Treatment and Long-Term Clinical Outcomes of Incidental Pulmonary Embolism in Patients With Cancer: An International Prospective Cohort Study

Venous thromboembolism in cancer patients: a population-based cohort study

The incidence of venous thromboembolism (VTE) in cancer patients may have changed in the past decade, possibly due to novel cancer therapies, improved survival, and high-resolution imaging. Danish medical registries were used to identify 499 092 patients with a first-time cancer diagnosis between 1997 and 2017, who were matched to 1 497 276 comparison individuals without cancer from the general population. We computed cumulative incidences of VTE 6 and 12 months after the diagnosis/index date. Hazard ratios (HRs) were calculated using Cox regression. Risk factors were examined by computing subdistribution hazard ratios (SHRs) in a competing-risk analysis. Cumulative incidence of VTE 12 months after the cancer diagnosis/index date was 2.3% (95% confidence interval [CI], 2.2% to 2.3%) in the cancer cohort and 0.35% (95% CI, 0.34% to 0.36%) in the comparison cohort (HR, 8.5; 95% CI, 8.2-8.8). Important risk factors for cancer patients were prior VTE (SHR, 7.6; 95% CI, 7.2-8.0), distant metastasis (SHR, 3.2; 95% CI, 2.9-3.4), and use of chemotherapy (SHR, 3.4; 95% CI, 3.1-3.7), protein kinase inhibitors (SHR, 4.1; 95% CI, 3.4-4.9), antiangiogenic therapy (SHR, 4.4; 95% CI, 3.8-5.2), and immunotherapy (SHR, 3.6; 2.8-4.6). Twelve-month incidence in the cancer cohort increased from 1.0% (95% CI, 0.9% to 1.2%) in 1997 to 3.4% (95% CI, 2.9% to 4.0%) in 2017, which was paralleled by improved 12-month survival and increased use of computed tomography scans, chemotherapy, and targeted therapies. In conclusion, the risk of VTE in cancer patients is increasing steadily and is ninefold higher than in the general population.

Treatment of venous thromboembolism in cancer patients: The dark side of the moon

Venous thromboembolism (VTE) is a common complication in patients with cancer. The risk of emergent VTE is four- to seven-fold higher in cancer patients compared to non-cancer patients. Although the therapeutic armamentarium for cancer-associated VTE has been recently implemented, anticoagulant treatment remains challenging because of the increased risk of recurrent VTE and bleeding. Several international societies and expert panels released clinical practice guidelines on VTE treatment which are mostly focused on the general cancer population. Nevertheless, recommendations for the management of VTE in patients with peculiar clinical presentations are inconsistent and remain elusive due to the lack of pertinent evidence. The challenging clinical scenarios include, among others, patients with thrombocytopenia, renal impairment, gastrointestinal cancer, primary or metastatic brain cancer, distal thrombosis of the lower extremities, catheter-related VTE, splanchnic thrombosis, incidental VTE, extreme body weight, recurrent VTE during treatment, as well as the optimal duration of anticoagulant treatment in patients with active disease who have received 3 to 6 months of anticoagulation. Herein, we present a critical overview on VTE management in these challenging clinical settings, discuss potential approaches, and include some calls to action for future clinical research.

American Society of Hematology 2021 guidelines for management of venous thromboembolism: prevention and treatment in patients with cancer

BACKGROUND

Venous thromboembolism (VTE) is a common complication among patients with cancer. Patients with cancer and VTE are at a markedly increased risk for morbidity and mortality.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in their decisions about the prevention and treatment of VTE in patients with cancer.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The guideline development process was supported by updated or new systematic evidence reviews. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess evidence and make recommendations.

RESULTS

Recommendations address mechanical and pharmacological prophylaxis in hospitalized medical patients with cancer, those undergoing a surgical procedure, and ambulatory patients receiving cancer chemotherapy. The recommendations also address the use of anticoagulation for the initial, short-term, and long-term treatment of VTE in patients with cancer.

CONCLUSIONS

Strong recommendations include not using thromboprophylaxis in ambulatory patients receiving cancer chemotherapy at low risk of VTE and to use low-molecular-weight heparin (LMWH) for initial treatment of VTE in patients with cancer. Conditional recommendations include using thromboprophylaxis in hospitalized medical patients with cancer, LMWH or fondaparinux for surgical patients with cancer, LMWH or direct oral anticoagulants (DOAC) in ambulatory patients with cancer receiving systemic therapy at high risk of VTE and LMWH or DOAC for initial treatment of VTE, DOAC for the short-term treatment of VTE, and LMWH or DOAC for the long-term treatment of VTE in patients with cancer.

Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy

BACKGROUND

Venous thromboembolism (VTE) often complicates the clinical course of cancer. The risk is further increased by chemotherapy, but the trade-off between safety and efficacy of primary thromboprophylaxis in cancer patients treated with chemotherapy is uncertain. This is the third update of a review first published in February 2012.

OBJECTIVES

To assess the efficacy and safety of primary thromboprophylaxis for VTE in ambulatory cancer patients receiving chemotherapy compared with placebo or no thromboprophylaxis, or an active control intervention.

SEARCH METHODS

For this update, the Cochrane Vascular Information Specialist searched the Cochrane Vascular, CENTRAL, MEDLINE, Embase and CINAHL databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 3 August 2020. We also searched the reference lists of identified studies and contacted content experts and trialists for relevant references.

SELECTION CRITERIA

Randomised controlled trials comparing any oral or parenteral anticoagulant or mechanical intervention to no thromboprophylaxis or placebo, or comparing two different anticoagulants.

DATA COLLECTION AND ANALYSIS

We extracted data on risk of bias, participant characteristics, interventions, and outcomes including symptomatic VTE and major bleeding as the primary effectiveness and safety outcomes, respectively. We applied GRADE to assess the certainty of evidence.

