer population in terms of site, type and stage of the malignancy, the presence of comorbidities, and the variability in cancer treatment and prognosis represent major challenges in the management of VTE in patients with cancer. In the present review, we will discuss clinical questions that represent unsolved issues in the setting of cancer-associated VTE and provide an overview on recent evidence on this topic: primary prophylaxis in ambulatory cancer patients treated with chemotherapy and in cancer surgical patients, need of long-term anticoagulation in cancer patients, treatment of VTE in cancer patients at increased bleeding risk and in special categories such as incidental VTE, splanchnic vein thrombosis or catheter-related thrombosis.

Utility of the Khorana and the new-Vienna CATS prediction scores in cancer patients of the HYPERCAN cohort

BACKGROUND

Risk assessment models (RAMs) are relevant approaches to identify cancer outpatients at high risk of venous thromboembolism (VTE). Among the proposed RAMs, the Khorana (KRS) and the new-Vienna CATS risk scores have been externally validated in ambulatory patients with cancer.

OBJECTIVES

To test KRS and new-Vienna CATS scores in 6-month VTE prediction and mortality in a large prospective cohort of metastatic cancer outpatients during chemotherapy.

PATIENTS/METHODS

Newly diagnosed patients with metastatic non-small cell lung, colorectal, gastric, or breast cancers were analyzed (n = 1286). The cumulative incidence of objectively confirmed VTE was estimated with death as a competing risk and multivariate Fine and Gray regression.

RESULTS

Within 6 months, 120 VTE events (9.7%) occurred. The KRS and the new-Vienna CATS scores showed comparable c-stat. Stratification by KRS provided VTE cumulative incidences of 6.2%, 11.4%, and 11.5% in the low-, intermediate-, and high-risk categories, respectively (p = ns), and of 8.5% vs. 11.8% (p = ns) in the low- vs. high-risk group by the single 2-point cut-off value stratification. Using a pre-defined 60-point cut-off by the new-Vienna CATS score, 6.6% and 12.2% cumulative incidences were obtained in the low- and high-risk groups, respectively (p < 0.001). Furthermore, having a KRS ≥2 = or a new-Vienna CATS score >60 points was also an independent risk factor for mortality.

CONCLUSION

In our cohort, the 2 RAMs showed a comparable discriminating potential; however, after the application of cut-off values, the new-Vienna CATS score provided statistically significant stratification for VTE. Both RAMs proved to be effective in identifying patients at increased risk of mortality.

Primary prevention of cancer-associated venous thrombosis: Rationale and challenges in clinical practice

Cancer-associated venous thrombosis (CAT) is a common, multifactor event known to complicate the course of cancer and jeopardize a patient's prognosis. The current guidelines regarding the prevention of CAT are sometimes considered insufficiently precise about specific situations, or are poorly applied. The expected benefits of thromboprophylaxis are balanced by the risk of major bleeding induced by anticoagulation, which implies a need to accurately identify ambulatory patients at high risk of thrombosis or hemorrhage. The Khorana score is commonly used for this, but is limited by the non-reproducibility of predicted performance across cancer types, and by the fact that antitumor treatment and cardiovascular risks are not included. The COMPASS-CAT score, which includes those two aspects, was found to be a more accurate predictor of venous thromboembolism in patients with lung cancer, and to better distinguish between patients at low or high risk of thrombosis. The frailty of patients with cancer is also a major issue, and should be taken into account when thromboprophylaxis is considered. According to current guidelines, CAT prophylaxis should be considered for hospitalized patients, those for whom surgery is scheduled, or those with pancreatic cancers. In ambulatory patients, decisions should be made according to patient, cancer and antitumoral treatment characteristics. Low molecular weight heparin is the gold standard of CAT prophylaxis. Despite increased risks of bleeding or drug-drug interactions in cancer patients, direct oral anticoagulants could be alternate options for high-risk ambulatory patients that should be accompanied by a careful global analysis of benefits, harms, and patient preferences.

Hemolysis, Elevated Liver Enzymes and Low Platelets (HELLP) Syndrome and Metastatic Breast Cancer: A Rare Overlap in a Postpartum Patient With Disseminated Intravascular Coagulation and Refractory Thrombocytopenia

A middle-aged female arrived at a tertiary care hospital after a referral from her primary care physician to evaluate a left breast mass found on ultrasound concerning malignancy. The patient was also 27 weeks gestational with monochorionic diamniotic twins. During triage, she was found to have severe hypertension and lab abnormalities concerning HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome and underwent cesarean delivery of the infants. She had a biopsy of the left breast mass post-delivery, later diagnosed as invasive ductal cell carcinoma with spinal metastasis and numerous metastatic pulmonary nodules. Her hospital stay was complicated by a right lower extremity deep vein thrombosis, acute subdural hematoma, and disseminated intravascular coagulation with refractory thrombocytopenia resulting in her death.

