Differences in Tumor-Associated T cell receptor repertoires between Early-Onset and Average-Onset colorectal cancer.

The incidence of colorectal cancer (CRC) among individuals younger than age 50 (early onset CRC; EOCRC) has substantially increased, yet the etiology and molecular mechanisms underlying this alarming rise remain unclear. We compared tumor-associated T cell repertoires between EOCRC and average-onset CRC (AOCRC) to uncover potentially unique immune microenvironment-related features by age of onset. Our discovery cohort included 242 patients who underwent surgical resection at Cleveland Clinic from 2000 to 2020. EOCRC was defined as age < 50 years at diagnosis (N = 126), and AOCRC as age ≥ 60 years (N = 116). T cell receptor (TCR) abundance and clonality were measured by immunosequencing of tumors. Logistic regression models were used to evaluate the associations between TCR repertoire features and age of onset, adjusting for sex, race, tumor location, and stage. Findings were replicated in 152 EOCRC and 1,984 AOCRC cases from the Molecular Epidemiology of Colorectal Cancer Study. EOCRC tumors had significantly higher TCR diversity compared to AOCRC tumors in the discovery cohort (Odds Ratio (OR):0.44, 95% Confidence Interval (CI):0.32-0.61, p < .0001). This association was also observed in the replication cohort (OR : 0.74, 95% CI : 0.62-0.89, p = .0013). No significant differences in TCR abundance were observed between EOCRC and AOCRC in either cohort. Higher TCR diversity, suggesting a more diverse intratumoral T cell response, is more frequently observed in EOCRC than AOCRC. Further studies are warranted to investigate the role of T cell diversity and the adaptive immune response more broadly in the etiology and outcomes of EOCRC.

Comparison of rivaroxaban and low molecular weight heparin in the treatment of cancer-associated venous thromboembolism: a Swedish national population-based register study.

BACKGROUND: Treating cancer-associated venous thromboembolism (CAT) with anticoagulation prevents recurrent venous thromboembolism (rVTE), but increases bleeding risk. OBJECTIVES: To compare incidence of rVTE, major bleeding, and all-cause mortality for rivaroxaban versus low molecular weight heparin (LMWH) in patients with CAT. METHODS: We developed a cohort study using Swedish national registers 2013-2019. Patients with CAT (venous thromboembolism within 6 months of cancer diagnosis) were included. Those with other indications or with high bleeding risk cancers were excluded (according to guidelines). Follow-up was from index-CAT until outcome, death, emigration, or end of study. Incidence rates (IR) per 1000 person-years with 95% confidence interval (CI) and propensity score overlap-weighted hazard ratios (HRs) for rivaroxaban versus LMWH were estimated. RESULTS: We included 283 patients on rivaroxaban and 5181 on LMWH. The IR for rVTE was 68.7 (95% CI 40.0-109.9) for rivaroxaban, compared with 91.6 (95% CI 81.9-102.0) for LMWH, with adjusted HR 0.77 (95% CI 0.43-1.35). The IR for major bleeding was 23.5 (95% CI 8.6-51.1) for rivaroxaban versus 49.2 (95% CI 42.3-56.9) for LMWH, with adjusted HR 0.62 (95% CI 0.26-1.49). The IR for all-cause mortality was 146.8 (95% CI 103.9-201.5) for rivaroxaban and 565.6 (95% CI 541.8-590.2) for LMWH with adjusted HR 0.48 (95% CI 0.34-0.67). CONCLUSIONS: Rivaroxaban performed similarly to LMWH for patients with CAT for rVTE and major bleeding. An all-cause mortality benefit was observed for rivaroxaban which potentially may be attributed to residual confounding. TRIAL REGISTRATION NUMBER: NCT05150938 (Registered 9 December 2021).

Primary thromboprophylaxis in cancer outpatients - real-world evidence.