MAIN RESULTS

We identified six additional randomised controlled trials (3326 participants) for this update, bringing the included study total to 32 (15,678 participants), all evaluating pharmacological interventions and performed mainly in people with locally advanced or metastatic cancer. The certainty of the evidence ranged from high to very low across the different outcomes and comparisons. The main limiting factors were imprecision and risk of bias. Thromboprophylaxis with direct oral anticoagulants (direct factor Xa inhibitors apixaban and rivaroxaban) may decrease the incidence of symptomatic VTE (risk ratio (RR) 0.43, 95% confidence interval (CI) 0.18 to 1.06; 3 studies, 1526 participants; low-certainty evidence); and probably increases the risk of major bleeding compared with placebo (RR 1.74, 95% CI 0.82 to 3.68; 3 studies, 1494 participants; moderate-certainty evidence). When compared with no thromboprophylaxis, low-molecular-weight heparin (LMWH) reduced the incidence of symptomatic VTE (RR 0.62, 95% CI 0.46 to 0.83; 11 studies, 3931 participants; high-certainty evidence); and probably increased the risk of major bleeding events (RR 1.63, 95% CI 1.12 to 2.35; 15 studies, 7282 participants; moderate-certainty evidence). In participants with multiple myeloma, LMWH resulted in lower symptomatic VTE compared with the vitamin K antagonist warfarin (RR 0.33, 95% CI 0.14 to 0.83; 1 study, 439 participants; high-certainty evidence), while LMWH probably lowers symptomatic VTE more than aspirin (RR 0.51, 95% CI 0.22 to 1.17; 2 studies, 781 participants; moderate-certainty evidence). Major bleeding was observed in none of the participants with multiple myeloma treated with LMWH or warfarin and in less than 1% of those treated with aspirin. Only one study evaluated unfractionated heparin against no thromboprophylaxis, but did not report on VTE or major bleeding. When compared with placebo or no thromboprophylaxis, warfarin may importantly reduce symptomatic VTE (RR 0.15, 95% CI 0.02 to 1.20; 1 study, 311 participants; low-certainty evidence) and may result in a large increase in major bleeding (RR 3.82, 95% CI 0.97 to 15.04; 4 studies, 994 participants; low-certainty evidence). One study evaluated antithrombin versus no antithrombin in children. This study did not report on symptomatic VTE but did report any VTE (symptomatic and incidental VTE). The effect of antithrombin on any VTE and major bleeding is uncertain (any VTE: RR 0.84, 95% CI 0.41 to 1.73; major bleeding: RR 0.78, 95% CI 0.03 to 18.57; 1 study, 85 participants; very low-certainty evidence).

AUTHORS' CONCLUSIONS

In ambulatory cancer patients, primary thromboprophylaxis with direct factor Xa inhibitors may reduce the incidence of symptomatic VTE (low-certainty evidence) and probably increases the risk of major bleeding (moderate-certainty evidence) when compared with placebo. LMWH decreases the incidence of symptomatic VTE (high-certainty evidence), but increases the risk of major bleeding (moderate-certainty evidence) when compared with placebo or no thromboprophylaxis. Evidence for the use of thromboprophylaxis with anticoagulants other than direct factor Xa inhibitors and LMWH is limited. More studies are warranted to evaluate the efficacy and safety of primary prophylaxis in specific types of chemotherapeutic agents and types of cancer, such as gastrointestinal or genitourinary cancer.

Clinical characteristics and 3-month outcomes in cancer patients with incidental versus clinically suspected and confirmed pulmonary embolism

Background

Current guidelines suggest treating cancer patients with incidental pulmonary embolism (PE) similarly to those with clinically suspected and confirmed PE. However, the natural history of these presentations has not been thoroughly compared.

Methods

We used the data from the RIETE (Registro Informatizado de Enfermedad TromboEmbólica) registry to compare the 3-month outcomes in patients with active cancer and incidental PE versus those with clinically suspected and confirmed PE. The primary outcome was 90-day all-cause mortality. Secondary outcomes were PE-related mortality, symptomatic PE recurrences and major bleeding.

Results

From July 2012 to January 2019, 946 cancer patients with incidental asymptomatic PE and 2274 with clinically suspected and confirmed PE were enrolled. Most patients (95% versus 90%) received low-molecular-weight heparin therapy. During the first 90 days, 598 patients died, including 42 from PE. Patients with incidental PE had a lower all-cause mortality rate than those with suspected and confirmed PE (11% versus 22%; OR 0.43, 95% CI 0.34–0.54). Results were consistent for PE-related mortality (0.3% versus 1.7%; OR 0.18, 95% CI 0.06–0.59). Multivariable analysis confirmed that patients with incidental PE were at lower risk of death (adjusted OR 0.43, 95% CI 0.34–0.56). Overall, 29 (0.9%) patients developed symptomatic PE recurrences, and 122 (3.8%) had major bleeding. There were no significant differences in PE recurrences (OR 0.62, 95% CI 0.25–1.54) or major bleeding (OR 0.78, 95% CI 0.51–1.18).

Conclusions

Cancer patients with incidental PE had a lower mortality rate than those with clinically suspected and confirmed PE. Further studies are required to validate these findings, and to explore optimal management strategies in these patients.

Incidence of venous thromboembolic events in cancer patients receiving immunotherapy: a single-institution experience

BACKGROUND

Cancer and cancer therapies have been associated with an increased incidence of venous thromboembolic events (VTE). However, the incidence of VTE in patients on immunotherapy has not been well characterized. The aim of this study was to assess the incidence of VTE in cancer patients receiving immunotherapy and ascertain its prognostic utility.

MATERIALS AND METHODS

We conducted a single-institution retrospective study, including all cancer patients treated with anti-Programmed cell Death 1 (PD-1), anti-Programmed cell Death Ligand-1 (PD-L1), anti-Cytotoxic T-Lymphocyte-Associated Protein 4 (CTLA4), a combination of anti-PD-1/anti-PD-L1 and anti-CTLA4 or a combination including any of these drugs with chemotherapy, antiangiogenic agents or both between June 2013 and April 2019 at La Paz University Hospital, Madrid (Spain).

