Clinical models and biochemical predictors of VTE in lung cancer

Stratification of Risk Factors of Lung Cancer-Associated Venous Thromboembolism and Determining the Critical Point for Preemptive Intervention: A Systematic Review With Meta-analysis

Background

Several biomarkers or risk factors have been identified and several prediction models exist. The major limitations inherent in these models include cost-ineffectiveness and lack of systematic stratification of risk factors resulting in the inclusion of clinically insignificant biomarkers in the models. This review aimed to systematically stratify the risk factors of lung cancer-associated venous thromboembolism (VTE) and determine the critical point for preemptive intervention.

Methods

This systematic review was structured as per the Preferred Reporting Item for Systematic Reviews and Meta-analyses. We searched MEDLINE, PubMed, Cochrane Library, CINAHL, Academic Search Complete, and PsycINFO from the onset to June 2022. We included studies that reported the risk factors of lung cancer-associated VTE and corresponding risk estimates, irrespective of treatment status but studies were excluded if patients were on anti-VTE medications. We employed random effects models of meta-analysis and computed risk stability index and risk weight (Rw) to achieve the review objectives. The review protocol is registered with PROSPERO (CRD42022336476).

Results

The clinically significant risk factors of VTE in lung cancer patients were D-dimer (odds ratio [OR] = 5.510, 95% CI = 2.6-11.7; Rw = 5.0), albumin (OR = 2.2, 95% CI = 1.0-4.8; Rw = 1.79), leukocyte (OR = 2.48, 95% CI = 1.9-3.2; Rw = 1.77), histological type (OR = 1.69 , 95% CI = 1.2-2.4; Rw = 1.3), age (OR = 1.56; Rw = 0.99), and hemoglobin (OR = 1.85, 95% CI = 1.3-2.6; Rw = 0.92). Based on the distribution of Rw across risk factors, the critical point (upper third of the upper quartile class) was 4.5 and may mark the point at which preemptive intervention should be commenced.

Conclusions

Targeted screening for VTE in lung cancer patients could be patient-specific and should be based on a combination of the most significant risk factors required to meet the critical point, provided that such a combination is affordable as illustrated in the ALBAH model.

Registration

The review protocol is registered with PROSPERO (ID: CRD42022336476).

Could PD-L1 positivity be associated with venous thrombosis in patients with non-small cell lung cancer?

The risk of venous thromboembolism (VTE) is increased in non-small cell lung cancer (NSCLC), and defining at-risk patients is important. Thus, we aimed to assess the association between programmed cell death ligand 1 (PD-L1) expression and VTE [pulmonary embolism (PE), deep venous thrombosis (DVT)] in NSCLC. In this retrospective, observational multicentre study, 369 patients with NSCLC who had PD-L1 immunohistochemistry based on biopsies taken between January 2017 and December 2019, were divided as PD-L1-positive (n = 181) and -negative (n = 188) groups, and low-positive (n = 99) and high-positive (n = 82) PD-L1 groups. Among all population, 12.5% of them developed a VTE during a median follow-up of 474 days. The rates of DVT, PE, and PE + DVT were 5.7%, 6% and 0.8%, respectively. VTE (15.5% vs. 9.5%) and DVT (3.8% vs. 7.4%) were similar between two groups, while PE was significantly higher in PD‑L1-positive group than those in PD-L1-negative group (11.1% vs 1%, p < 0.001). There were no significant differences between low- and high-positive groups in terms of VTE (14.1% vs. 17%), PE (12.1% vs. 9.8%), and DVT (2% vs. 6.1%). In the multivariate analysis, multiple metastases (Hazard ratio [HR] 4.02; 95% confidence interval [Cl] 1.18-13.63; p = 0.07) and PD-L1 positivity was associated with an increased PE risk (HR 8.39; 95% Cl 2.07-34.07; p = 0.003). In conclusion, PD-L1 positivity may be of important role in predicting the increased risk of PE in patients with NSCLC and thereby may be used to define patients likely to benefit from thromboprophylaxis.

Advances in the Prediction and Risk Assessment of Lung Cancer-Associated Venous Thromboembolism

According to the most recent data from the National Cancer Center, venous thromboembolism (VTE) has unsurprisingly become one of the most common complications in lung cancer. VTE not only interferes with the equilibrium of the clotting system but it also affects tumor progression and prognosis. For the identification of high-risk patients, many clinical risk assessment models have been developed and validated based on the risk factors found in previous studies. In this review, we will summarize advances in prediction and risk assessment of VTE, with a focus on early diagnosis and therapy, reduction of mortality, and the burden of medical costs in lung cancer patients.