INTRODUCTION: Cancer-associated thrombosis (CAT) is a significant concern among patients with malignant diseases, leading to increased mortality. While current guidelines recommend primary thromboprophylaxis for venous thromboembolism (VTE) in medium-to-high-risk outpatients, this practice remains controversial. A better understanding of primary thromboprophylaxis is crucial, yet there is a lack of Real-World Evidence (RWE) in Portugal. AIMS: This RWE study aimed to elucidate primary thromboprophylaxis practices among cancer outpatients in Portugal. METHODS: A five-year observational multicentric study in eight Portuguese health institutions enrolled 124 adult cancer outpatients under primary thromboprophylaxis for VTE. The endpoints were CAT, bleeding, cancer progression and death. RESULTS: High thrombotic risk tumours were prevalent, with 57% (71) of the patients presenting with pancreatic and gastric cancers. Regarding primary thromboprophylaxis, 55% (68) received Low-Molecular-Weight Heparin (LMWH). VTE was presented in 11% (14) of the patients and major bleeding in 2% (2). Vascular compression, elevated D-dimer and previous VTE were significantly associated with VTE occurrence under primary thromboprophylaxis. The Onkotev model was shown to be the best risk assessment model (RAM) in this population (p = 0.007). CAT patients exhibited a lower progression-free survival than non-CAT patients (p = 0.021), while thrombosis did not influence overall survival (p = 0.542). CONCLUSION: Primary thromboprophylaxis in medium-to-high-risk cancer outpatients is a safe and effective practice in real-world settings. This study is the first Portuguese RWE on primary thromboprophylaxis, highlighting evidence for improving prophylactic strategies in this population.

Plasma metabolomic differences in early-onset compared to average-onset colorectal cancer.

Deleterious effects of environmental exposures may contribute to the rising incidence of early-onset colorectal cancer (eoCRC). We assessed the metabolomic differences between patients with eoCRC, average-onset CRC (aoCRC), and non-CRC controls, to understand pathogenic mechanisms. Patients with stage I-IV CRC and non-CRC controls were categorized based on age ≤ 50 years (eoCRC or young non-CRC controls) or  ≥ 60 years (aoCRC or older non-CRC controls). Differential metabolite abundance and metabolic pathway analyses were performed on plasma samples. Multivariate Cox proportional hazards modeling was used for survival analyses. All P values were adjusted for multiple testing (false discovery rate, FDR P < 0.15 considered significant). The study population comprised 170 patients with CRC (66 eoCRC and 104 aoCRC) and 49 non-CRC controls (34 young and 15 older). Citrate was differentially abundant in aoCRC vs. eoCRC in adjusted analysis (Odds Ratio = 21.8, FDR P = 0.04). Metabolic pathways altered in patients with aoCRC versus eoCRC included arginine biosynthesis, FDR P = 0.02; glyoxylate and dicarboxylate metabolism, FDR P = 0.005; citrate cycle, FDR P = 0.04; alanine, aspartate, and glutamate metabolism, FDR P = 0.01; glycine, serine, and threonine metabolism, FDR P = 0.14; and amino-acid t-RNA biosynthesis, FDR P = 0.01. 4-hydroxyhippuric acid was significantly associated with overall survival in all patients with CRC (Hazards ratio, HR = 0.4, 95% CI 0.3-0.7, FDR P = 0.05). We identified several unique metabolic alterations, particularly the significant differential abundance of citrate in aoCRC versus eoCRC. Arginine biosynthesis was the most enriched by the differentially altered metabolites. The findings hold promise in developing strategies for early detection and novel therapies.

Dysregulated platelet function in patients with postacute sequelae of COVID-19.

BACKGROUND: Postacute sequelae of COVID-19 (PASC), also referred to as "Long COVID", sometimes follows COVID-19, a disease caused by SARS-CoV-2. Although SARS-CoV-2 is well known to promote a prothrombotic state, less is known about the thrombosis risk in PASC. Our objective was to evaluate platelet function and thrombotic potential in patients following recovery from SARS-CoV-2, but with clear symptoms of patients with PASC. METHODS: patients with PASC and matched healthy controls were enrolled in the study on average 15 months after documented SARS-CoV-2 infection. Platelet activation was evaluated by light transmission aggregometry (LTA) and flow cytometry in response to platelet surface receptor agonists. Thrombosis in platelet-deplete plasma was evaluated by Factor Xa activity. A microfluidics system assessed thrombosis in whole blood under shear stress conditions. RESULTS: A mild increase in platelet aggregation in patients with PASC through the thromboxane receptor was observed, and platelet activation through the glycoprotein VI (GPVI) receptor was decreased in patients with PASC compared to age- and sex-matched healthy controls. Thrombosis under shear conditions as well as Factor Xa activity were reduced in patients with PASC. Plasma from patients with PASC was an extremely potent activator of washed, healthy platelets - a phenomenon not observed when stimulating healthy platelets after incubation with plasma from healthy individuals. CONCLUSIONS: patients with PASC show dysregulated responses in platelets and coagulation in plasma, likely caused by a circulating molecule that promotes thrombosis. A hitherto undescribed protective response appears to exist in patients with PASC to counterbalance ongoing thrombosis that is common to SARS-CoV-2 infection.