RESULTS

We selected 229 patients. VTE occurred in 16 of 229 patients (7%). VTE occurred more frequently in patients with lung cancer followed by melanoma. Female sex and melanoma were independently associated with an increased risk of VTE. 12 of 16 VTE (75%) were symptomatic. Progressive disease to immunotherapy [HR 31.60 (95% CI 11.44-87.22), p = 0.00], lung cancer [HR 2.55 (95% CI 1.34-4.86), p = 0.00] and melanoma [HR 2.42 (1.20-4.86), p = 0.01] were independently associated with shorter OS. VTE occurrence was not independently associated with shorter OS [HR 1.33 (95% CI 0.63-2.80), p = 0.44].

CONCLUSIONS

The incidence of VTE in cancer patients receiving immunotherapy in our study appeared to be similar to the incidence previously reported in other series of cancer patients treated with systemic therapies. VTE occurrence did not correlate with the prognosis. Further and prospective studies are needed to derive definitive conclusions.

Clinical Outcomes of Incidental Venous Thromboembolism in Cancer and Noncancer Patients: The SWIss Venous ThromboEmbolism Registry (SWIVTER)

OBJECTIVE

 In patients with cancer-associated venous thromboembolism (VTE), the risk of recurrence is similar after incidental and symptomatic events. It is unknown whether the same applies to incidental VTE not associated with cancer.

METHODS AND RESULTS

 We compared baseline characteristics, anticoagulation therapy, all-cause mortality, and VTE recurrence rates at 90 days between patients with incidental (n = 131; 52% without cancer) and symptomatic (n = 1,931) VTE included in the SWIss Venous ThromboEmbolism Registry (SWIVTER). After incidental VTE, 114 (87%) patients received anticoagulation therapy for at least 3 months. The mortality rate was 9.2% after incidental and 8.4% after symptomatic VTE for hazard ratio (HR) 1.10 (95% confidence interval [CI] 0.49-2.50). After adjustment for competing risk of death, recurrence rate was 3.1 versus 2.8%, respectively, for sub-HR 1.07 (95% CI 0.39-2.93). These results were consistent among cancer (mortality: 15.9% vs. 12.6%; HR 1.32, 95% CI 0.67-2.59; recurrence: 4.8% vs. 4.7%; HR 1.02, 95% CI 0.30-3.42) and noncancer patients (mortality: 2.9% vs. 2.1%; HR 1.37, 95% CI 0.33-5.73; recurrence: 1.5% vs. 2.3%; HR 0.63, 95% CI 0.09-4.58). Patients with incidental VTE who received anticoagulation therapy for at least 3 months had lower mortality (4% vs. 41%) and recurrence rate (1% vs. 18%) compared with those who did not.

CONCLUSION

 In SWIVTER, more than half of incidental VTE events occurred in noncancer patients who often received anticoagulation therapy. Among noncancer patients, early mortality and recurrence rates were similar after incidental versus symptomatic VTE. Our findings suggest that anticoagulation therapy for incidental VTE may be beneficial regardless of the presence of cancer.

Challenging anticoagulation cases: A case of incidental subsegmental pulmonary embolism in a patient with cancer

Cancer therapy and progress in quality of imaging technologies for cancer surveillance and staging are in cause for the increase incidence of smaller incidental pulmonary embolism (PE). The clinical significance of incidental subsegmental pulmonary embolism (SSPE) is hard to define, balancing between possible false positive result, hypercoagulability signal, and truly venous thromboembolism (VTE) event. Evidence for optimal management of such findings are largely extrapolated from symptomatic SSPE in non-cancer patients and from symptomatic, more proximal PE in cancer patients. Current practice guidelines vary but some suggest withholding anticoagulation in selected patients. However, most SSPEs, incidental or not, should be treated as any other cancer-associated PE due to likely similar prognosis. Choice and duration of anticoagulation are extended from existing knowledge on more proximal PE.

Efficacy and safety of direct oral anticoagulants for secondary prevention of cancer associated thrombosis: a meta-analysis of randomized controlled trials

Direct oral anticoagulants (DOACs) may be good alternatives to low molecular weight heparin (LMWH) or vitamin K antagonists (VKA) for treatment of cancer associated thrombosis (CAT). We conducted a meta-analysis of ten randomized clinical trials to evaluate the efficacy and safety of DOACs in patients with CAT. All had study populations composed in entirety or in part of patients with CAT. The primary outcome (efficacy) was recurrent VTE and the secondary outcomes (safety outcomes) included major bleeding, clinically relevant non-major bleeding (CRNMB), and all bleeding (major bleeding + CRNMB). Participants treated with DOACs had lower risk of recurrent VTE, overall (RR 0.63; 95% CI 0.51-0.79; p < 0.0001), compared to LMWH (RR 0.57; 95% CI 0.40-0.83; p = 0.003), but not compared to VKA (RR 0.69; 95% CI 0.44-1.06; p = 0.09). Compared to LMWH, DOACs showed no difference in major bleeding risk (RR 1.31; 95% CI 0.78-2.18; p = 0.31), though had higher risk of CRNMB (RR 1.60; 95% CI 1.13-2.26; p = 0.008) and all bleeding (RR 1.49; 95% CI 1.10-2.01; p = 0.010). These results indicate that DOACs are more effective than LMWH for prevention of recurrent VTE with CAT though carry an increased risk for non-major bleeding compared to standard of care, LMWH.

