Frequency, clinical pattern and outcome of thrombosis in cancer patients in Saudi Arabia

The Role of Direct Oral Anticoagulants in the Treatment of Cancer-Associated Venous Thromboembolism: Review by Middle East and North African Experts

Venous thromboembolism is a leading cause of morbidity and mortality in patients with active cancer who require anticoagulation treatment. Choice of anticoagulant is based on careful balancing of the risks and benefits of available classes of treatment: vitamin K antagonists, low-molecular-weight heparin (LMWH), and direct oral anticoagulants (DOACs). Results from randomized controlled trials have shown the consistent efficacy of DOACs versus LMWH in the treatment of cancer-associated venous thromboembolism (VTE). However, increased major gastrointestinal bleeding was observed for edoxaban and rivaroxaban, but not apixaban, compared with LMWH dalteparin. Most guidelines recommend DOACs for the treatment of cancer-associated VTE in patients without gastrointestinal or genitourinary cancer, and with considerations for renal impairment and drug-drug interactions. These updates represent a major paradigm shift for clinicians in the Middle East and North Africa. The decision to prescribe a DOAC for a patient with cancer is not always straightforward, particularly in challenging subgroups of patients with an increased risk of bleeding. In patients with gastrointestinal malignancies who are at high risk of major gastrointestinal bleeds, apixaban may be the preferred DOAC; however, caution should be exercised if patients have upper or unresected lower gastrointestinal tumors. In patients with gastrointestinal malignancies and upper or unresected lower gastrointestinal tumors, LMWH may be preferred. Vitamin K antagonists should be used only when DOACs and LMWH are unavailable or unsuitable. In this review, we discuss the overall evidence for DOACs in the treatment of cancer-associated VTE and provide treatment suggestions for challenging subgroups of patients with cancer associated VTE.

The Saudi Consensus for the Management of Cancer-Associated Thromboembolism: A Modified Delphi-Based Study

Background  Cancer is a well-known risk factor of preventable thromboembolic disease. This study aims to provide guidance on the prevention and management of cancer-associated thrombosis (CT) that tailors prophylactic and therapeutic options for medical and surgical oncology patients presenting to health care settings in Saudi Arabia. Methods  The present consensus was developed in concordance with the modified Delphi-based approach, which incorporates a face-to-face meeting between two voting rounds to gain experts' feedback on the proposed statements. All experts were either oncologists, hematologists, or hemato-oncologist with an active clinical and research profile in hemato-oncology. Results  The experts highlighted that the comparatively high incidence of inherited thrombophilia among the Saudi population may account for a higher CT burden in the Kingdom than in other parts of the world. However, due to the lack of literature that assesses CT in Saudi Arabia, primary venous thromboembolism prophylaxis should be tailored according to a valid risk assessment of cancer patients and should be implemented in routine practice. For hospitalized medical oncology patients, the experts agreed that prophylaxis with low-molecular-weight heparin (LMWH) should be offered, regardless of the presence of acute illness. For ambulatory medical oncology patients, LMWH or direct oral anticoagulants (DOACs) prophylaxis should be offered for high-risk patients. Concerning surgical patients, they agreed that all oncology patients undergoing surgery should be offered thromboprophylaxis. In terms of secondary prophylaxis, the experts recommended continuing a prophylactic dose of anticoagulant (LMWH or DOAC), for an appropriate period depending on the cancer type and stage. Finally, they also provided a set of statements on management of CT in Saudi Arabia. Conclusion  The present modified Delphi-based study combined the best available evidence and clinical experience with the current health care policies and settings in Saudi Arabia to build a consensus statement on the epidemiology, prevention, and management of CT.

Characteristics and outcomes of cancer patients who develop pulmonary embolism: A cross‑sectional study

Pulmonary embolism (PE), along with deep vein thrombosis, are collectively known as venous thromboembolism (VTE). Predisposing factors for PE include post-operative conditions, pregnancy, cancer and an advanced age; of note, a number of genetic mutations have been found to be associated with an increased risk of PE. The association between cancer and VTE is well-established, and cancer patients present a higher risk of a thrombotic event compared to the general population. In addition, PE is a significant cause of morbidity and mortality among cancer patients. The aim of the present study was to illustrate the clinical characteristics, laboratory findings, radiology features and outcomes of cancer patients who developed PE, collected from an anticancer hospital. For this purpose, adult cancer patients diagnosed with PE by imaging with computed tomography pulmonary angiography were enrolled. The following data were recorded: Demographics, comorbidities, type of cancer, time interval between cancer diagnosis and PE occurrence, the type of therapy received and the presence of metastases, clinical signs and symptoms, predisposing factors for PE development, laboratory data, radiological findings, electrocardiography findings, and the type of therapy received for PE and outcomes in a follow-up period of 6 months. In total, 60 cancer patients were enrolled. The majority of the cancer patients were males. The most common type of cancer observed was lung cancer. The majority of cases of PE occurred within the first year from the time of cancer diagnosis, while the majority of patients had already developed metastases. In addition, the majority of cancer patients had received chemotherapy over the past month, while they were not receiving anticoagulants and had central obstruction. A large proportion of patients had asymptomatic PE. The in-hospital mortality rate was 13.3% and no relapse or mortality were observed during the follow-up period. The present study demonstrates that elevated levels of lactic acid and an increased platelet count, as well as low serum levels of carcinoembryonic antigen, albumin and D-dimer, may be potential biomarkers for asymptomatic PE among cancer patients.