Application of the Khorana score for cancer-associated thrombosis prediction in patients of East Asian ethnicity undergoing ambulatory chemotherapy

BACKGROUND

The Khorana score (KS) has not been well studied in East Asian cancer patients, who have different genetic backgrounds for inherited thrombophilia, body metabolism, and cancer epidemiology.

METHODS

By using the Common Data Model, we retrospectively collected deidentified data from 11,714 consecutive newly diagnosed cancer patients who underwent first-line chemotherapy from December 2015 to December 2021 at a single institution in Korea, and we applied the KS for cancer-associated thrombosis (CAT) prediction. Age at diagnosis, sex, and use of highly thrombogenic chemotherapeutics were additionally investigated as potential risk factors for CAT development.

RESULTS

By 6 months after chemotherapy initiation, 207 patients (1.77%) experienced CAT. Only 0.4% had a body mass index (BMI) ≥ 35 kg/m² and changing the cutoff to 25 kg/m² improved the prediction of CAT. Age ≥ 65 years and the use of highly thrombogenic chemotherapeutics were independently associated with CAT development. KS values of 1 ~ 2 and ≥ 3 accounted for 52.3% and 7.6% of all patients, respectively, and the incidence of CAT in these groups was 2.16% and 4.16%, respectively, suggesting a lower incidence of CAT in the study population than in Westerners. The KS component regarding the site of cancer showed a good association with CAT development but needed some improvement.

CONCLUSION

The KS was partially validated to predict CAT in Korean cancer patients undergoing modern chemotherapy. Modifying the BMI cutoff, adding other risk variables, and refining the use of cancer-site data for CAT risk prediction may improve the performance of the KS for CAT prediction in East Asian patients.

Derivation and Validation of a Clinical Risk Assessment Model for Cancer-Associated Thrombosis in Two Unique US Health Care Systems

PURPOSE

Venous thromboembolism (VTE), especially pulmonary embolism (PE) and lower extremity deep vein thrombosis (LE-DVT), is a serious and potentially preventable complication for patients with cancer undergoing systemic therapy.

METHODS

Using retrospective data from patients diagnosed with incident cancer from 2011-2020, we derived a parsimonious risk assessment model (RAM) using least absolute shrinkage and selection operator regression from the Harris Health System (HHS, n = 9,769) and externally validated it using the Veterans Affairs (VA) health care system (n = 79,517). Bootstrapped c statistics and calibration curves were used to assess external model discrimination and fit. Dichotomized risk strata using integer scores were created and compared against the Khorana score (KS).

RESULTS

Incident VTE and PE/LE-DVT at 6 months occurred in 590 (6.2%) and 437 (4.6%) patients in HHS and 4,027 (5.1%) and 3,331 (4.2%) patients in the VA health care system. Assessed at the time of systemic therapy initiation, the new RAM included components of the KS with the modified cancer subtype, cancer staging, systemic therapy class, history of VTE, history of paralysis/immobility, recent hospitalization, and Asian/Pacific Islander race. The c statistic was 0.71 in HHS and 0.68 in the VA health care system (compared with 0.65 and 0.60, respectively, for KS). Furthermore, the new RAM appropriately reclassified 28% of patients and increased the proportion of VTEs in the high-risk group from 37% to 68% in the validation data set.

CONCLUSION

The novel RAM stratified patients with cancer into a high-risk group with 8%-10% cumulative incidence of VTE and 7% PE/LE-DVT at 6 months (v 3% and 2%, respectively, in the low-risk group). The model had improved performance over the original KS and doubled the number of VTE events in the high-risk stratum. We encourage additional external validation from prospective studies.[Media: see text].

Prevention of venous thromboembolism in patients with cancer

Venous thromboembolism (VTE) is a major cause of both morbidity and mortality in patients with cancer. Venous thromboembolism, which includes both deep vein thrombosis and pulmonary embolism, affects a sizable portion of patients with malignancy and can have potentially life threatening complications. Accurate assessment of risk as well as diagnosis and treatment of this process is paramount to preventing death in this high risk population. Various risk models predictive of venous thromboembolism in patients with cancer have been developed, and knowledge of these rubrics is essential for the treating oncologist. Subgroups of particular interest are inpatients receiving chemotherapy, postoperative patients after surgical debulking, and patients undergoing radiotherapy. Numerous newer drugs have become available for the prevention of venous thromboembolism in patients with cancer who are at high risk of developing the disease. These include the class of drugs called direct oral anticoagulants, (DOACs) which do not require the same monitoring that other modalities have previously required and are taken by mouth, preventing the discomfort associated with subcutaneous strategies. The appropriate risk stratification and intervention to prevent venous thromboembolism are vital to the treatment of patients with cancer.