Risk Factors and Prediction Models for Venous Thromboembolism in Ambulatory Patients with Lung Cancer

Venous thromboembolism (VTE) is a significant cause of mortality in patients with lung cancer. Despite the availability of a wide range of anticoagulants to help prevent thrombosis, thromboprophylaxis in ambulatory patients is a challenge due to its associated risk of haemorrhage. As a result, anticoagulation is only recommended in patients with a relatively high risk of VTE. Efforts have been made to develop predictive models for VTE risk assessment in cancer patients, but the availability of a reliable predictive model for ambulate patients with lung cancer is unclear. We have analysed the latest information on this topic, with a focus on the lung cancer-related risk factors for VTE, and risk prediction models developed and validated in this group of patients. The existing risk models, such as the Khorana score, the PROTECHT score and the CONKO score, have shown poor performance in external validations, failing to identify many high-risk individuals. Some of the newly developed and updated models may be promising, but their further validation is needed.

High plasma levels of soluble P-Selectin and Factor VIII predict venous thromboembolism in non-small cell lung cancer patients: The Thrombo-Nsclc risk score

INTRODUCTION

Venous thromboembolism (VTE) is common in non-small cell lung cancer (NSCLC) patients undergoing systemic chemotherapy. The usefulness of Khorana score (KRS) to predict risk in lung cancer patients is limited, and the identification of patients who would benefit most from thromboprophylaxis is challenging. We aimed to identify variables whose values before chemotherapy helped in predicting VTE occurrence, and build a model to assess VTE risk.

MATERIALS AND METHODS

A cohort of newly diagnosed NSCLC patients to undergo outpatient chemotherapy, not under anticoagulant treatment, was recruited. Pre-chemotherapy demographic, clinical, analytical and tumor-specific variables were collected. Patients were prospectively followed-up for 12 months to record VTE events. Bivariate and multivariate analyses were performed to identify VTE-associated variables, and a prediction model was built and compared with KRS.

RESULTS

90 patients were recruited, 18 of whom had a VTE event during follow-up. High baseline levels of factor VIII (FVIII) and, especially, soluble P-selectin (sP-selectin), were independently associated with VTE risk (hazard ratio [HR] 4.15, 95% confidence interval [CI] 1.17-14.71, and 66.40 [8.70-506.69], respectively). Our so-called Thrombo-NSCLC risk score, which assigns 1 and 3 points to high FVIII and sP-selectin values, respectively, was significantly better than KRS in predicting VTE (area under the curve [AUC] 0.93 vs. 0.55, sensitivity 94.4 vs. 35.0%, specificity 93.1 vs. 60.0%). Our prediction model showed significant discriminating capacity between high risk vs. intermediate/low risk patients, while KRS did not.

CONCLUSIONS

The Thrombo-NSCLC risk score may be useful to identify those NSCLC patients who would benefit most from thromboprophylaxis.

Cerebral Thromboembolism after Lobectomy for Lung Cancer: Pathological Diagnosis and Mechanism of Thrombus Formation

Lung cancer is the leading cause of cancer-related deaths worldwide. Although molecular therapies have emerged as efficacious strategies for the treatment of lung cancer, surgical resection is still recommended as a radical therapeutic option. Currently, lobectomy is regarded as the most reliable radical treatment of primary lung cancer. Among the various complications after lobectomy, cerebral thromboembolism requires attention as a life-threatening complication during the early postoperative period. It occurs in 0.2–1.2% of surgical cases of lung cancer and typically develops following left upper lobectomy with a long pulmonary vein stump (PVS). PVS-associated thrombosis is known to cause cerebral thromboembolism after such procedures; however, distinguishing this specific complication from that caused by postoperative atrial fibrillation is challenging. We summarize herein the diagnostic pathology of thrombus formation in accordance with its thrombogenic mechanism. We focus on the potential utility of the pathological assessment of thrombectomy specimens. The morphological information obtained from these specimens enables the presumption of thrombogenic etiology and provides useful clues to both select an appropriate pharmacotherapy and determine a follow-up treatment for cerebral thromboembolism.

Predicting VTE in Cancer Patients: Candidate Biomarkers and Risk Assessment Models

Risk prediction of chemotherapy-associated venous thromboembolism (VTE) is a compelling challenge in contemporary oncology, as VTE may result in treatment delays, impaired quality of life, and increased mortality. Current guidelines do not recommend thromboprophylaxis for primary prevention, but assessment of the patient's individual risk of VTE prior to chemotherapy is generally advocated. In recent years, efforts have been devoted to building accurate predictive tools for VTE risk assessment in cancer patients. This review focuses on candidate biomarkers and prediction models currently under investigation, considering their advantages and disadvantages, and discussing their diagnostic performance and potential pitfalls.