Prevention and treatment of cancer-associated thrombosis

Cancer is a hypercoagulable state with an associated increased risk of venous thromboembolism (vte) that is further amplified in individuals who undergo chemotherapy. Compared with patients having cancer alone or vte alone, patients who develop cancer-associated vte have a significantly poorer prognosis. The risks of recurrent vte despite appropriate anticoagulation therapy and of bleeding are also higher in patients with cancer than in those without. For those reasons, the prevention and appropriate management of cancer-associated thrombosis is of paramount importance. Although low-molecular-weight heparin has been the standard of care for the prevention and treatment of cancer-associated thrombosis, direct oral anticoagulants are increasingly being adopted as an effective and safe alternative.

Managing the competing risks of thrombosis, bleeding, and anticoagulation in patients with malignancy

The association between malignancy and thrombosis has been recognized for over a century and a half. Patients with cancer have an elevated risk of both initial and recurrent venous thromboembolism (VTE) compared with patients without cancer owing to cancer- and patient-specific factors. Recurrent VTE is common despite anticoagulation, presenting additional management challenges. Patients with cancer also have an increased risk of bleeding when on anticoagulants compared with patients without cancer. This bleeding risk is heightened by the thrombocytopenia common in patients with hematologic malignancies and those treated with intensive myelosuppressive chemotherapy regimens. Despite the advancements in cancer-directed therapy made over the past 15 years, numerous large studies have confirmed that bleeding and VTE recurrence rates remain high in cancer patients. Balancing the increased and competing risks of clotting and bleeding in these patients can be difficult, because management of cancer-associated thrombosis requires anticoagulation despite known increased risks for bleeding. In the context of challenging illustrative cases, this review will describe management approaches to clinical scenarios in which data are sparse: cancer patients with recurrent VTE despite anticoagulation and cancer patients with a new VTE in the setting of severe thrombocytopenia.

Prognostic Significance of Incidental Deep Vein Thrombosis in Patients with Cancer Presenting with Incidental Pulmonary Embolism

In symptomatic acute pulmonary embolism (PE), the presence of deep vein thrombosis (DVT) is a risk factor for 30- and 90-day mortality. In patients with cancer and incidental PE, the prognostic effect of concomitant incidental DVT is unknown. In this retrospective study, we examined the effect of incidental DVT on all-cause mortality in such patients. Adjusted Cox multivariate regression analysis was used for relevant covariates. From January 2010 to March 2018, we included 200 patients (mean age, 65.3 ± 12.4 years) who were followed up for 12.5 months (interquartile range 7.4-19.4 months). Of these patients, 62% had metastases, 31% had concomitant incidental DVT, and 40.1% (n = 81) died during follow-up. All-cause mortality did not increase in patients with DVT (hazard ratio [HR] 1.01, 95% confidence interval [CI] 0.43-2.75, p = 0.855). On multivariate analysis, weight (adjusted HR 0.96, 95% CI 0.92-0.99, p = 0.032), and metastasis (adjusted HR 10.26, 95% CI 2.35-44.9, p = 0.002) were predictors of all-cause mortality. In conclusion, low weight and presence of metastases were associated with all-cause mortality, while presence of concomitant DVT was unrelated to poorer survival.

Mortality risk associated with venous thromboembolism: a systematic review and Bayesian meta-analysis

BACKGROUND

Venous thromboembolism is associated with increased mortality risk in some populations, but how frequently it is a direct cause of death is unclear. We used data from venous thromboembolism prevention trials to evaluate the causal effect of venous thromboembolism reduction on mortality.

METHODS

We did a systematic review and meta-analysis of randomised controlled trials (RCTs) evaluating venous thromboembolism prevention. We searched MEDLINE, Embase, PubMed, and Web of Science starting from Jan 1, 1993, to March 19, 2018. We included studies of patients who were at elevated risk of venous thromboembolism and were randomly assigned to either anticoagulant or antiplatelet therapy versus placebo or no treatment. We excluded studies with an active control agent (which might mitigate the lethality of venous thromboembolism) and those for which mortality data were unavailable. We modelled heterogeneity in a Bayesian framework, taking overall mortality as a primary endpoint, and pulmonary embolism, fatal pulmonary embolism, and major bleeding as secondary endpoints. We focused our analyses on studies reporting statistically significant effects of prevention on venous thromboembolism endpoints. We report treatment effects as median risk ratios (RRs), wherein a null effect equals 1, with 95% credible intervals (CrIs). This meta-analysis was registered with PROSPERO, CRD42018089697.

FINDINGS

From 4229 studies screened, we identified 86 eligible RCTs; 52, with data from over 70 000 patients, were positive, with significantly increased venous thromboembolism risk in patients in control groups versus treatment groups (RR 2·74, 95% CrI 2·32-3·31, p<0·0001). The meta-analysis established that the causal effect of venous thromboembolism prevention on mortality was null (control group mortality was 3391 [9·8%] of 34 537 patients; treatment group mortality was 3498 [9·8%] of 35 795 patients [RR 1·01, 95% CrI 0·97-1·06; p=0·58]) with low heterogeneity (τ 0·02, 95% CrI 0·00-0·07, p=0·89). Patients in control groups had more pulmonary embolism (RR 2·22, 95% CrI 1·78-2·89, p<0·0001) and fatal pulmonary embolism (1·58, 1·14-2·19, p=0·01), but less major bleeding (0·60, 0·47-0·75, p<0·0001) than those in treatment groups. A meta-analysis with the additional 34 negative studies yielded similar results for all endpoints except fatal pulmonary embolism, where evidence of an effect was weaker (1·42, 1·05-1·91, p=0·02).

INTERPRETATION

The perception that venous thromboembolism is a common cause of mortality should be revised considering the null effect of venous thromboembolism prevention on mortality. Our findings call into question the use of composite endpoints in venous thromboembolism-prevention trials and provide rationale for de-escalation trials.

FUNDING

None.

