Performance of Khorana Risk Score for Prediction of Venous Thromboembolism in Patients With Hepatocellular Carcinoma

Abstract

Cancer-associated venous thromboembolism (VTE) is one of the leading causes of mortality and morbidity among patients with malignancy. The Khorana risk score (KRS) is currently the best validated risk assessment model to stratify risks of VTE development in ambulatory patients with cancer. In the current study, we assessed the performance of KRS in patients with hepatocellular carcinoma (HCC). We retrospectively analyzed patients with diagnosis of HCC (screened by International Classification of Diseases [ ICD-9] and ICD-10 code, confirmed with radiographic examination and/or histopathology) at a large public hospital over 15 years (January 2000 through July 2015). Cases with VTE were identified through radiographic examination and blindly adjudicated. Khorana risk score was calculated for each patient, and its association with VTE development and mortality was assessed. Among 270 patients with HCC, 16 (5.9%) cases of VTE were identified, including 7 (43.8%) pulmonary embolism, 4 (25%) peripheral deep vein thrombosis, and 6 (37.5%) intra-abdominal thrombosis. One hundred eighty-four (68.1%) patients had a KRS of 0 and 86 (31.9%) patients had a KRS >0. Most of the thrombotic (n = 9, 56%) events occurred in the low-risk group. In univariate analysis, only prechemotherapy leukocyte count equal to or greater than 11 000/μL was statistically significant in the prediction of VTE incidence. After adjusting for confounding factors in multivariate analysis, KRS >0 was not predictive of VTE (hazard ratio [HR] = 1.83, 95% confidence interval [CI] = 0.81-4.15, P = .15) or mortality (HR = 1.61, 95% CI = 0.92-2.81, P = .09). Khorana risk score did not predict VTE development or mortality in patients with HCC. Design of HCC-specific risk assessment model for VTE development is necessary.

Evaluation of the ThroLy score for the prediction of venous thromboembolism in newly diagnosed patients treated for lymphoid malignancies in clinical practice

“…[8][9][10][11][12] Recently research shows that the KRS failed to discriminate between high-and low-risk patients with cancer for VTE development, including patients with lymphoma. [13][14][15][16]36,37 This is further supported by our study in which the KRS did not adequately predict VTE events in patients at a higher risk of VTE in a cohort of patients with lymphoid malignancies. 37 Therefore, Antic et al developed the prognostic Thrombosis Lymphoma (ThroLy) score which is more specific for lymphoma patients than any other available scores targeting thrombosis in cancer patients.…”

“…Due to poor discriminatory performance, most of the recently established VTE-assessment models have proven to be of limited clinical utility because of the low predictive value of VTE events in subsequent studies, particularly in studies based on a single cancer cohort. [13][14][15][16] It is believed that the risk to patients with lymphoma, undergoing ambulatory chemotherapy, of developing VTE is similar to that of patients with solid tumours with the incidence reaching 14.6%. 17,18 Lymphoma is considered to constitute a high risk of VTE development in the best-validated model to stratify outpatients with cancer, which was developed by Khorana and is known as the Khorana risk score (KRS).…”

Development and Validation of a Risk Score for Prediction of Venous Thromboembolism in Patients With Lung Cancer

“…16 Our center has built the practice of prevention strategy for bedridden patient due to its well-recognized correlation with VTE. The parameter of hemogram (hemoglobin, platelets, and leukocyte) that was used in the other studies [18][19][20] was not included in our system because few cases above normal level were observed in our data set. Finally, the variables of the possible risk factors included in this study are different from the previous predictive models.…”

Risk factors for cancer‐associated venous thromboembolism: The venous thromboembolism prevention in the ambulatory cancer clinic (VTE‐PACC) study

“…4 Many professional organizations and researchers have concerns about whether these scores are accurate enough to make recommendations on prescribing VTE prophylaxis. [5][6][7] The Khorana Score was developed using data from an observational study of outpatient cancer patients initiating chemotherapy, and stratifies these patients into high, intermediate, and low risk of developing VTE during the subsequent 6 months. 8 This score includes tumor type, body mass index (BMI), and pre-chemotherapy hemoglobin, white blood cell, and platelet counts.…”

“…To that end scoring systems are available to predict VTE risk in individuals with cancer . Many professional organizations and researchers have concerns about whether these scores are accurate enough to make recommendations on prescribing VTE prophylaxis …”