The Reality of VTE: How to Best Address in Cancer Care

Patients undergoing minor transplant, chemotherapy, or transplant should not receive VTE prophylaxis, according to Smith.

Several factors play a role in deciding whether a patient with cancer experiencing venous thromboembolism (VTE) should receive prophylaxis for this type of event, explained Leslie Smith, DNP, RN, APRN-CNS, AOCNS, BMTCN, a clinical nurse specialist in oncology stem cell transplant at the National Institute of Health Clinical Center in Bethesda, Maryland.

“VTE and malignancy, even though patients with have a higher risk of development of VTE, prophylaxis is not recommended as a general rule in the absence of VTE,” said Smith in a presentation during the 2025 School of Nursing Oncology, an event hosted by Physicians’ Education Resource, LLC. “It has not been shown to prolong overall survival.”

What are the risk factors for patients to develop VTE?

VTE appears in 10% of patients with cancer due to procoagulant tumor activity that induces thrombin formation and is in an anatomic location of the tumor.

“We do know that there are certain types of chemotherapies, and especially if you have a patient who is receiving immunomodulatory drugs—lenalidomide (Revlimid), pomalidomide (Pomalyst)—predisposes to the development of clots due to the way these drugs are metabolized in the body, also patients who have major abdominal or pelvic surgeries [that are associated with VTE],” Smith said, adding that patient factors for VTE include obesity, smoking history, and sedentary vs active lifestyles that can be predisposed conditions for blood clots.

Prophylaxis for VTE varies and depends on the patient setting:

• Hospitalized patients:
  • Yes: If patients have decreased mobility and active malignancy in absence of bleeding or other contraindications
  • No: In transplant, minor procedures, or those undergoing chemotherapy
• Outpatient setting:
  • No: Unless their Khorana Score is less than 2 (contraindicated if risk of bleeding or drug interactions)
    • Aspirin is the go-to for patients on immunomodulatory agents
• Surgical patients undergoing major surgery:
  • Yes: Unfractionated heparin or low molecular weight heparin preoperatively, and for 7 to 10 days postoperatively
    • Treatment can extend 4 weeks for patients undergoing abdominal/pelvic surgery with high-risk features
    • Mechanical prophylaxis is not the sole intervention

Prophylactic options for VTE include low molecular weight heparin or direct oral anticoagulants. Smith added that injectable anticoagulants are also an option. Apixaban (Eliquis) or rivaroxaban (Xarelto), “which [are] the most studied in the cancer population, are your go-to choices, but you want to consider the cost. These can be very expensive,” Smith said. “If the patients have a large copay that might be difficult for them to afford these drugs. But are they willing to self-inject at home, or do they have somebody who’s going to give them a low molecular weight heparin injection? And how long is their therapy going to continue?”

What are the current best practices for the management of oncological emergencies?

If a patient currently has VTE, Smith explained that the go-to recommendation is long-term low molecular weight heparin or direct oral anticoagulants. “Generally, you want to continue for 6 months,” Smith said, adding that no warfarin or unfractionated heparin should be administered.

If there is no renal impairment (cancer-related cognitive impairment > 30 mL/min), low molecular weight heparin can be given for the first 5 to 10 days, she concluded.

Reference

Smith L. Oncological emergencies: quick interventions that save lives. Presented at: 2025 School of Nursing Oncology; August 9, 2025; Nashville, TN.