Comparison of Clinical Outcomes in Patients with Active Cancer Receiving Rivaroxaban or Low-Molecular-Weight Heparin: The OSCAR-UK Study.

BACKGROUND: In most patients with cancer-associated venous thromboembolism (CT), essentially those not at high risk of bleeding, guidelines recommend treatment with direct oral anticoagulants as an alternative to low-molecular-weight heparins (LMWHs). Population-based studies comparing these therapies are scarce. OBJECTIVES: To compare the risk of venous thromboembolism (VTE) recurrences, significant bleeding, and all-cause mortality in patients with CT receiving rivaroxaban or LMWHs. PATIENTS/METHODS: Using UK Clinical Practice Research Datalink data from 2013 to 2020, we generated a cohort of patients with first CT treated initially with either rivaroxaban or LMWH. Patients were observed 12 months for VTE recurrences, significant bleeds (major bleeds or clinically relevant nonmajor bleeding requiring hospitalization), and all-cause mortality. Overlap weighted sub-distribution hazard ratios (SHRs) compared rivaroxaban with LMWH in an intention-to-treat analysis. RESULTS: The cohort consisted of 2,259 patients with first CT, 314 receiving rivaroxaban, and 1,945 LMWH, mean age 72.4 and 66.9 years, respectively. In the 12-month observational period, 184 person-years following rivaroxaban and 1,057 following LMWH, 10 and 66 incident recurrent VTE events, 20 and 102 significant bleeds, and 10 and 133 deaths were observed in rivaroxaban and LMWH users, respectively. The weighted SHR at 12 months for VTE recurrences in rivaroxaban compared with LMWH were 0.80 (0.37-1.73); for significant bleeds 1.01 (0.57-1.81); and for all-cause mortality 0.49 (0.23-1.06). CONCLUSION: Patients with CT, not at high risk of bleeding, treated with either rivaroxaban or LMWH have comparable effectiveness and safety outcomes. This supports the recommendation that rivaroxaban is a reasonable alternative to LMWH for the treatment of CT.

Management of venous thromboembolism in patients with active cancer.

Venous thromboembolism (VTE) is a major health burden in patients with cancer, causing morbidity, emergency room visits, hospitalizations, and death. Treatment is challenging, as it is necessary to balance the risk of recurrent thrombosis and bleeding associated with anticoagulants. Treatment paradigms are shifting from low-molecular-weight heparin monotherapy. Multiple recent randomized controlled trials have demonstrated the safety and efficacy of direct oral anticoagulants in this setting. Current studies are evaluating factor XI inhibitors as potential treatments for cancer-associated VTE.

Distinct intratumoral microbiome of young-onset and average-onset colorectal cancer.

BACKGROUND: The unexplained rise of young-onset CRC (yoCRC, age <50 years) is of concern. Evidence suggests that microbial dysbiosis may be a contributing factor, but the tumor microbial profile of yoCRC in comparison to average-onset CRC (aoCRC, age >60) has not been fully investigated. METHODS: 16S rRNA amplicon sequencing was performed in tumor and paired adjacent non-malignant fresh frozen tissue specimens prospectively collected from 136 yoCRC and 140 aoCRC patients. Phyloseq, microbiomeSeq, metagenomeSeq, and NetComi were utilized for bioinformatics analysis. Statistical tests included Fisher's exact test, ANOVA, PERMANOVA with Bonferroni correction, linear regression, and Wilcoxon test. p-value <0.05 was considered statistically significant. FINDINGS: yoCRC patients were more likely to have left-sided (72.8 vs. 54.3%), rectal (36.7% vs. 25%), and stage IV (28% vs. 15%) tumors. yoCRC tumors had significantly higher microbial alpha diversity (p = 1.5 × 10-5) and varied beta diversity (R2 = 0.31, p = 0.013) than aoCRC tumors. yoCRC tumors were enriched with Akkermansia and Bacteroides, whereas aoCRC tumors showed greater relative abundances of Bacillus, Staphylococcus, Listeria, Enterococcus, Pseudomonas, Fusobacterium, and Escherichia/Shigella. Akkermansia had a predominantly negative correlation with the microbial communities in yoCRC tumors. yoCRC and aoCRC tumors had distinct microbial profiles associated with tumor location, sidedness, stage, and obesity. Fusobacterium (R2 = -0.23, p = 0.001) and Akkermansia (R2 = 0.05, p = 0.001) abundance correlated with overall survival in yoCRC. INTERPRETATION: Our study provides a comprehensive understanding of the microbial perturbations in yoCRC tumors. We identify microbial candidates that may highlight a distinct pathogenesis of yoCRC and serve as preventive, diagnostic, and therapeutic targets. FUNDING: Sondra and Stephen Hardis Chair in Oncology Research (A.A.K.).