Pulmonary embolism: update on management and controversies

Pulmonary embolism is a common and potentially fatal cardiovascular disorder that must be promptly diagnosed and treated. The diagnosis, risk assessment, and management of pulmonary embolism have evolved with a better understanding of efficient use of diagnostic and therapeutic options. The use of either clinical probability adjusted or age adjusted D-dimer interpretation has led to a reduction in diagnostic imaging to exclude pulmonary embolism. Direct oral anticoagulation therapies are safe, effective, and convenient treatments for most patients with acute venous thromboembolism, with a lower risk of bleeding than vitamin K antagonists. These oral therapeutic options have opened up opportunities for safe outpatient management of pulmonary embolism in selected patients. Recent clinical trials exploring the use of systemic thrombolysis in intermediate to high risk pulmonary embolism suggest that this therapy should be reserved for patients with evidence of hemodynamic compromise. The role of low dose systemic or catheter directed thrombolysis in other patient subgroups is uncertain. After a diagnosis of pulmonary embolism, all patients should be assessed for risk of recurrent venous thromboembolism to guide duration of anticoagulation. Patients with a venous thromboembolism associated with a strong, transient, provoking risk factor can safely discontinue anticoagulation after three months of treatment. Patients with an ongoing strong risk factor, such as cancer, or unprovoked events are at increased risk of recurrent events and should be considered for extended treatment. The use of a risk prediction score can help to identify patients with unprovoked venous thromboembolism who can benefit from extended duration therapy. Despite major advances in the management of pulmonary embolism, up to half of patients report chronic functional limitations. Such patients should be screened for chronic thromboembolic pulmonary hypertension, but only a small proportion will have this as the explanation of their symptoms. In the remaining patients, future studies are needed to understand the pathophysiology and explore interventions to improve quality of life.

A snapshot of cancer-associated thromboembolic disease in 2018-2019: First data from the TESEO prospective registry

BACKGROUND

The ever-growing complexity of cancer-associated thrombosis (CAT), with new antineoplastic drugs and anticoagulants, distinctive characteristics, and decisions with low levels of evidence, justifies this registry.

METHOD

TESEO is a prospective registry promoted by the Spanish Society of Medical Oncology to which 34 centers contribute cases. It seeks to provide an epidemiological description of CAT in Spain.

RESULTS

Participants (N=939) with CAT diagnosed between July 2018 and December 2019 were recruited. Most subjects had advanced colon (21.4%), non-small cell lung (19.2%), and breast (11.1%) cancers, treated with dual-agent chemotherapy (28.4%), monochemotherapy (14.4%), or immune checkpoint inhibitors (3.6%). Half (51%) were unsuspected events, albeit only 57.1% were truly asymptomatic. Pulmonary embolism (PE) was recorded in 571 (58.3%); in 120/571 (21.0%), there was a concurrent deep venous thromboembolism (VTE). Most initially received low molecular weight heparin (89.7%). Suspected and unsuspected VTE had an OS rate of 9.9 (95% CI, 7.3-non-computable) and 14.4 months (95% CI, 12.6-non-computable) (p=0.00038). Six-month survival was 80.9%, 55.9%, and 55.5% for unsuspected PE, unsuspected PE admitted for another reason, and suspected PE, respectively (p<0.0001). The 12-month cumulative incidence of venous rethrombosis was 7.1% (95% CI, 4.7-10.2) in stage IV vs 3.0% (95% CI, 0.9-7.1) in stages I-III. The 12-month cumulative incidence of major/clinically relevant bleeding was 9.6% (95% CI, 6.1-14.0) in the presence of risk factors.

CONCLUSION

CAT continues to be a relevant problem in the era of immunotherapy and targeted therapies. The initial TESEO data highlight the evolution of CAT, with new agents and thrombotic risk factors.

Readmission after inferior vena cava filter placement for acute venous thromboembolism in the United States: Impact of a cancer diagnosis

BACKGROUND

Inferior vena cava filter (IVCF) use is common after a venous thromboembolic event (VTE). Cancer is associated with higher rates of VTEs and is also seen in a significant proportion of patients requiring IVCF. As hospital readmissions remain a frequently scrutinized metric, we sought to evaluate the impact of cancer on hospital-readmission rates and in-hospital outcomes among patients with VTEs who received an IVCF.

METHODS

Leveraging the 2013 to 2014 Nationwide Readmission Database, we identified adult patients presenting with a VTE in the United States and evaluated 30-day readmission rates and readmission in-hospital outcomes postindex-admission. Multivariable logistic regression was used to identify factors associated with readmission after an index-procedure, including traditional and nontraditional cardiovascular risk factors, as well as hospital-level characteristics.

RESULTS

Among the 619 241 patients presenting with a VTE at index-admission, 11.2% of patients received IVCF on index-admission, of which 30.9% had cancer. The 30-day readmission rate amongst IVCF recipients was 15.8% (N = 10 927), and 19.9% amongst those with cancer compared to 13.9% in patients without cancer (P < .001). Moreover, cancer patients had longer lengths of stay in the hospital (4.5 ± 0.2 vs 4.0 ± 0.1 days; P = .02), higher cost of care ($10 900 ± 308 vs $9242 ± 206; P = .007), but no difference in mortality (8.3% vs 6.3%; P = .70) during readmission compared to noncancer patients.

CONCLUSION

Readmission after IVCF placement is common. In patients readmitted after an IVCF implantation, those with cancer have longer hospital stays and higher costs of care. However, in-hospital mortality is similar to those without cancer.

