Thrombosis research from ASH 2020: Khorana score falls short in cancer study, factors predict VTE in cancer patients with COVID-19, and antithrombotics don’t affect severe COVID outcomes

Three studies revealed new findings on thrombosis in patients with cancer and/or COVID-19. These studies were presented at the 2020 annual meeting of the American Society of Hematology.

One study suggested the Khorana score may be ineffective for predicting venous thromboembolism (VTE) in cancer patients. Another study revealed factors that can predict VTE in patients with cancer and COVID-19. And a third study indicated that antithrombotic agents don’t improve outcomes in patients with severe COVID-19. 

Kristen M. Sanfilippo, MD, of Washington University, St. Louis, reviews these studies with host David H. Henry, MD, in this episode.

Abstract 202: Performance of Khorana Score to Predict One-Year Risk of Venous Thromboembolism in Over Two Million Patients With Cancer. https://bit.ly/3oCHOfQ.

• The study included 2,112,260 patients with cancer.
• At 1 year after diagnosis, 227,170 (10.8%) patients had developed VTE.
• The Khorana score was a weak to modest predictor of the 1-year risk of VTE (area under the curve, 0.565; 95% confidence interval, 0.564-0.566).

Abstract 204: Incidence of and Risk Factors for Venous Thromboembolism Among Hospitalized Patients With Cancer and COVID-19: Report From the COVID-19 and Cancer Consortium (CCC19) Registry. https://bit.ly/38waPnX.

• The study included 1,813 hospitalized patients with COVID-19 and cancer who were enrolled in the CCC19 registry.
• Patients had an increased risk of VTE if they had received anticancer therapy in the last 3 months (odds ratio, 1.63), had active disease (OR, 1.25 for stable/responding disease and 1.67 for progressing disease), had a cancer subtype with a high VTE risk (OR, 1.57 for high risk and 3.42 for very high risk), or were admitted to the ICU within 48 hours of hospitalization (OR, 2.38).
• Patients had a reduced risk of VTE if they received preadmission anticoagulant (OR, 0.80) or antiplatelet therapy (OR, 0.71).
• The researchers said this information will aid the development of a risk prediction tool for VTE in hospitalized patients with cancer and COVID-19.
• For more information on the CCC19 registry, listen to the Blood & Cancer episode, “Studying cancer patients with COVID-19: NCCAPS and CCC19.” https://bit.ly/39lB0x0.

Abstract 206: Anticoagulant and Antiplatelet Use not Associated With Improvement in Severe Outcomes in COVID-19 Patients. https://bit.ly/3bvHqvV.

• This retrospective study included 28,076 patients with confirmed COVID-19 – 1,024 of whom were on antiplatelet agents, anticoagulants, or both.
• Chronic anticoagulant or antiplatelet use was not associated with a significantly lower risk of VTE (OR, 1.44), emergency department visit (OR, 0.94), ICU stay (OR, 0.87), or death (OR, 0.91).
• However, anticoagulant or antiplatelet use was associated with a decreased risk of ventilator use (OR, 0.72).
• Overall, these findings suggest chronic anticoagulant or antiplatelet use don't mitigate disease severity in COVID-19 patients, the researchers concluded.

The session in which these abstracts were presented is entitled, “904. Outcomes Research – Non-Malignant Conditions: Venous Thromboembolism Associated With Cancer and/or COVID-19,” and details can be found here: https://bit.ly/39olwIl.

Data in some of the abstracts differ from data presented at the meeting.

Disclosures

Dr. Sanfilippo disclosed relationships with Covington & Burling, Luther & Associate