Neutrophil extracellular traps induced by chemotherapy inhibit tumor growth in murine models of colorectal cancer.

Neutrophil extracellular traps (NETs), a web-like structure of cytosolic and granule proteins assembled on decondensed chromatin, kill pathogens and cause tissue damage in diseases. Whether NETs can kill cancer cells is unexplored. Here, we report that a combination of glutaminase inhibitor CB-839 and 5-FU inhibited the growth of PIK3CA-mutant colorectal cancers (CRCs) in xenograft, syngeneic, and genetically engineered mouse models in part through NETs. Disruption of NETs by either DNase I treatment or depletion of neutrophils in CRCs attenuated the efficacy of the drug combination. Moreover, NETs were present in tumor biopsies from patients treated with the drug combination in a phase II clinical trial. Increased NET levels in tumors were associated with longer progression-free survival. Mechanistically, the drug combination induced the expression of IL-8 preferentially in PIK3CA-mutant CRCs to attract neutrophils into the tumors. Further, the drug combination increased the levels of ROS in neutrophils, thereby inducing NETs. Cathepsin G (CTSG), a serine protease localized in NETs, entered CRC cells through the RAGE cell surface protein. The internalized CTSG cleaved 14-3-3 proteins, released BAX, and triggered apoptosis in CRC cells. Thus, our studies illuminate a previously unrecognized mechanism by which chemotherapy-induced NETs kill cancer cells.

Risk of Thromboembolism in Patients Receiving Immunotherapy-Based Combinations as Front-Line Therapy for Metastatic Renal Cell Carcinoma.

BACKGROUND: Most patients with treatment-naïve metastatic renal cell carcinoma (mRCC) receive combination-based immunotherapy with either 2 immune-oncology checkpoint inhibitors (IO/IO) or an IO agent in combination with a vascular endothelial growth factor receptor (VEGF-R) tyrosine kinase inhibitor (IO/TKI). The rates of thromboembolism (TE) in these cohorts are not clearly described and can potentially impact decision-making between IO/IO and IO/TKI. METHODS: We conducted a retrospective investigation of patients with treatment-naïve mRCC treated with IO-based combinations between January 2015 and April 2021 at the Cleveland Clinic. TE events, including venous and arterial, were identified in each group. Competing risk regression was done to identify factors associated with the development of TE following therapy, with all-cause mortality treated as a competing event. RESULTS: Of 180 patients identified, 77 (43%) received IO/TKI and 103 (57%) received IO/IO. Median age was 65 years, 75% were male, and 80% had clear cell histology. Baseline characteristics were similar between the 2 groups. At a median follow-up of 22.0 months, 10.0% of all patients had a TE. The one-year incidence of TE was 8.1% (95% CI: 3.3%-15.8%) with IO/TKI and 9.8% (95% CI: 5.0%-16.5%) with IO/IO and was not significantly different between the 2 groups (HR 0.89, 95% CI: 0.35%-2.28%). Occurrence of TE was associated with decreased overall survival regardless of IO/IO or IO/TKI therapy (HR 2.80, 95% CI: 1.57-5.02). There was no difference in incidence of TE based on patient age, gender, prior history of TE, International Metastatic Renal Cell Carcinoma (IMDC) risk group, or Khorana score. CONCLUSIONS: Incidence of TE is similar between IO/IO and IO/TKI regimens in treatment-naïve mRCC and is also associated with decreased overall survival. While risk of TE may not guide decision-making in choice of front-line mRCC therapy, careful attention should be given to the high risk of TE in this population.