Dose-adjusted enoxaparin thromboprophylaxis in hospitalized cancer patients: a randomized, double-blinded multicenter phase 2 trial

Hospitalized patients with cancer are at an increased risk of developing venous thromboembolism (VTE). The recommendation for routine pharmacologic thromboprophylaxis in hospitalized patients with cancer to prevent VTE is based on extrapolation of results from noncancer cohorts. There are limited data to support the efficacy and safety of fixed-dose low-molecular-weight heparin (LMWH) regimens in high-risk hospitalized patients with cancer. We conducted a randomized, double-blinded, phase 2 trial in hospitalized patients with active cancer at high risk of developing VTE based on Padua risk score. Patients were randomly assigned to fixed-dose enoxaparin (40 mg daily) vs weight-adjusted enoxaparin (1 mg/kg daily) during hospitalization. The primary objectives were to evaluate the safety of dose-adjusted enoxaparin and evaluate the incidence of VTE with fixed-dose enoxaparin. Blinded clinical assessments were performed at day 14, and patients randomly assigned to fixed-dose enoxaparin subsequently underwent a bilateral lower extremity ultrasound. A total of 50 patients were enrolled and randomized. The median weight of patients enrolled in weight-adjusted enoxaparin arm was 76 kg (range, 60.9-124.5 kg). There were no major hemorrhages or symptomatic VTE in either arm. At time of completion of the blinded clinical assessment, there was only 1 incidentally identified pulmonary embolus that occurred in the weight-adjusted arm. In the group randomly assigned to fixed-dose enoxaparin who subsequently underwent surveillance ultrasound, the cumulative incidence of DVT was 22% (90% binomial confidence interval, 0%-51.3%). This phase 2 trial confirms a high incidence of asymptomatic VTE among high-risk hospitalized patients with cancer and that weight-adjusted LMWH thromboprophylaxis is feasible and well-tolerated. This trial was registered at www.clinicaltrials.gov as #NCT02706249.

Impact of ALK Rearrangement on Venous and Arterial Thrombotic Risk in NSCLC

INTRODUCTION

Clinical venous thromboembolism (VTE) risk prediction scores, such as the Khorana Risk Score, perform poorly in NSCLC, possibly because the tumor molecular subtype is omitted. Previous studies suggest a possible increased VTE risk in ALK-rearranged NSCLC, but data are conflicting.

METHODS

We performed a retrospective cohort study of patients with advanced-stage NSCLC diagnosed between 2009 and 2019. Multivariable, time-to-event analyses modeling the risk of first venous or arterial thrombosis in ALK and non-ALK NSCLC groups, controlling for covariates known to impact thrombosis risk (15 in VTE model and 17 in arterial thrombosis model), were performed using Cox proportional hazards regression and competing-risks regression. Multivariable negative binomial regression modeled the total VTE rate.

RESULTS

A total of 422 patients with ALK-rearranged and 385 patients with non-ALK-rearranged NSCLC were included. Patients with an ALK rearrangement were younger, had better performance status, and had lower rates of most thrombotic risk factors but had significantly higher rates of initial VTE (42.7% versus 28.6%, p < 0.0001), recurrent VTE (13.5% versus 3.1%, p < 0.0001), and similar rates of arterial thrombosis (5.0% versus 4.4%, p = 0.71) compared with non-ALK NSCLC. VTE risk attributable to ALK was significant (Cox model: hazard ratio 3.70, [95% confidence interval [CI]: 2.51-5.44, p < 0.001], competing risks: subhazard ratio 3.91 [95% CI: 2.55-5.99, p < 0.001]). Negative binomial modeling revealed higher VTE rates in patients with an ALK rearrangement (incidence rate ratio 2.47 [95% CI: 1.72-3.55, p < 0.001]). The OR for recurrent VTE was 4.85 (95% CI: 2.60-9.52, p < 0.001). Arterial thrombosis risk attributable to ALK was significant (Cox model: hazard ratio 3.15 [95% CI: 1.18-8.37, p = 0.021], competing risks: subhazard ratio 2.80 [95% CI: 1.06-7.43, p = 0.038]).

CONCLUSIONS

In time-to-event analyses controlling for thrombosis risk factors, the ALK rearrangement conferred a fourfold increase in VTE risk and a threefold increase in arterial thrombosis risk in NSCLC. These patients may benefit from pharmacologic thromboprophylaxis.

Incidence of Venous Thromboembolism in Patients With Newly Diagnosed Pancreatic Cancer and Factors Associated With Outcomes

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) is associated with the highest incidence of venous thromboembolism (VTE) of any cancer type. However, little is known about risk factors for VTE or its outcomes in patients with PDAC.

METHODS

We collected data from a prospective, observational study performed at multiple centers in France from May 2014 through November 2018 (the Base Clinico-Biologique de l'Adénocarcinome Pancréatique [BACAP] study) linked to a database of patients with a new diagnosis of PDAC of any stage. Data were collected from 731 patients at baseline and during clinical follow-up or in the event of symptoms. The primary endpoint was the onset of VTE during follow-up. The secondary endpoints were progression-free survival (PFS) and overall survival (OS) times.

RESULTS

During a median follow-up of 19.3 months, 152 patients (20.79%) developed a VTE. The median time from PDAC diagnosis to the onset of VTE was 4.49 months. Cumulative incidence values of VTE were 8.07% (95% confidence interval [CI], 6.31-10.29) at 3 months and 19.21% (95% CI, 16.27-22.62) at 12 months. In multivariate analysis, PDAC primary tumor location (isthmus vs head: hazard ratio [HR], 2.06; 95% CI, 1.09-3.91; P = .027) and stage (locally advanced vs resectable or borderline: HR, 1.66; 95% CI, 1.10-2.51, P = .016; metastatic vs resectable or borderline: HR, 2.50; 95% CI, 1.64-3.79; P < .001) were independent risk factors for the onset of VTE. Patients who developed VTE during follow-up had shorter times of PFS (HR, 1.74; 95% CI, 1.19-2.54; P = .004) and OS (HR, 2.02; 95% CI, 1.57-2.60; P < .001).

CONCLUSION

In an analysis of data from the BACAP study, we found that frequent and early onsets of VTE after diagnoses of PDAC are associated with significant decreases in times of PFS and OS. Studies are needed to determine whether primary prophylaxis of VTE in patients with PDAC will improve morbidity and mortality related to VTE. (ClinicalTrials.gov, Number: clinicaltrials.gov as number NCT02818829).

