Management and outcomes of cancer patients with venous thromboembolism presenting with thrombocytopenia

[Translation into French and republication of: "Management of cancer-associated thromboembolism in vulnerable population"]

Although all patients with cancer-associated thrombosis (CAT) have a high morbidity and mortality risk, certain groups of patients are particularly vulnerable. This may expose the patient to an increased risk of thrombotic recurrence or bleeding (or both), as the benefit-risk ratio of anticoagulant treatment may be modified. Treatment thus needs to be chosen with care. Such vulnerable groups include older patients, patients with renal impairment or thrombocytopenia, and underweight and obese patients. However, these patient groups are poorly represented in clinical trials, limiting the available data on which treatment decisions can be based. Meta-analysis of data from randomised clinical trials suggests that the relative treatment effect of direct oral factor Xa inhibitors (DXIs) and low molecular weight heparin (LMWH) with respect to major bleeding could be affected by advanced age. No evidence was obtained for a change in the relative risk-benefit profile of DXIs compared to LMWH in patients with renal impairment or of low body weight. The available, albeit limited, data do not support restricting the use of DXIs in patients with TAC on the basis of renal impairment or low body weight. In older patients, age is not itself a critical factor for choice of treatment, but frailty is such a factor. Patients over 70 years of age with CAT should undergo a systematic frailty evaluation before choosing treatment and modifiable bleeding risk factors should be addressed. In patients with renal impairment, creatine clearance should be assessed and monitored regularly thereafter. In patients with an eGFR less than 30mL/min/1.72m2, the anticoagulant treatment may need to be adapted. Similarly, platelet count should be assessed prior to treatment and monitored regularly. In patients with grade 3-4, thrombocytopenia (less than 50,000platelets/μL) treatment with a LMWH at a reduced dose should be considered. For patients with CAT and low body weight, standard anticoagulant treatment recommendations are appropriate, whereas in obese patients, apixaban may be preferred.

Cancer-associated thrombosis in hematologic malignancies

Patients with hematologic malignancies are often complicated not only by severe bleeding due to thrombocytopenia and disseminated intravascular coagulation but also by thromboembolic events, just like in patients with solid cancers, and these events can negatively impact patient outcomes. Nevertheless, the prevention and treatment of cancer-associated thrombosis (CAT) in hematologic malignancies has not been adequately investigated due to the limited size, heterogeneity, and unique pathophysiology of the patient population. This article summarizes the current understanding, risk factors, prediction models, and optimal prevention and treatment strategies of CAT in hematologic malignancies on a disease-by-disease basis, including acute leukemia, lymphoma, myeloma, and myeloproliferative neoplasms. Specific considerations of novel molecular targeted therapeutics introduced in recent years, such as immunomodulatory drugs and tyrosine kinase inhibitors, are also discussed based on the latest clinical trials.

Management of cancer-associated thromboembolism in vulnerable population

Although all patients with cancer-associated thrombosis (CAT) have a high morbidity and mortality risk, certain groups of patients are particularly vulnerable. This may expose the patient to an increased risk of thrombotic recurrence or bleeding (or both), as the benefit-risk ratio of anticoagulant treatment may be modified. Treatment thus needs to be chosen with care. Such vulnerable groups include older patients, patients with renal impairment or thrombocytopenia, and underweight and obese patients. However, these patient groups are poorly represented in clinical trials, limiting the available data, on which treatment decisions can be based. Meta-analysis of data from randomised clinical trials suggests that the relative treatment effect of direct oral factor Xa inhibitors (DXIs) and low molecular weight heparin (LMWH) with respect to major bleeding could be affected by advanced age. No evidence was obtained for a change in the relative risk-benefit profile of DXIs compared to LMWH in patients with renal impairment or of low body weight. The available, albeit limited, data do not support restricting the use of DXIs in patients with CAT on the basis of renal impairment or low body weight. In older patients, age is not itself a critical factor for choice of treatment, but frailty is such a factor. Patients over 70 years of age with CAT should undergo a systematic frailty evaluation before choosing treatment and modifiable bleeding risk factors should be addressed. In patients with renal impairment, creatine clearance should be assessed and monitored regularly thereafter. In patients with an eGFR<30mL/min/1.72m2, the anticoagulant treatment may need to be adapted. Similarly, platelet count should be assessed prior to treatment and monitored regularly. In patients with grade 3-4, thrombocytopenia (<50,000 platelets/μL) treatment with a LMWH at a reduced dose should be considered. For patients with CAT and low body weight, standard anticoagulant treatment recommendations are appropriate, whereas in obese patients, apixaban may be preferred.

