Development of a Clinical Prediction Rule for Risk Stratification of Recurrent Venous Thromboembolism in Patients With Cancer-Associated Venous Thromboembolism

Abstract

Background-Long-term low-molecular-weight heparin (LMWH) is the current standard for treatment of venous thromboembolism (VTE) in cancer patients. Whether treatment strategies should vary according to individual risk of VTE recurrence remains unknown. We performed a retrospective cohort study and a validation study in patients with cancer-associated VTE to derive a clinical prediction rule that stratifies VTE recurrence risk. Methods and Results-The cohort study of 543 patients determined the model with the best classification performance included 4 independent predictors (sex, primary tumor site, stage, and prior VTE) with 100% sensitivity, a wide separation of recurrence rates, 98.1% negative predictive value, and a negative likelihood ratio of 0.16. In this model, the score sum ranged between Ϫ3 and 3 score points. Patients with a score Յ0 had low risk (Յ4.5%) for recurrence and patients with a score Ͼ1 had a high risk (Ն19%) for VTE recurrence. Subsequently, we applied and validated the rule in an independent set of 819 patients from 2 randomized, controlled trials comparing low-molecular-weight heparin to coumarin treatment in cancer patients. Conclusions-By identifying VTE recurrence risk in cancer patients with VTE, we may be able to tailor treatment, improving clinical outcomes while minimizing costs. (Circulation. 2012;126:448-454.)

Epidemiology of cancer-associated venous thrombosis

“…46,69 A clinical prediction rule (Ottawa prognostic score) has been developed for recurrent venous thrombosis during the first 6 months of anticoagulant treatment in a retrospective cohort study of 543 patients with a cancer-associated venous thrombotic event. 70 The final model included 4 predictors (gender, primary tumor site, stage, and number of prior venous thrombotic events) leading to a score sum that ranged between 23 and 13 points. Patients with a score <0 had a low risk of recurrence (4%), whereas patients with a score >1 had a relatively high recurrence risk (16%).…”

Cancer‐associated thrombosis: The search for the holy grail continues

“…Over the years, several risk assessment tools have been developed to estimate the risk of CAT,6, 10, 11, 12 but unfortunately, the accuracy of such tools is very low 9, 13, 14. The main limitations of these risk assessment tools are: (a) while performing better in large cohort studies these tools are unable to predict CAT at the individual level, (b) these models are not developed for specific cancer types, (c) they underperform when used to predict risk of recurrence VTE, and (iv) they poorly predict increased risk of mortality.…”

Pulmonary embolism: clinical guidelines of European Society of Cardiology (2014)*

“…Среди пациентов с ВТЭ (n > 35 000) рак был наиболее сильным самостоятельным фактором риска как для общей летальности, так и для леталь ности, связанной с ТЭЛА [20]. Самый неблагоприят ный прогноз обусловлен повышением риска крово течений на фоне АКТ и высокой частотой рецидивов ВТЭ [450][451][452][453][454].…”

“…Риск рецидивов ТЭЛА при онкологических забо леваниях недавно оценивался в когортном исследо вании (n = 543) и затем валидизирован как самосто ятельный признак (n = 819) [453]. Предложенная шкала прогнозирования риска рецидивов включала рак молочной железы (-1 балл), метастазы в лимфа тические узлы I или II стадии (-1 балл), женский пол, рак легкого и предшествующие ВТЭ (+1 балл за каждый признак).…”

“…Предложенная шкала прогнозирования риска рецидивов включала рак молочной железы (-1 балл), метастазы в лимфа тические узлы I или II стадии (-1 балл), женский пол, рак легкого и предшествующие ВТЭ (+1 балл за каждый признак). В случае если показатель со ставлял ≤ 0 баллов, отмечался низкий риск (≤ 4,5 %) рецидивов ВТЭ, > 1 балла -оценивался как высокий риск (≥ 19 %) [453]. Эта шкала помогает принимать индивидуализированное решение о длительности АКТ.…”