Application of Machine Learning to the Prediction of Cancer-Associated Venous Thromboembolism

Venous thromboembolism (VTE) is a common and impactful complication of cancer. Several clinical prediction rules have been devised to estimate the risk of a thrombotic event in this patient population, however they are associated with limitations. We aimed to develop a predictive model of cancer-associated VTE using machine learning as a means to better integrate all available data, improve prediction accuracy and allow applicability regardless of timing for systemic therapy administration. A retrospective cohort was used to fit and validate the models, consisting of adult patients who had next generation sequencing performed on their solid tumor for the years 2014 to 2019. A deep learning survival model limited to demographic, cancer-specific, laboratory and pharmacological predictors was selected based on results from training data for 23,800 individuals and was evaluated on an internal validation set including 5,951 individuals, yielding a time-dependent concordance index of 0.72 (95% CI = 0.70-0.74) for the first 6 months of observation. Adapted models also performed well overall compared to the Khorana Score (KS) in two external cohorts of individuals starting systemic therapy; in an external validation set of 1,250 patients, the C-index was 0.71 (95% CI = 0.65-0.77) for the deep learning model vs 0.66 (95% CI = 0.59-0.72) for the KS and in a smaller external cohort of 358 patients the C-index was 0.59 (95% CI = 0.50-0.69) for the deep learning model vs 0.56 (95% CI = 0.48-0.64) for the KS. The proportions of patients accurately reclassified by the deep learning model were 25% and 26% respectively. In this large cohort of patients with a broad range of solid malignancies and at different phases of systemic therapy, the use of deep learning resulted in improved accuracy for VTE incidence predictions. Additional studies are needed to further assess the validity of this model.

Thrombosis and cachexia in cancer: two partners in crime?

Among cancer patients, thrombosis and cachexia are major causes of morbidity and mortality. Although the two may occur together, little is known about their possible relationship. Thus, a literature review was conducted by screening the databases PubMed, Scopus, SciELO, Medline and Web of Science. To summarize, cancer-associated thrombosis (CAT) and cancer-associated cachexia (CAC) seem to share several patient-, tumour- and treatment-related risk factors. Inflammation alongside metabolic and endocrine derangement is the potential missing link between CAT, CAC and cancer. Many key players, including specific pro-inflammatory cytokines, immune cells and hormones, appear to be implicated in both thrombosis and cachexia, representing attractive predictive markers and potential therapeutic targets. Altogether, the current evidence suggests a link between CAT and CAC, however, epidemiological studies are required to explore this potential relationship. Given the high incidence and negative impact of both diseases, further studies are needed for the better management of cancer patients.

Immune Checkpoint Inhibitors-Associated Thrombosis: Incidence, Risk Factors and Management

Immune checkpoint inhibitors (ICIs) target programmed cell death (PD) 1 receptor and its ligand PD-L1, and have become an integral part of treatment regimens in many cancers including lung cancer, renal cell carcinoma, melanoma, and more. Cancer is associated with a significantly increased risk of venous thromboembolism compared to non-cancer patients, and the risks increase further with anticancer therapies including ICIs. Cancer-associated thrombosis can lead to hospitalizations, delayed cancer treatment, and mortality. While thrombosis was not reported as a major complication in initial clinical trials leading to the approval of ICIs, emerging evidence from post-marketing studies revealed concerning risks of thrombosis in patients receiving ICIs. However, results remained heterogenous given differences in study designs and populations. Recent studies also showed that C-reactive protein dynamics might be an easily accessible biomarker for thrombosis and disease response in this population. In addition, early findings indicated that a commonly used anticoagulant for cancer-associated thrombosis, factor Xa inhibitors, might have potential synergistic antitumor effects when combined with ICIs. Herein we will review the current literature on the incidence, risk factors, and management of thrombosis in patients with cancer receiving ICIs. We aim to provide valuable information for clinicians in managing these patients.

Characteristics and Outcomes of Cancer Patients With Venous Thromboembolic Events After Treatment With Immune Checkpoint Inhibitors

OBJECTIVE

This study aimed to describe the clinical characteristics and outcomes of patients with venous thromboembolism (VTE) after Immune checkpoint inhibitors (ICI), focusing on patients with gastrointestinal (GI) immune-related adverse events (irAE).

METHODS

In this retrospective, single-center study, we report the clinical outcomes of adult cancer patients who developed a VTE within 2 years of ICI initiation. Patients were excluded if alternate causes of VTE were present apart from malignancy and cancer therapy. The cohort was classified into those with GI-irAE, non-GI-irAE, and no irAE. A control group with ICI exposure without irAE and VTE was selected for comparative analysis.