Anticoagulation management and related outcomes in patients with cancer-associated thrombosis and thrombocytopenia: A systematic review and meta-analysis

BACKGROUND

Patients with cancer have an increased risk of both venous thromboembolism (VTE) requiring anticoagulation and thrombocytopenia. The optimal management is unclear. We performed a systematic review and meta-analysis to evaluate the outcomes in these patients.

METHODS

We searched MEDLINE, Embase, Scopus, and Cochrane Central Register of Controlled Trials from inception to February 5, 2022. Studies assessing adult patients with cancer-associated thrombosis and platelet count <100 × 10⁹/L were included. Three anticoagulation management strategies were reported: full dose, modified dose, or no anticoagulation. The primary efficacy outcome was recurrent VTE, and the primary safety outcome was major bleeding. The incidence rates of thrombotic and bleeding outcomes by anticoagulation management strategies were descriptive, and were pooled using random effects model and expressed as events per 100 patient-months with associated 95 % confidence intervals (CI).

RESULTS

We included 19 observational cohort studies (N = 1728 patients) in the systematic review, with 10 included in the meta-analysis (N = 707 patients). Approximately 90 % of patients had hematological malignancies, with low-molecular-weight heparin being the main anticoagulant. The rates of recurrent VTE and bleeding complications were high regardless of management strategies - recurrent VTE on full dose: 2.65/100 patient-months (95 % CI 1.62-4.32), modified dose: 3.51/100 patient-months (95 % CI 1.00-12.39); major bleeding on full dose: 4.45/100 patient-months (95 % CI 2.80-7.06), modified dose: 4.16/100 patient-months (95 % CI 2.24-7.74). There was serious risk of bias in all studies.

CONCLUSIONS

Patients with cancer-associated thrombosis and thrombocytopenia have high risks of both recurrent VTE and major bleeding, but current literature is significantly limited to guide the best management.

Cancer Histology and Natural History of Patients with Lung Cancer and Venous Thromboembolism

Simple Summary

Cancer is a widely heterogeneous disease, and the natural history of patients with cancer-associated thrombosis may differ according to the cancer site. Lung cancer is the most common malignancy, and a leading cause of death. A number of studies in the literature suggest that patients with adenocarcinoma may have a worse outcome than those with squamous or other types of lung cancer. The aim of the current study was to assess the potential impact of lung cancer histology on the incidence rates of VTE recurrences, major bleeding, or death appearing during the course of anticoagulation, in patients with lung cancer and VTE. Our findings, obtained from a large series of consecutive patients with lung cancer and VTE (482 patients), reveal important differences between patients with adenocarcinoma vs. other histologies in their outcomes during anticoagulation. This might likely help to design better therapeutic strategies for patients with lung cancer.

Abstract

Background: In patients with lung cancer and venous thromboembolism (VTE), the influence of cancer histology on outcome has not been consistently evaluated. Methods: We used the RIETE registry (Registro Informatizado Enfermedad TromboEmbólica) to compare the clinical characteristics and outcomes during anticoagulation in patients with lung cancer and VTE, according to the histology of lung cancer. Results: As of April 2022, there were 482 patients with lung cancer and VTE: adenocarcinoma 293 (61%), squamous 98 (20%), small-cell 44 (9.1%), other 47 (9.8%). The index VTE was diagnosed later in patients with squamous cancer than in those with adenocarcinoma (median, 5 vs. 2 months). In 50% of patients with adenocarcinoma, the VTE appeared within the first 90 days since cancer diagnosis. During anticoagulation (median 106 days, IQR: 45–214), 14 patients developed VTE recurrences, 15 suffered major bleeding, and 218 died: fatal pulmonary embolism 10, fatal bleeding 2. The rate of VTE recurrences was higher than the rate of major bleeding in patients with adenocarcinoma (11 vs. 6 events), and lower in those with other cancer types (3 vs. 9 events). On multivariable analysis, patients with adenocarcinoma had a non-significantly higher risk for VTE recurrences (hazard ratio [HR]: 3.79; 95%CI: 0.76–18.8), a lower risk of major bleeding (HR: 0.29; 95%CI: 0.09–0.95), and a similar risk of mortality (HR: 1.02; 95%CI: 0.76–1.36) than patients with other types of lung cancer. Conclusions: In patients with lung adenocarcinoma, the rate of VTE recurrences outweighed the rate of major bleeding. In patients with other lung cancers, it was the opposite.