Anticoagulant treatment for subsegmental pulmonary embolism

BACKGROUND

Acute pulmonary embolism (PE) is a common cause of death, accounting for 50,000 to 200,000 deaths annually. It is the third most common cause of mortality among the cardiovascular diseases, after coronary artery disease and stroke. The advent of multi-detector computed tomographic pulmonary angiography (CTPA) has allowed better assessment of PE regarding visualisation of the peripheral pulmonary arteries, increasing its rate of diagnosis. More cases of peripheral PEs, such as isolated subsegmental PE (SSPE) and incidental PE, have thereby been identified. These two conditions are usually found in patients with few or none of the classic PE symptoms such as haemoptysis or pleuritic pain, acute dyspnoea or circulatory collapse. However, in patients with reduced cardiopulmonary reserve, classic PE symptoms can be found with isolated SSPEs. Incidental SSPE is found casually in asymptomatic patients, usually by diagnostic imaging performed for other reasons (for example routine CT for cancer staging in oncology patients). Traditionally, all PEs are anticoagulated in a similar manner independent of their location, or number and size of the thrombi. It has been suggested that many patients with SSPE may be treated without benefit, increasing adverse events by a possible unnecessary use of anticoagulants. Patients with isolated SSPE, or incidental PE, may have a more benign clinical presentation compared to those with proximal PEs. However, the clinical significance in patients, and their prognosis, needs to be studied to evaluate whether anticoagulation therapy is required. This is the second update of the Cochrane systematic review published in 2014.

OBJECTIVES

To assess the effectiveness and safety of anticoagulation therapy versus control in patients with isolated subsegmental pulmonary embolism (SSPE) or incidental SSPE.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL and AMED databases and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 26 November 2019. We also undertook reference checking to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials of anticoagulation therapy versus control in patients with SSPE or incidental SSPE.

DATA COLLECTION AND ANALYSIS

Two review authors inspected all citations identified to ensure reliable assessment. If relevant studies were identified, we planned for two review authors to independently extract data and to assess the methodological quality of identified trials using the criteria recommended in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We did not identify any studies that met the inclusion criteria.

AUTHORS' CONCLUSIONS

There is no evidence from randomised controlled trials to assess the effectiveness and safety of anticoagulation therapy versus control in patients with isolated subsegmental pulmonary embolism (SSPE) or incidental SSPE. Well-conducted research is required before informed practice decisions can be made.

The effect of catheter-directed thrombolytic use on readmission rates and in-hospital outcomes among cancer patients with venous thromboembolism in the United States

BACKGROUND

Cancer inducing a hypercoagulable state, venous thromboembolism (VTE) remains a leading cause of morbidity and mortality globally. We assessed the impacts of cancer on the likelihood for readmission after a VTE-targeted procedure.

METHODS

We created a new cohort using discharge-level data from all hospitalizations from State Inpatient Databases of geographically dispersed participating states (18-27 states).

RESULTS

In those presenting with VTE during index-admission (619 241), 2.4% patients underwent catheter directed thrombolytic therapy (CDL) on index admission and among those 20.3% had cancer. Moreover, the 30-day readmission rate amongst CDL recipients (10 776 overall) was 14.3% in those with cancer compared to 8.8% in those with no cancer history (P < .0001). Additionally, in-hospital mortality (5.7% vs 1.1%; P = 0.009) and cost-of-care ($11 014 ± 914 vs $10 520 ± 534; P = .04) was significantly higher in cancer compared to noncancer.

CONCLUSION

The use of CDL does not appear to reduce the risk of returning for a VTE-related admission in cancer.

SEOM clinical guideline of venous thromboembolism (VTE) and cancer (2019)

In 2011, the Spanish Society of Medical Oncology (SEOM) first published a clinical guideline of venous thromboembolism (VTE) and cancer. This guideline was updated in 2014, and since then, multiple studies and clinical trials have changed the landscape of the treatment and prophylaxis of VTE in cancer patients. To incorporate the most recent evidence, including data from direct oral anticoagulants (DOACs) randomized clinical trials, SEOM presents a new update of the guideline.

Management of venous thromboembolism in cancer patients: Considerations about the clinical practice guideline update of the American society of clinical oncology

The American Society of Clinical Oncology (ASCO) recently updated their clinical practice guidelines. The most novel aspect of this update is represented by the introduction of DOACs as pharmacological options both for prophylaxis and treatment of VTE in patients with cancer. The heterogeneity of the cancer population in terms of type and stage of the malignancy, presence of comorbidities, and variability in cancer treatments and prognosis represent the major challenge of managing VTE in patients with cancer. The use of VTE prophylaxis is currently recommended in cancer patients admitted to the hospital for an acute illness or reduced mobility, but no sufficient information is available on the risk of bleeding during thromboprophylaxis. Concerning the thromboprophylaxis in ambulatory cancer patients receiving chemotherapy, further refinement of existing risk models or development of new models are needed for improving risk stratification to identify high-risk cancer patients. The updated ASCO guidelines recommend the use of DOACs (edoxaban and rivaroxaban) for treatment of VTE in patients with cancer. However, Major concerns on "real-life" use of DOACs in patients with cancer are highlighted especially for the bleeding risk in patients with gastrointestinal cancers and the potential drug-drug interactions with specific anticancer therapies. CONCLUSIONS: Uncertainties to the updated ASCO guidelines remain concerning a number of indications on prophylaxis and treatment due to the limited evidence available. These limitations determine the low strength of the recommendations. The ongoing studies will contribute to refine the best management of patients with cancer-associated VTE.