Dysregulated Platelet Function in Patients with Post-Acute Sequelae of COVID-19.

Background: Post-acute sequelae of COVID-19 (PASC), also referred as Long-COVID, sometimes follows COVID-19, a disease caused by SARS-CoV-2. While SARS-CoV-2 is well-known to promote a prothrombotic state, less is known about the thrombosis risk in PASC. Aim: Our objective was to evaluate the platelet function and thrombotic potential in patients following recovery from SARS-CoV-2 with clear symptoms of PASC. Methods: PASC patients and matched healthy controls were enrolled in the study on average 15 months after documented SARS-CoV-2 infection. Platelet activation was evaluated by Light Transmission Aggregometry (LTA) and flow cytometry in response to platelet surface receptor agonists. Thrombosis in platelet-deplete plasma was evaluated by Factor Xa activity. A microfluidics system assessed thrombosis in whole blood under shear stress conditions. Results: A mild increase in platelet aggregation in PASC patients through the thromboxane receptor was observed and platelet activation through the glycoprotein VI (GPVI) receptor was decreased in PASC patients compared to age- and sex-matched healthy controls. Thrombosis under shear conditions as well as Factor Xa activity were reduced in PASC patients. Plasma from PASC patients was an extremely potent activator of washed, healthy platelets - a phenomenon not observed when stimulating healthy platelets after incubation with plasma from healthy individuals. Conclusions: PASC patients show dysregulated responses in platelets and coagulation in plasma, likely caused by a circulating molecule that promotes thrombosis. A hitherto undescribed protective response appears to exists in PASC patients to counterbalance ongoing thrombosis that is common to SARS-CoV-2 infection.

Genomic Predictors Associated With Exceptional Response to Systemic Therapy in Advanced Pancreatic Cancer.

INTRODUCTION: Exceptional response to therapy is rare in patients with advanced pancreatic cancer. This study explored potential genomic differences between typical and exceptional responses that could confer more favorable biology. METHODS: We included exceptional responders and controls with advanced pancreatic cancer from Cleveland Clinic from April 2013 to August 2017. Exceptional responders were defined as patients with an overall survival of more than 18 months for metastatic disease and more than 24 months for locally advanced disease. Clinical data were obtained, and next-generation sequencing was performed. Statistical analyses comparing the 2 groups were performed using descriptive statistics, the Kaplan-Meier method, and the log-rank test. RESULTS: The study comprised 4 exceptional responders and 6 controls. Both groups were well balanced in age, sex, race, and treatment regimens. Exceptional responders had significantly fewer nonsynonymous mutations than controls (2.25 vs 5.17; P = .014). A mutation count of less than 3 was associated with significantly better progression-free survival (17.2 vs 2.3 months; P = .002) and overall survival (29.4 vs 4.6 months; P = .013). Tumor mutational burden did not differ between exceptional responders and controls (4.88 vs 5.70 mut/Mb; P = .39). CONCLUSION: A lower number of nonsynonymous mutations may correlate with exceptional outcomes in patients with pancreatic cancer. These findings should encourage future studies into genomic signatures of exceptional response.

Referral, Uptake, and Outcome of Genetic Counseling and Testing in Patients With Early-Onset Colorectal Cancer.