EHA Guidelines on Management of Antithrombotic Treatments in Thrombocytopenic Patients With Cancer

In cancer patients, thrombocytopenia can result from bone marrow infiltration or from anticancer medications and represents an important limitation for the use of antithrombotic treatments, including anticoagulant, antiplatelet, and fibrinolytic agents. These drugs are often required for prevention or treatment of cancer-associated thrombosis or for cardioembolic prevention in atrial fibrillation in an increasingly older cancer population. Data indicate that cancer remains an independent risk factor for thrombosis even in case of thrombocytopenia, since mild-to-moderate thrombocytopenia does not protect against arterial or venous thrombosis. In addition, cancer patients are at increased risk of antithrombotic drug-associated bleeding, further complicated by thrombocytopenia and acquired hemostatic defects. Furthermore, some anticancer treatments are associated with increased thrombotic risk and may generate interactions affecting the effectiveness or safety of antithrombotic drugs. In this complex scenario, the European Hematology Association in collaboration with the European Society of Cardiology has produced this scientific document to provide a clinical practice guideline to help clinicians in the management of patients with cancer and thrombocytopenia. The Guidelines focus on adult patients with active cancer and a clear indication for anticoagulation, single or dual antiplatelet therapy, their combination, or reperfusion therapy, who have concurrent thrombocytopenia because of either malignancy or anticancer medications. The level of evidence and the strength of the recommendations were discussed according to a Delphi procedure and graded according to the Oxford Centre for Evidence-Based Medicine.

2022 international clinical practice guidelines for the treatment and prophylaxis of venous thromboembolism in patients with cancer, including patients with COVID-19

The International Initiative on Thrombosis and Cancer is an independent academic working group of experts aimed at establishing global consensus for the treatment and prophylaxis of cancer-associated thrombosis. The 2013, 2016, and 2019 International Initiative on Thrombosis and Cancer clinical practice guidelines have been made available through a free, web-based mobile phone application. The 2022 clinical practice guidelines, which are based on a literature review up to Jan 1, 2022, include guidance for patients with cancer and with COVID-19. Key recommendations (grade 1A or 1B) include: (1) low-molecular-weight heparins (LMWHs) for the initial (first 10 days) treatment and maintenance treatment of cancer-associated thrombosis; (2) direct oral anticoagulants for the initial treatment and maintenance treatment of cancer-associated thrombosis in patients who are not at high risk of gastrointestinal or genitourinary bleeding, in the absence of strong drug-drug interactions or of gastrointestinal absorption impairment; (3) LMWHs or direct oral anticoagulants for a minimum of 6 months to treat cancer-associated thrombosis; (4) extended prophylaxis (4 weeks) with LMWHs to prevent postoperative venous thromboembolism after major abdominopelvic surgery in patients not at high risk of bleeding; and (5) primary prophylaxis of venous thromboembolism with LMWHs or direct oral anticoagulants (rivaroxaban or apixaban) in ambulatory patients with locally advanced or metastatic pancreatic cancer who are treated with anticancer therapy and have a low risk of bleeding.

Association between platelets and in-hospital mortality in critically ill patients with tumours: a retrospective cohort study

OBJECTIVES

Platelet count is an independent predictor of mortality in patients with cancer. It remains unknown whether the platelet count is related to in-hospital mortality in severely ill patients with tumours.

DESIGN

A retrospective study based on a dataset from a multicentre cohort.

SETTING

This was a secondary analysis of data from one Electronic Intensive Care Unit Collaborative Research Database survey cycle (2014-2015).