The association between two genetic polymorphisms in ITGB3 and increase risk of venous thromboembolism in cancer patients in Eastern Province of Saudi Arabia

Venous thromboembolism (VTE) is one of the major complications in most cancer patients leading to poor prognosis and short survival. Several common clinical risk factors coexist in cancer patients are used as risk predictive biomarkers to help in the management and prevention of VTE. These include cancer site and stage, chemotherapy regimen and elevated biological markers. However, Genetic polymorphisms in genes controlling coagulation and fibrinolysis are significantly associated with VTE if detected, then they might be more sensitive individual predictive biomarkers for VTE risk assessment. This study was conducted to evaluate the association between ITGB3 rs3809865 and rs5918 with VTE risk as well as monitor the effect of VTE on overall survival of these cancer patients. In this retrospective case-control study, 195 cancer patients' formalin-fixed paraffin embedded tissue (FFPE) samples were collected (controls n = 157, case n = 38) using the stored data through Jan 2010 to Sep 2018 from King Fahad Specialist Hospital in Dammam. Samples were genotyped using TaqMan genotyping assay, then logistic regression analysis and Chi-square were used to predict the association between risk factors and VTE. Survival Comparison was tested by the log-rank test. Genetic polymorphisms in ITGB3 (rs3809865 and rs5918) found not to be associated with VTE increasing risk in cancer patients (p>0.05). While the advanced stage was potentially increasing the risk of VTE events (OR 5.1 CI 2.01-12.9p = 0.001). Patients with VTE showed a poor overall survival reflected by the median survival rate of only three years compared to seven years for cancer patients without VTE. This study highlighted the potential influence of VTE on prognosis and survival of cancer patients and raised the importance of exploring risk predictive biomarkers in our population. This will improve the risk prediction biomarkers leading to implementing safe and effective thrombosis prophylaxis strategies.

Incidental pulmonary embolism in oncologic patients-a systematic review and meta-analysis

Purpose

Incidental pulmonary embolism (IPE) is a common finding on computed tomography (CT). IPE is frequent in oncologic patients undergoing staging CT. The aim of this analysis was to provide the pooled frequency of IPE and frequencies of IPE in different primary tumors.

Methods

MEDLINE, SCOPUS, and EMBASE databases were screened for studies investigating frequency of IPE in oncologic staging CT up to February 2020. Overall, 12 studies met the inclusion criteria and were included into the present study.

Results

The pooled analysis yielded a total of 28,626 patients. IPE was identified in 963 patients (3.36%, 95% CI = 3.15; 3.57). The highest frequency was found in prostate cancer (8.59%, 95%CI = 3.74; 13.44), followed by hepatobiliary carcinoma (6.07%, 95%CI = 3.09; 9.05) and pancreatic cancer (5.65%, 95%CI = 3.54; 7.76). The lowest frequencies were identified in tumors of male reproductive organs (0.79%, 95%CI = 0.21; 1.37) and hematological diseases (1.11% 95%CI = 0.74; 1.48).

Conclusion

The overall frequency of IPE in oncologic patients was 3.36%. There are considerable differences in regard to primary tumors with the highest frequency in prostate cancer and pancreatic and hepatobiliary carcinomas.

Impact of thrombosis on standard treatment in solid tumors

INTRODUCTION

Malignancy leading to a hypercoagulable state is a well established concept. The reported frequency of venous thrombotic events in cancer patients is 5-8%. There is limited data on the influence of thrombosis on treatment decisions in solid tumors.

METHODS

A retrospective audit of all cases of thrombosis developing in newly diagnosed solid tumors from 1st January 2011 to 31st December 2014 was performed. Changes in treatment decisions for malignancy (deferral of surgery/chemotherapy, changes in the planned course of chemotherapy or changes in the planned dates of chemotherapy) after the documentation of thrombosis were noted.

RESULTS

A total of 11,796 solid tumor cases were registered. 61 patients with thrombosis (0.52%) were identified. In 14 patients(23%), treatment decisions for malignancy had to be changed after the occurrence of thrombosis. 2 patients were deferred surgery, 9 could not undergo chemotherapy according to planned schedules, and 3 were deferred chemotherapy. In survival analysis by multivariate model, stage (p=0.01) and ECOG performance status (p=0.01) significantly predicted survival whereas thrombus location (p=0.09), symptomatic thrombosis (p=0.06), and age (p=0.19) did not.