BACKGROUND: The incidence of early-onset colorectal cancer (EOCRC) is rapidly increasing. Pathogenic germline variants (PGVs) are detected in 16% to 20% of patients who have EOCRC, highlighting a need for genetic counseling (GC) and multigene panel testing in these patients. We aimed to determine the rate of referral to GC and uptake and outcomes of germline testing in patients with EOCRC. METHODS: We conducted a retrospective cohort study of patients aged <50 years diagnosed with colorectal cancer (CRC) from 2010 to 2019 at Cleveland Clinic. Demographic data were extracted, including age, sex, self-reported race, and family history of CRC. The proportions of patients with GC referral and completion of GC and genetic testing were investigated, and genetic testing results were analyzed. Multivariable logistic regression analysis was conducted to identify factors independently associated with GC referral and uptake. RESULTS: A total of 791 patients with EOCRC (57% male and 43% female) were included; 62% were referred for GC, and of those who were referred, 79% completed a GC appointment and 77% underwent genetic testing. Of those who underwent testing, 21% had a PGV detected; 82% were in known CRC-associated genes, with those associated with Lynch syndrome and familial adenomatous polyposis the most common, and 11% were in other actionable genes. Referral to GC was positively associated with family history of CRC (odds ratio [OR], 2.11; 95% CI, 1.51-2.96) and more recent year of diagnosis (2010-2013 vs 2017-2019; OR, 5.36; 95% CI, 3.59-8.01) but negatively associated with older age at diagnosis (OR, 0.89; 95% CI, 0.86-0.92). CONCLUSIONS: Referral to GC for patients with EOCRC is increasing over time; however, even in recent years, almost 25% of patients were not referred for GC. We found that 1 in 5 patients with EOCRC carry actionable PGVs, highlighting the need for health systems to implement care pathways to optimize GC referral and testing in all patients with EOCRC.

Cancer and the Risk of Perioperative Arterial Ischemic Events.

BACKGROUND AND AIMS: Most cancer patients require surgery for diagnosis and treatment. This study evaluated whether cancer is a risk factor for perioperative arterial ischemic events. METHODS: The primary cohort included patients registered in the National Surgical Quality Improvement Program (NSQIP) between 2006-2016. The secondary cohort included Healthcare Cost and Utilization Project (HCUP) claims data from 11 U.S. states between 2016-2018. Study populations comprised patients who underwent inpatient (NSQIP, HCUP) or outpatient (NSQIP) surgery. Study exposures were disseminated cancer (NSQIP) and all cancers (HCUP). The primary outcome was a perioperative arterial ischemic event, defined as myocardial infarction or stroke diagnosed within 30 days after surgery. RESULTS: Among 5,609,675 NSQIP surgeries, 2.2% involved patients with disseminated cancer. The perioperative arterial ischemic event rate was 0.96% among patients with disseminated cancer versus 0.48% among patients without (HR, 2.01; 95% CI, 1.90-2.13). In Cox analyses adjusting for demographics, functional status, comorbidities, surgical specialty, anesthesia type, and clinical factors, disseminated cancer remained associated with higher risk of perioperative arterial ischemic events (HR, 1.37; 95% CI, 1.28-1.46). Among 1,341,658 surgical patients in the HCUP cohort, 11.8% had a diagnosis of cancer. A perioperative arterial ischemic event was diagnosed in 0.74% of patients with cancer versus 0.54% of patients without cancer (HR, 1.35; 95% CI, 1.27-1.43). In Cox analyses adjusted for demographics, insurance, comorbidities, and surgery type, cancer remained associated with higher risk of perioperative arterial ischemic events (HR, 1.31; 95% CI, 1.21-1.42). CONCLUSIONS: Cancer is an independent risk factor for perioperative arterial ischemic events.

Rivaroxaban Versus Low-Molecular-Weight Heparins in a Broad Cohort of Patients With Cancer-Associated Venous Thromboembolism: An Analysis of the OSCAR-US Program.

Cancer-associated venous thromboembolism (CAT) guidelines recommend direct oral anticoagulants as alternatives to low-molecular-weight heparin (LMWH) in most patients. This study compared the effectiveness and safety of rivaroxaban versus LMWH for a broad CAT cohort. The cohort study used electronic health data from January 2012 to December 2020 to evaluate patients with active cancer experiencing acute venous thromboembolism (VTE) and treated with rivaroxaban or LMWH. Propensity score-overlap weighted hazard ratios (HRs) and 95% confidence intervals (CIs) for VTE, bleeding-related hospitalization, and all-cause mortality were calculated. In total, 4935 patients were identified (27.9% on rivaroxaban and 72.1% on LMWH). The cancer types included gastrointestinal (29.4%), genitourinary (26.2%), lung (24.0%), breast (19.7%), and hematologic (14.4%). Rivaroxaban was associated with a reduction in recurrent VTE versus LMWH among all patients with cancer (HR = 0.78; 95%CI = 0.61-0.99) at 3 months. No differences in bleeding-related hospitalization or all-cause mortality were observed. Directionally similar results to those at 3 months were observed at 6 months for all outcomes. In conclusion, we observed fewer recurrent VTE cases and no increase in bleeding-related hospitalizations with rivaroxaban versus LMWH at 3 months in this patient cohort with various cancer types.

