Development and validation of multivariable predictive model for thromboembolic events in lymphoma patients

Abstract

Lymphoma patients are at increased risk of thromboembolic events but thromboprophylaxis in these patients is largely underused. We sought to develop and validate a simple model, based on individual clinical and laboratory patient characteristics that would designate lymphoma patients at risk for thromboembolic event. The study population included 1,820 lymphoma patients who were treated in the Lymphoma Departments at the Clinics of Hematology, Clinical Center of Serbia and Clinical Center Kragujevac. The model was developed using data from a derivation cohort (n = 1,236), and further assessed in the validation cohort (n = 584). Sixty-five patients (5.3%) in the derivation cohort and 34 (5.8%) patients in the validation cohort developed thromboembolic events. The variables independently associated with risk for thromboembolism were: previous venous and/or arterial events, mediastinal involvement, BMI>30 kg/m(2) , reduced mobility, extranodal localization, development of neutropenia and hemoglobin level < 100g/L. Based on the risk model score, the population was divided into the following risk categories: low (score 0-1), intermediate (score 2-3), and high (score >3). For patients classified at risk (intermediate and high-risk scores), the model produced negative predictive value of 98.5%, positive predictive value of 25.1%, sensitivity of 75.4%, and specificity of 87.5%. A high-risk score had positive predictive value of 65.2%. The diagnostic performance measures retained similar values in the validation cohort. Developed prognostic Thrombosis Lymphoma - ThroLy score is more specific for lymphoma patients than any other available score targeting thrombosis in cancer patients. Am. J. Hematol. 91:1014-1019, 2016. © 2016 Wiley Periodicals, Inc.

Risk factors for venous thromboembolism in patients with lymphoma requiring hospitalization

“…Patients as those with low-grade histology who did not require a hospital stay were not retrieved. As expected, this may explain the higher incidence rate of VTE with respect to other reports 1,2,8,10 . Therefore, our study tackles the issue of VTE frequency in a population at increased risk, in whom special care is required and specific information are needed.…”

“…Comparison with other studies 8,10 is difficult because of differences in patient selection. Our study cohort is a real-life case series including both HL and NHL, including also VTE that was present before the start of therapy.…”

“…The incidence of VTE during chemotherapy in NHL patients was investigated analyzing the databases of 12 Italian clinical trials, identifying DLBCL histology and Khorana score as risk factors 8 . A recent monocentric study identified mediastinal involvement, BMI > 30 kg/m 2 , reduced mobility, extranodal localization, development of neutropenia and hemoglobin level < 100 g/L as VTE risk factors in patients who had received at least one chemotherapy cycle 10 .…”

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

“…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) . Based on these data and some variables from the KRS, Antic et al developed and validated a multivariable model for thromboembolic events in lymphoma patients known as the Thrombosis Lymphoma (ThroLy) score . To this day, there have been no external validation studies to evaluate the ThroLy score in clinical practice …”

Can Biomarkers of Coagulation, Platelet Activation, and Inflammation Predict Venous Thromboembolism in Patients with Haematological Malignancies?

“…In 2018, an international study published in the Lancet developed a simple clinical prediction model incorporating only one clinical factor (tumour site category) and one biomarker (D-dimer) that could predict the risk of VTE in ambulatory patients with solid cancers [23]. Concerning haematological malignancies, some predictive models have been developed to identify patients at risk of VTE development, such as the ThroLy score, which was validated by Antic et al [24] in lymphoma patients with variables including previous venous and/or arterial events, mediastinal involvement, BMI > 30, reduced mobility, extranodal localization, development of neutropenia, and haemoglobin < 100 g/L. In newly diagnosed acute myeloid leukaemia (AML) patients, Libourel et al [25] showed that disseminated intravascular coagulation (DIC) markers at diagnosis are strong predictors for both arterial and venous thrombosis.…”