RESULTS

Of all ICI-treated patients, 1891 (17.2%) were diagnosed with VTE. In all, 501 (4.6%) had no etiology for VTE aside from malignancy and cancer therapy. Of these, 137 patients were included and classified as: 44 GI-irAE, 42 non-GI-irAE, and 51 no irAE. Chemotherapy within 6 months of ICI therapy was associated with increased VTE risk. There was no difference in the clinical course between those exposed to chemotherapy versus ICI therapy alone, time from ICI initiation to VTE, and VTE type, recurrence, or related hospitalization. While there was no difference in VTE-related mortality, the GI-irAE group was associated with lower all-cause mortality and superior overall survival.

CONCLUSION

Combined ICI and chemotherapy use increased VTE risk. There is a similar disease course of VTE after ICI exposure, regardless of other irAEs. Co-existing GI-irAE with VTE is associated with superior overall survival. Prospective studies are needed to evaluate the relationship between ICI therapy and VTE and irAE impact on VTE outcomes.

Using machine learning to predict venous thromboembolism and major bleeding events following total joint arthroplasty

Venous thromboembolism (VTE) and major bleeding (MBE) are feared complications that are influenced by numerous host and surgical related factors. Using machine learning on contemporary data, our aim was to develop and validate a practical, easy-to-use algorithm to predict risk for VTE and MBE following total joint arthroplasty (TJA). This was a single institutional study of 35,963 primary and revision total hip (THA) and knee arthroplasty (TKA) patients operated between 2009 and 2020. Fifty-six variables related to demographics, comorbidities, operative factors as well as chemoprophylaxis were included in the analysis. The cohort was divided to training (70%) and test (30%) sets. Four machine learning models were developed for each of the outcomes assessed (VTE and MBE). Models were created for all VTE grouped together as well as for pulmonary emboli (PE) and deep vein thrombosis (DVT) individually to examine the need for distinct algorithms. For each outcome, the model that best performed using repeated cross validation was chosen for algorithm development, and predicted versus observed incidences were evaluated. Of the 35,963 patients included, 308 (0.86%) developed VTE (170 PE's, 176 DVT's) and 293 (0.81%) developed MBE. Separate models were created for PE and DVT as they were found to outperform the prediction of VTE. Gradient boosting trees had the highest performance for both PE (AUC-ROC 0.774 [SD 0.055]) and DVT (AUC-ROC 0.759 [SD 0.039]). For MBE, least absolute shrinkage and selection operator (Lasso) analysis had the highest AUC (AUC-ROC 0.803 [SD 0.035]). An algorithm that provides the probability for PE, DVT and MBE for each specific patient was created. All 3 algorithms had good discriminatory capability and cross-validation showed similar probabilities comparing predicted and observed failures indicating high accuracy of the model. We successfully developed and validated an easy-to-use algorithm that accurately predicts VTE and MBE following TJA. This tool can be used in every-day clinical decision making and patient counseling.

Risk of venous thromboembolism and bleeding after major surgery for ovarian cancer: standard in-hospital versus extended duration of thromboprophylaxis

BACKGROUND

Venous thromboembolism (VTE) is a frequent complication in patients with ovarian cancer after major surgery. Based on limited data, international guidelines recommend extended thromboprophylaxis for up to 28 days.

OBJECTIVES

To assess the incidence of VTE and bleeding within 30 days following major surgery in patients with ovarian cancer and to evaluate the association between VTE and thromboprophylaxis duration.

METHODS

This was a single-center, retrospective, "before-after" cohort study in patients with ovarian cancer undergoing major surgery. Before July 2019, the local protocol mandated a standard course of thromboprophylaxis during hospital stay only. From July 2019 onward, patients received extended thromboprophylaxis for 28 days. The cumulative incidences of VTE and major bleeding within 30 days after surgery were estimated using the Kaplan-Meier method, with 95% confidence intervals (CIs). Cox regression analysis was performed to evaluate the association between thromboprophylaxis duration and VTE incidence.

RESULTS

Between January 2018 and December 2020, 250 women were included, of which 118 (47.2%) received extended and 132 (52.8%) standard thromboprophylaxis. During follow-up, 12 patients developed VTE (cumulative incidence, 4.8%; 95% CI, 2.1-7.4) and 2 major bleeding (cumulative incidence 0.8%; 95% CI, 0.0-1.9). Compared with standard thromboprophylaxis, VTE incidence was numerically lower with extended duration of thromboprophylaxis (5/118 [4.2%] vs 7/132 [5.3%]) but not significantly different (hazard ratio, 0.80; 95% CI, 0.25-2.52). The risk of major bleeding was similar in both groups (1/118 [0.8%] vs 1/132 [0.8%]; hazard ratio, 1.12; 95% CI, 0.07-17.89).

CONCLUSIONS

The cumulative VTE incidence in patients with ovarian cancer following major surgery was considerable. Extended thromboprophylaxis was safe and associated with a numerically lower risk of VTE but not significantly different.