CONCLUSIONS

Frequency of thrombosis in solid tumors in our centre was less compared to previous reports. There was a significant deviation (nearly one fourth patients) from standard of treatment for malignancy after the development of thrombosis. Survival of patients who developed thrombosis did not significantly vary depending on location of thrombosis or whether it is symptomatic or not.

Prophylaxis and treatment of venous thromboembolism in patients with cancer: the Saudi clinical practice guideline

BACKGROUND AND OBJECTIVES

Venous thromboembolism (VTE) is commonly encountered in the daily clinical practice. Cancer is an important VTE risk factor. Proper thromboprophylaxis is key to prevent VTE in patients with cancer, and proper treatment is essential to reduce VTE complications and adverse events associated with the therapy.

DESIGN AND SETTINGS

As a result of an initiative of the Ministry of Health of Saudi Arabia, an expert panel led by the Saudi Association for Venous Thrombo-Embolism (a subsidiary of the Saudi Thoracic Society) and the Saudi Scientific Hematology Society with the methodological support of the McMaster University working group produced this clinical practice guideline to assist health care providers in evidence-based clinical decision-making for VTE prophylaxis and treatment in patients with cancer.

METHODS

Six questions related to thromboprophylaxis and antithrombotic therapy were identified and the corresponding recommendations were made following the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach.

RESULTS

Question 1. Should heparin versus no heparin be used in outpatients with cancer who have no other therapeutic or prophylactic indication for anticoagulation?

RECOMMENDATION

For outpatients with cancer, the Saudi Expert Panel suggests against routine thromboprophylaxis with heparin (weak recommendation; moderate quality evidence).Question 2. Should oral anticoagulation versus no oral anticoagulation be used in outpatients with cancer who have no other therapeutic or prophylactic indication for anticoagulation?

RECOMMENDATION

For outpatients with cancer, the Saudi Expert Panel recommends against thromboprophylaxis with oral anticoagulation (strong recommendation; moderate quality evidence).Question 3. Should parenteral anticoagulation versus no anticoagulation be used in patients with cancer and central venous catheters?

RECOMMENDATION

For outpatients with cancer and central venous catheters, the Saudi Expert Panel suggests thromboprophylaxis with parenteral anticoagulation (weak recommendation; moderate quality evidence).Question 4. Should oral anticoagulation versus no anticoagulation be used in patients with cancer and central venous catheters?

RECOMMENDATION

For outpatients with cancer and central venous catheters, the Saudi Expert Panel suggests against thromboprophylaxis with oral anticoagulation (weak recommendation; low quality evidence).Question 5. Should low-molecular-weight heparin versus unfractionated heparin be used in patients with cancer being initiated on treatment for venous thromboembolism?

RECOMMENDATION

In patients with cancer being initiated on treatment for venous thromboembolism, the Saudi Expert Panel suggests low-molecular-weight heparin over intravenous unfractionated heparin (weak; very low quality evidence).Question 6. Should heparin versus oral anticoagulation be used in patients with cancer requiring long-term treatment of VTE?

RECOMMENDATION

In patients with metastatic cancer requiring long-term treatment of VTE, the Saudi Expert Panel recommends low-molecular-weight heparin (LMWH) over vitamin K antagonists (VKAs) (strong recommendation; moderate quality evidence). In patients with non-metastatic cancer requiring long-term treatment of venous thromboembolism, the Saudi Expert Panel suggests LMWH over VKA (weak recommendation; moderate quality evidence).

Can megestrol acetate induce thrombosis in advanced oncology patients receiving chemotherapy?

BACKGROUND

Megestrol acetate (MA) is a steroid origin medicine often used for control of cachexia in oncologic palliative care. Thrombosis is a common problem in oncology patients. One question is whether MA can cause thrombosis. This retrospective, registry-based analysis was therefore conducted to assess thrombotic processes in oncology patients using MA concurrent with chemotherapy.

MATERIALS AND METHODS

Data on oncology patients at the metastatic stage using MA were obtained from the archives of our center. Outcomes of patients were evaluated for thromboembolic events (VTEs) during treatment.

RESULTS

Ninety-seven oncology patients with a median age of 62 (33-84) years were included. During the median follow-up of 17 months, 58 (59.8%) died leaving 39 (31.2%) still alive. Median overall survival (OS) was 19 months (6-180). Mean time of MA use was 8.69 months(±3.53), with a median dose of 160mg (range 160-480mg). Eleven VTEs were detected after MA use, 4 of these in pancreatic cancer cases. The patients with thrombosis non-significantly had worse OS, than those without thrombosis (p=0.106).

CONCLUSIONS

This trial revealed that the 11.3% of all patients developed thrombosis,who had been treated with MA and chemotherapy concomittantly. There was no statistically significant difference regarding to occurrence of thrombotic process, among the patients receiving different chemotherapy regimens with MA concomittantly. Pancreatic cancer seemed to be related to thrombosis rather than MA use.