PARTICIPANTS

The data pertaining to severely ill patients with tumours were collected from 208 hospitals located across the USA. This study initially a total of 200 859 participants. After the population was limited to patients with combined tumours and platelet deficiencies, the remaining 2628 people were included in the final data analysis.

PRIMARY AND SECONDARY OUTCOME MEASURES

The main measure was the platelet count, and the main outcome was in-hospital mortality.

RESULTS

After adjustment for the covariates, the platelet count had a curvilinear relationship with in-hospital mortality (p<0.001). The first inflection point was 18.4 (per 10 change). On the left side of the first inflection point (platelet count ≤184 'x10ˆ9/L), an increase of 10 in the platelet count was negatively associated with in-hospital mortality (OR 0.92, 95% CI 0.89 to 0.95, p<0.001). The second inflection point was 44.5 (per 10 change). Additional increases of 10 in the platelet count thereafter were positively associated with hospital mortality (OR 1.13, 95% CI 1.00 to 1.28, p=0.0454). The baseline platelet count was in the range of 184 'x10ˆ9/L-445 'x10ˆ9/L(p=0.0525), and the hospital mortality was lower than the baseline platelet count in other ranges.

CONCLUSIONS

The relationship between platelet count and in-hospital mortality in critically ill patients with tumours was curvilinear. The lowest in-hospital mortality was associated with platelet count between 184 'x10ˆ9/Land 445 'x10ˆ9/L. This indicates that both high and low platelet count should receive attention in clinical practice.

Outcome of cancer-associated venous thromboembolism is more favorable among patients with hematologic malignancies than in those with solid tumors

BACKGROUND

The natural history of patients with hematologic cancer and venous thromboembolism (VTE) has not been consistently evaluated. We aimed to compare the rates of symptomatic recurrent VTE, major bleeding or death during anticoagulant therapy in patients with VTE associated to hematologic vs. solid cancers.

METHODS

Consecutive patients with active cancer recruited in RIETE were evaluated. Their baseline characteristics, treatments and outcomes during the course of anticoagulation were compared. Univariate and multivariate competing-risk analysis were performed.

RESULTS

As of December 2020, 16,694 patients with cancer and VTE were recruited. Of these, 1,062 (6.4%) had hematologic cancers. Hematologic patients were less likely to initially present with pulmonary embolism (48% vs. 63%) and more likely with upper-extremity deep vein thrombosis (25% vs. 18%). They also were more likely to have severe thrombocytopenia at baseline (5.6% vs. 0.7%) or to receive chemotherapy (67% vs. 41%). During the course of anticoagulation (median, 150 vs. 127 days), 1,071 patients (6.4%) developed VTE recurrences, 806 (4.8%) suffered major bleeding and 4,136 (24.8%) died. Patients with hematologic cancers had lower rates of recurrent VTE (rate ratio [RR]: 0.73; 95% confidence interval [CI]: 0.56-0.95), major bleeding (RR: 0.72; 95%CI: 0.53-0.98) or all-cause death (RR: 0.49; 95%CI: 0.41-0.57) than those with solid cancers. Patients with multiple myeloma showed the best outcomes.

CONCLUSIONS

Patients with hematologic cancers, particularly multiple myeloma, and VTE had better outcomes than those with solid cancers. These findings are relevant for the interpretation of previous clinical trials and the design of future studies.

Prediction of Major Bleeding in Anticoagulated Patients for Venous Thromboembolism: Comparison of the RIETE and the VTE-BLEED Scores

The performance of validated bleeding risk scores in patients with venous thromboembolism (VTE) could be different depending on the time after index event or the site of bleeding. In this study we compared the "classic" Registro Informatizado de Enfermedad TromboEmbólica (RIETE) score and the more recently developed VTE-BLEED score for the prediction of major bleeding in patients under anticoagulant therapy in different time intervals after VTE diagnosis. Out of 82,239 patients with acute VTE, the proportion of high-risk patients according to the RIETE and VTE-BLEED scores was 7.1 and 62.3%, respectively. The performance of both scores across the different study periods (first 30 days after VTE diagnosis, days 31-90, days 91-180, and days 181-360) was similar, with areas under the receiving operating characteristics (ROC) curve (AUC) ranging between 0.69 and 0.72. However, the positive predictive values were low, ranging between 0.6 and 3.9 (better for early major bleeding than for later periods). A sensitivity analysis limited to patients with unprovoked VTE showed comparable results. Both scores showed a trend toward a better prediction of extracranial than intracranial major bleeding, the RIETE score resulting more useful for early extracranial bleeding and the VTE-BLEED for late intracranial hemorrhages. Our study reveals that the usefulness of available bleeding scores may vary depending on the characteristics of the patient population and the time frame evaluated. Dynamic scores could be more useful for this purpose.