Managing the competing risks of thrombosis, bleeding, and anticoagulation in patients with malignancy

The association between malignancy and thrombosis has been recognized for over a century and a half. Patients with cancer have an elevated risk of both initial and recurrent venous thromboembolism (VTE) compared with patients without cancer owing to cancer- and patient-specific factors. Recurrent VTE is common despite anticoagulation, presenting additional management challenges. Patients with cancer also have an increased risk of bleeding when on anticoagulants compared with patients without cancer. This bleeding risk is heightened by the thrombocytopenia common in patients with hematologic malignancies and those treated with intensive myelosuppressive chemotherapy regimens. Despite the advancements in cancer-directed therapy made over the past 15 years, numerous large studies have confirmed that bleeding and VTE recurrence rates remain high in cancer patients. Balancing the increased and competing risks of clotting and bleeding in these patients can be difficult, because management of cancer-associated thrombosis requires anticoagulation despite known increased risks for bleeding. In the context of challenging illustrative cases, this review will describe management approaches to clinical scenarios in which data are sparse: cancer patients with recurrent VTE despite anticoagulation and cancer patients with a new VTE in the setting of severe thrombocytopenia.

Direct oral anticoagulant for the prevention of thrombosis in ambulatory patients with cancer: A systematic review and meta-analysis

BACKGROUND

It is unclear if direct oral anticoagulant (DOAC) is efficacious and safe for prophylaxis of venous thromboembolism (VTE) in ambulatory patients with cancer.

METHODS

We performed a systematic review using EMBASE, MEDLINE, and CENTRAL. Inclusion criteria included adult ambulatory patients with cancer, prophylactic use of DOAC, and randomized controlled trials. Exclusion criteria included pediatric patients, inpatient or postoperative setting, therapeutic indication of DOAC, or non-phase III randomized controlled trial. Two authors screened/reviewed articles and abstracted the data. Meta-analysis was performed using random-effects model. Efficacy outcome included overall and symptomatic VTE incidence during the first 6 months. Safety outcomes included major bleeding and clinically relevant non-major bleeding (CRNMB) incidence during the on-treatment period. Subgroup analysis was performed for intermediate- and high-risk Khorana score.

RESULTS

A total of 202 records were identified and 28 full-text articles were assessed. Two studies with 1415 participants were included for meta-analysis. For DOAC vs placebo, the relative risks for overall and symptomatic VTE incidence by 6 months were 0.56 (0.35-0.89) and 0.58 (0.29-1.13), respectively. The relative risks for major bleeding and CRNMB while on-treatment were 1.96 (0.80-4.82) and 1.28 (0.74-2.20), respectively. Patients with high-risk Khorana score (3+) derived the largest absolute risk reduction of VTE.

CONCLUSIONS

Low-dose DOAC reduces the rate of overall VTE in higher risk cancer patients starting systemic chemotherapy. It may reduce the rate of symptomatic VTE but increase the likelihood of bleeding.

Clinical implications of incidental venous thromboembolism in cancer patients

Introduction

In cancer patients, current guidance suggests similar treatment for incidental and symptomatic venous thromboembolism (VTE), mainly based on retrospective data. We aimed to evaluate anticoagulant therapy in cancer patients with incidental and symptomatic VTE.

Methods

The Hokusai VTE Cancer Study was a randomised controlled trial comparing edoxaban with dalteparin for cancer-associated VTE. The primary outcome was the composite of first recurrent VTE or major bleeding. Secondary outcomes included major bleeding, recurrent VTE and mortality. Outcomes in patients with incidental and symptomatic VTE were evaluated during the 12-month study period.

Results

331 patients with incidental VTE and 679 patients with symptomatic VTE were enrolled, of whom the index event was confirmed by an independent radiologist. Median durations of anticoagulant treatment were 195 and 189 days, respectively. In patients with incidental VTE, the primary outcome occurred in 12.7% of patients, major bleeding in 6.6% of patients and recurrent VTE in 7.9% of patients. Out of the 26 VTE recurrences in patients with incidental VTE, five (31%) were incidental, seven (44%) were symptomatic and four (25%) were deaths for which pulmonary embolism could not be ruled out. In patients with symptomatic VTE, the primary outcome occurred in 13.8% of patients, major bleeding in 4.9% of patients and recurrent VTE in 10.9% of patients. All-cause mortality was similar in both groups.

Conclusion

Clinical adverse outcomes are substantial in both cancer patients with incidental and symptomatic VTE, supporting current guideline recommendations that suggest treating incidental VTE in the same manner as symptomatic VTE.

The Ottawa score performs poorly in cancer patients with incidental pulmonary embolism

BACKGROUND

The Ottawa score was previously developed to predict recurrent venous thromboembolism (VTE) in cancer patients with VTE. The performance of this score in patients with incidental VTE is currently unclear.

AIM

To evaluate the performance of the Ottawa risk score in cancer patients with incidental pulmonary embolism included in an international, prospective, observational cohort study.

METHODS

The score was used to classify patients as high (≥1), intermediate (0), or low risk (≤-1). The discriminative performance of the score was estimated by calculating the cumulative incidence of recurrent VTE for all groups, the time-dependent c-statistic, and the sub-distribution hazard ratio (SHR), using a competing risk approach.

RESULTS

Of the 691 patients for which the Ottawa score could be calculated, 25 (3.6%) had recurrent VTE during 6-month follow-up and 38 (5.5%) during 12-month follow-up. The c-statistics of the continuous score at 6 and 12 months were 0.45 (95% CI, 0.36-0.54) and 0.51 (95% CI, 0.46-0.59), respectively. The 6-month cumulative incidences of recurrent VTE for those at low, intermediate, and high risk were 3.9% (95% CI, 1.5-8.4), 3.6% (95% CI, 1.9-6.2), and 3.6% (95% CI, 1.8-6.5), respectively. A sensitivity analysis restricted to the on-treatment period yielded similar results. None of the Ottawa risk score items were significantly associated with recurrent VTE.

CONCLUSION

In cancer patients with incidental pulmonary embolism, the Ottawa risk score has a poor predictive value for recurrent VTE, which does not support the use of the score in this patient population.