Gynecological Cancer and Venous Thromboembolism: A Narrative Review to Increase Awareness and Improve Risk Assessment and Prevention

The prevention and appropriate management of venous thromboembolism in cancer patients is of paramount importance. However, the literature data report an underestimation of this major problem in patients with gynecological cancers, with an inconsistent venous thromboembolism risk assessment and prophylaxis in this patient setting. This narrative review provides a comprehensive overview of the available evidence regarding the management of venous thromboembolism in cancer patients, focusing on the specific context of gynecological tumors, exploring the literature discussing risk factors, risk assessment, and pharmacological prophylaxis. We found that the current understanding and management of venous thromboembolism in gynecological malignancy is largely based on studies on solid cancers in general. Hence, further, larger, and well-designed research in this area is needed.

Analysis of thromboembolic events in head and neck cancer patients who underwent concurrent chemoradiotherapy with cisplatin

BACKGROUND/AIMS

The study investigated the incidence of thromboembolic events (TEE) in head and neck (H&N) cancer patients who received concurrent chemoradiotherapy (CCRT) with cisplatin, and analyzed the factors affecting TEE occurrence.

METHODS

Two hundred and fifty-seven patients who started CCRT with cisplatin for H&N cancer from January 2005 to December 2019 were analyzed.

RESULTS

TEE occurred in five patients, an incidence rate of 1.9%. The 2-, 4-, and 6-month cumulative incidences of TEE were 0.8%, 1.6%, and 1.9%, respectively. Khorana score was the only factor associated with TEE occurrence (p = 0.010).

CONCLUSION

The incidence of TEE in H&N cancer patients who underwent CCRT with cisplatin was relatively low when compared to other types of cancer. However, patients with a high Khorana score require more careful surveillance for possible TEE occurrence.

Splanchnic vein thrombosis predicts worse survival in patients with advanced pancreatic cancer

INTRODUCTION

Pancreatic cancer is a thrombogenic malignancy with nearly half of venous thrombotic events occurring in the splanchnic circulation. The effect of splanchnic vein thrombosis on mortality in pancreatic cancer is unknown. We studied the effect of splanchnic vein thrombosis on mortality in veterans with advanced pancreatic adenocarcinoma, and explored the association of anticoagulant therapy on mortality and hemorrhage.

METHODS

Using International Classification of Diseases (ICD) codes, we identified eligible patients and outcomes in the Veterans Health Administration database. Using Cox proportional hazards regression, we analyzed the association between splanchnic vein thrombosis and mortality among patients with advanced pancreatic cancer. We used propensity score inverse probability-of-treatment weighting to balance the groups who did and did not receive anticoagulation. To understand the role of anticoagulant therapy, we used Cox proportional hazards regression to analyze mortality and competing risk analysis to assess the risk of hemorrhage.

RESULTS

Of the patients with advanced pancreatic cancer (N = 6164), 122 developed splanchnic vein thrombosis. Splanchnic vein thrombosis was associated with a two-fold increase in mortality, aHR 2.02, 95% CI 1.65-2.47. The finding held true after restricting the analysis to patients undergoing treatment for pancreatic cancer, and after adjusting for immortal time bias by a 30-day landmark analysis. Anticoagulant therapy did not affect mortality (aHR 0.99, 95% CI 0.65-1.51), and increased the risk of hemorrhage (aHR 2.7, 95% CI 1.02-7.07).

CONCLUSION

Splanchnic vein thrombosis predicts worse survival in patients with advanced pancreatic adenocarcinoma. Anticoagulant therapy may not mitigate this increased mortality, and increases the risk of hemorrhage.

Venous thromboembolism and prognosis in cancer

Venous thromboembolism (VTE) is a frequent complication of malignancy, and its incidence has increased markedly in recent years. VTE itself can directly lead to patient mortality, and is the second leading cause of death in patients with cancer. Furthermore, emerging data suggest that activation of coagulation in malignancy is integrally linked with tumor biology, particularly with angiogenesis. The development of the clinical hypercoagulable state is also linked with adverse prognosis in patients with cancer, including patients receiving systemic chemotherapy. This review focuses on the clinical evidence documenting a link between VTE and adverse short-term and long-term prognosis in patients with cancer.

Thromboprophylaxis with low-molecular-weight heparin in medical patients with cancer

Venous thromboembolism (VTE) is a frequent complication of cancer and cancer treatment and is associated with multiple clinical consequences, including recurrent VTE, bleeding, and an increase in the risk of death. Although the risks associated with VTE have been well recognized in surgical cancer patients, there is also considerable and increasing risk in medical cancer patients. VTE risk factors in medical cancer patients include the type and stage of cancer, major comorbid illnesses, current hospitalization, active chemotherapy, hormone therapy, and antiangiogenic agents. Low-molecular-weight heparins (LMWHs) are recommended commonly for the prevention of VTE in hospitalized cancer patients and in higher risk ambulatory cancer patients because of their favorable risk-to-benefit profile. These agents have demonstrated effectiveness in both the primary and secondary prevention of VTE in medical cancer patients. Extended-duration anticoagulant therapy is often recommended to reduce the risk of VTE recurrence in patients with cancer. LMWHs are often used for long-term prophylaxis because of a reduced need for coagulation monitoring, few major bleeding episodes, and once-daily dosing. Despite clinical and practical benefits, a substantial proportion of medical cancer patients do not receive VTE prophylaxis. To improve the appropriate prevention and treatment of VTE in cancer patients, guidelines have been published recently by the American Society of Clinical Oncology and the National Comprehensive Cancer Network. Widespread dissemination and application of these guidelines are encouraged to improve the appropriate use of these agents and to improve clinical outcomes in medical cancer patients at risk for VTE and its complications.

Impact of venous thromboembolism and anticoagulation on cancer and cancer survival

Changes in the hemostatic system and chronic hemostatic activation are frequently observed in patients with cancer, even in the absence of venous thromboembolism (VTE). VTE is a leading cause of death among patients with cancer and contributes to long-term mortality in patients with early as well as advanced-stage cancer. Mounting evidence suggests that components of the clotting cascade and associated vascular factors play an integral part in tumor progression, invasion, angiogenesis, and metastasis formation. Furthermore, there are intriguing in vitro and animal findings that anticoagulants, in particular the low molecular weight heparins (LMWHs), exert an antineoplastic effect through multiple mechanisms, including interference with tumor cell adhesion, invasion, metastasis formation, angiogenesis, and the immune system. Several relatively small randomized controlled clinical trials of anticoagulation as cancer therapy in patients without a VTE diagnosis have been completed. These comprise studies with LMWH, unfractionated heparin, and vitamin K antagonists, with overall encouraging but nonconclusive results and some limitations. Meta-analyses performed for the American Society of Clinical Oncology VTE Guidelines Committee and the Cochrane Collaboration suggest overall favorable effects of anticoagulation on survival of patients with cancer, mainly with LMWH. However, definitive clinical trials have been elusive and questions remain regarding the importance of tumor type and stage on treatment efficacy, the impact of fatal thromboembolic events, optimal anticoagulation therapy, and safety with differing chemotherapy regimens. Although the LMWHs and related agents hold promise for improving outcomes in patients with cancer, additional studies of their efficacy and safety in this setting are needed.