Models for predicting venous thromboembolism in ambulatory patients with lung cancer: a systematic review protocol

Models for predicting venous thromboembolism in ambulatory patients with lung cancer: A systematic review and meta-analysis

AIMS

The incidence of venous thromboembolism (VTE) in patients with lung cancer is relatively high, and risk stratification models are vital for the targeted application of thromboprophylaxis. We aimed to review VTE risk prediction models that have been developed in patients with lung cancer and evaluated their performance.

METHODS AND RESULTS

Twenty-four eligible studies involving 123,493 patients were included. The pooled incidence of VTE within 12 months was 11 % (95 % CI 8 %-14 %). With the identified four VTE risk assessment tools, meta-analyses did not show a significant discriminatory capability of stratifying VTE risk for Khorana, PROTECHT and CONKO scores. The pooled sensitivity and specificity of the Khorana score were 24 % (95 % CI 11 %-44 %) and 84 % (95 % CI 73 %-91 %) at the 3-point cut-off, and 43 % (95 % CI 35 %-52 %) and 61 % (95 % CI 52 %-69 %) at the 2-point cut-off. However, a COMPASS-CAT score of ≥ 7 points indicated a significantly high VTE risk, with a RR of 4.68 (95 % CI 1.05-20.80).

CONCLUSIONS

The Khorana score lacked discriminatory capability in identifying patients with lung cancer at high VTE risk, regardless of the cut-off value. The COMPASS-CAT score had better performance, but further validation is needed. The results indicate the need for robust VTE risk assessment tools specifically designed and validated for lung cancer patients. Future research should include relevant biomarkers as important predictors and consider the combined use of risk tools. PROSPERO registration number: CRD42021245907.

Novel Insights in Venous Thromboembolism Risk Assessment Methods in Ambulatory Cancer Patients: From the Guidelines to Clinical Practice

Many cancer patients will experience venous thromboembolism (VTE) at some stage, with the highest rate in the initial period following diagnosis. Novel cancer therapies may further enhance the risk. VTE in a cancer setting is associated with poor prognostic, a decreased quality of life, and high healthcare costs. If thromboprophylaxis in hospitalized cancer patients and perioperative settings is widely accepted in clinical practice and supported by the guidelines, it is not the same situation in ambulatory cancer patient settings. The guidelines do not recommend primary thromboprophylaxis, except in high-risk cases. However, nowadays, risk stratification is still challenging, although many tools have been developed. The Khrorana score remains the most used method, but it has many limits. This narrative review aims to present the current relevant knowledge of VTE risk assessment in ambulatory cancer patients, starting from the guideline recommendations and continuing with the specific risk assessment methods and machine learning models approaches. Biomarkers, genetic, and clinical features were tested alone or in groups. Old and new models used in VTE risk assessment are exposed, underlining their clinical utility. Imaging and biomolecular approaches to VTE screening of outpatients with cancer are also presented, which could help clinical decisions.

Incidence of venous thromboembolism and discriminating capacity of Khorana score in lung cancer patients treated with immune checkpoint inhibitors

Venous-thromboembolism (VTE) is increased in lung cancer patients (LCP) treated with immune-checkpoint inhibitors (ICIs) but risk factors are not identified and the Khorana Score (KS) is not validated. To assess VTE incidence and its clinical impact, to investigate potential clinical risk factors and KS performance in LCP. Retrospective analysis of LCP initiating ICIs treatment between June 2015 and November 2020 in a for-profit cancer center. 481 patients were included: 62% adenocarcinoma, 70% PDL1 + , 86% stage-IV-disease. Over a median follow-up of 9.8 months, 47 VTE were observed: 28 pulmonary embolisms, 15 deep venous thromboses (distal n = 9, proximal n = 6), 3 inferior vena cava thromboses, 1 other VTE, no superficial or digestive vein thrombosis. Median time from ICIs' initiation to VTE was 180 (11-1277) days. Overall survival was significantly lower in patients who experienced VTE (42.5 vs. 86.8 months, p = 0.006). In univariate analysis patients VTE was more frequent in metastatic patients (11.1% vs. 1.5%, p = 0.015) and lower in those treated with durvalumab (1.9% vs. 9.6%, p = 0.046). Logistic regression analysis showed that non-metastatic status (OR 0.13; 0.02-0.95, p = 0.04) and BMI (OR 1.07; 1.01-1.14, p = 0.028) were associated with VTE. The rate of VTE was the same in patients with a KS < or ≥ 2 (10.2% vs. 9.3%, p = 0.87). ICIs-treated LCP are at high risk of thromboembolism. VTE has a negative impact on survival. KS does not perform well in LCP. It is important to identify which VTE prediction models are available to be used in adult ambulatory lung cancer patients.