Rivaroxaban versus Apixaban for Treatment of Cancer-Associated Venous Thromboembolism in Patients at Lower Risk of Bleeding.

This retrospective study, utilizing U.S. electronic health record (EHR) data from January 2013 to December 2020, sought to assess whether rivaroxaban and apixaban had similar effectiveness and safety in the treatment of cancer-associated venous thromboembolism (VTE) in patients with a cancer type not associated with a high risk of bleeding. We included adults diagnosed with active cancer, excluding esophageal, gastric, unresected colorectal, bladder, noncerebral central nervous system cancers and leukemia, who experienced VTE and received a therapeutic VTE dose of rivaroxaban or apixaban on day 7 post-VTE, and were active in the EHR ≥12 months prior to the VTE. Primary outcome was the composite of recurrent VTE or any bleed resulting in hospitalization at 3 months. Secondary outcomes included recurrent VTE, any bleed resulting in hospitalization, any critical organ bleed, and composites of these outcomes at 3 and 6 months. Inverse probability of treatment-weighted Cox regression was used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). We included 1,344 apixaban and 1,093 rivaroxaban patients. At 3 months, rivaroxaban was found to have similar hazard to apixaban for developing recurrent VTE or any bleed resulting in hospitalization (HR: 0.87; 95% CI: 0.60-1.27). No differences were observed between cohorts for this outcome at 6 months (HR: 1.00; 95% CI: 0.71-1.40) or for any other outcome at 3 or 6 months. In conclusion, patients receiving rivaroxaban or apixaban showed similar risks of the composite of recurrent VTE or any bleed resulting in hospitalization in patients with cancer-associated VTE. This study was registered at www.clinicaltrials.gov as #NCT05461807. Key Points Rivaroxaban and apixaban have similar effectiveness and safety for treatment of cancer-associated VTE through 6 months.Clinicians should therefore consider patient preference and adherence when choosing the optimal anticoagulant.

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.

Effectiveness and Safety of Rivaroxaban and Low Molecular Weight Heparin in Cancer-Associated Venous Thromboembolism.

Background: Direct-acting oral anticoagulants (DOACs) are alternatives to low molecular weight heparin (LMWH) in most cancer-associated thrombosis (CAT) patients. Objectives: This study sought to compare the effectiveness and safety of rivaroxaban and LMWH for venous thromboembolism (VTE) treatment in patients with an active cancer type not associated with a high risk of DOAC bleeding. Methods: An analysis of electronic health records from January 2012 to December 2020 was performed. Patients were adults, had active cancer, experienced an index CAT event, and were treated with rivaroxaban or LMWH. Patients with cancers with an established high risk of bleeding on DOACs were excluded. Baseline covariates were balanced using propensity score-overlap weighting. HRs with 95% CIs were calculated. Results: We identified 3,708 CAT patients treated with rivaroxaban (29.5%) or LMWH (70.5%). The median (25th-75th percentiles) time on anticoagulation was 180 (69-365) and 96 (40-336) days for rivaroxaban and LMWH patients. At 3 months, rivaroxaban was associated with a 31% reduced risk of recurrent VTE vs LMWH (4.2% vs 6.1%; HR: 0.69; 95% CI: 0.51-0.92). No difference in bleeding-related hospitalizations or all-cause mortality was observed (HR: 0.79; 95% CI: 0.55-1.13 and HR: 1.07; 95% CI: 0.85-1.35, respectively). Rivaroxaban reduced the recurrent VTE risk (HR: 0.74; 95% CI: 0.57-0.97) but not bleeding-related hospitalizations or all-cause mortality at 6 months. At 12 months, no difference was observed between cohorts for any of the previously mentioned outcomes. Conclusions: Among active cancer patients experiencing VTE and not at high risk of bleeding on DOACs, rivaroxaban was associated with a reduced risk of recurrent VTE versus LMWHs at 3 and 6 months but not 12 months. (Observational Study in Cancer-Associated Thrombosis for Rivaroxaban-United States Cohort [OSCAR-US]; NCT04979780).