Current status of treatment of cancer-associated venous thromboembolism

Patients with cancer are prone to develop venous thromboembolism (VTE) that is the second leading cause of mortality among them. Cancer patients with VTE may encounter higher rates of VTE recurrence and bleeding complications than patients without cancer. Treatment of established VTE is often complex in patients with cancer. Treatment of cancer-associated VTE basically comprises initial treatment, long-term treatment, treatment within 6 months, treatment beyond 6 months, treatment of recurrent VTE, and treatment in special situations. Decision of antithrombotic therapy, selection of anticoagulants, duration of anticoagulation, decision of adjuvant therapy, and adjustment of regimen in special situations are the major problems in the treatment of cancer-associated VTE. Therapeutic anticoagulation is the key of the key in the treatment of cancer-associated VTE. In addition to the efficacy and safety of low-molecular-weight heparin (LMWH) that has been fully demonstrated, direct oral anticoagulants (DOACs) are increasingly showing its advantages along with the accompanying concern in the treatment of cancer-associated VTE. The latest ASCO, ITAC and NCCN guidelines agree with each other on most aspects with respect to the treatment of cancer-associated VTE, whereas differ on a few issues. Encompassing recent randomized controlled trials, clinical trials, and meta-analyses, as well as the comparison of the latest authoritative guidelines including the NCCN, ASCO, and ITAC guidelines in this field, the objective of this review is to present current overview and recommendations for the treatment of cancer-associated VTE.

Challenges and Advances in Managing Thrombocytopenic Cancer Patients

Cancer patients have varying incidence, depth and duration of thrombocytopenia. The mainstay of managing severe chemotherapy-induced thrombocytopenia (CIT) in cancer is the use of platelet transfusions. While prophylactic platelet transfusions reduce the bleeding rate, multiple unmet needs remain, such as high residual rates of bleeding, and anticancer treatment dose reductions/delays. Accordingly, the following promising results in other settings, antifibrinolytic drugs have been evaluated for prevention and treatment of bleeding in patients with hematological malignancies and solid tumors. In addition, Thrombopoeitin receptor agonists have been studied for two major implications in cancer: treatment of severe thrombocytopenia associated with myelodysplastic syndrome and acute myeloid leukemia; primary and secondary prevention of CIT in solid tumors in order to maintain dose density and intensity of anti-cancer treatment. Furthermore, thrombocytopenic cancer patients are often prescribed antithrombotic medication for indications arising prior or post cancer diagnosis. Balancing the bleeding and thrombotic risks in such patients represents a unique clinical challenge. This review focuses upon non-transfusion-based approaches to managing thrombocytopenia and the associated bleeding risk in cancer, and also addresses the management of antithrombotic therapy in thrombocytopenic cancer patients.

Challenging anticoagulation cases: Cancer-associated venous thromboembolism and chemotherapy-induced thrombocytopenia - A case-based review of clinical management

Patients with cancer undergoing chemotherapy are at risk of thrombocytopenia. The co-incidence of cancer-associated venous thromboembolism (VTE) and thrombocytopenia is a frequent complication in patients with cancer. Especially in certain tumour entities at high VTE risk, chemotherapeutic agents with myelosuppressive effects are part of the standard of care. The management of cancer-associated VTE in the setting of chemotherapy-induced thrombocytopenia is challenging, in the absence of evidence from high-quality studies. Thrombocytopenia is associated with both increased risk of recurrent VTE and risk of bleeding during anticoagulation. In this case-based concise review, we aimed at summarizing available literature and expert consensus guidance on the treatment of cancer-associated VTE in patients with chemotherapy-induced thrombocytopenia.