Epidemiology and risk factors for venous thromboembolism in lung cancer

PURPOSE OF REVIEW

Cancer is a strong risk factor for venous thromboembolism (VTE). In patients with lung cancer VTE is a significant cause for morbidity and mortality. The purpose of the review is to summarize the epidemiology of thrombotic events, risk factors for VTE and the clinical impact of VTE in patients with lung cancer.

RECENT FINDINGS

The rates of VTE in lung cancer patients vary according to different types of investigations, and reach 7 to 13%, including a significant number of unsuspected pulmonary emboli. Risk factors for VTE in patients with lung cancer can be basically divided into three categories: patient, tumor, and treatment related. In addition, a number of biomarkers have been described to be associated with VTE risk (e.g., D-dimer).

SUMMARY

Knowledge about the epidemiology, risk factors, and prognostic value of VTE in lung cancer could help to prevent thrombotic complications and improve management of patients with lung cancer.

Impact of VEGF gene polymorphisms in elderly cancer patients: clinical outcome and toxicity

Vascular endothelial growth factors (VEGFs) are the key regulators in angiogenesis and have been shown to play a significant role in the progression and prognosis of angiogenesis-related diseases, such as cancer. VEGF inhibitors are a current pharmacological tumoral strategy. However, despite the strong association between aging and cancer incidence and progression, recent findings suggest impaired angiogenesis accompanied by a reduced expression of VEGF in cells derived from aging subjects. Specific variations of VEGF genes have been demonstrated to be genetic determinants for susceptibility, outcome and therapy response, especially for the solid tumors. Considering the complications present in frail elderly patients, analysis of VEGF genetic polymorphisms in these subjects may further help in tailoring an angiogenic pharmacological strategy, and in improving our ability to better understand prognosis during therapy-related to cancer.

VEGF gene promoter polymorphisms and risk of VTE in chemotherapy-treated cancer patients

Among the possible genetic contributors to cancer-related venous thromboembolism (VTE), vascular endothelial growth factor (VEGFA) could play an important role, as an imbalance of the VEGFA system (either disease-related or drug-induced) may result in a disturbance of vascular homeostasis. Thus, this study was designed to investigate the predictive role of eight different VEGFA gene promoter single nucleotide polymorphisms (SNPs) for a first VTE episode in cancer out-patients undergoing chemotherapy. To this purpose, VEGFA gene promoter polymorphisms were analysed in 297 cancer patients using polymerase chain reaction amplification and direct DNA sequencing analysis. One hundred forty unrelated healthy subjects from the same geographical area were also analysed in order to evaluate and compare genotype/haplotype frequencies in our ethnicity. VTE occurred in 26 (9%) of cancer patients with a median time-to-event of 3.4 months. Association analyses showed that -1154G/A polymorphism was significantly associated with the risk of chemotherapy-triggered VTE, with the A allele exerting a protective role both in the overall population (hazard ratio [HR]: 0.21; 95% confidence interval [CI]: 0.07-0.58) or in bevacizumab-treated metastatic patients (HR: 0.09, 95%CI: 0.01-0.86) in whom VEGFA -1154AA genotype also conferred a reduced risk of early progression (HR: 0.58, 95%CI: 0.34-0.98). These results suggest that VEGFA may represent a candidate gene contributing to VTE development in chemotherapy treated cancer patients and that -1154G/A SNP might provide useful clinical information on the efficacy and toxicity of bevacizumab in metastatic patients. Validation studies are needed for translation into clinical practice.

Predictive value of HDL cholesterol for cancer-associated venous thromboembolism during chemotherapy

BACKGROUND

Dyslipidemia is a well-known risk factor for the development of atherothrombosis; however, its involvement in venous thromboembolism (VTE) is still debated. Low levels of HDL cholesterol (HDL-C) have been found to be associated with VTE, which is a common complication of cancer and its treatment. VTE incidence is increased in cancer patients, especially those undergoing chemotherapy.

OBJECTIVE

We sought to investigate the value of pretreatment HDL-C in the risk prediction of future VTE in a population of ambulatory cancer patients undergoing chemotherapy.

PATIENTS AND METHODS

Blood lipid composition was retrospectively evaluated in 592 consecutive patients with primary (n = 373) or relapsing/recurrent (n = 219) solid cancers at the start of a new chemotherapy regimen (12% neoadjuvant, 31% adjuvant, 57% metastatic).

RESULTS

VTE occurred during chemotherapy in 38 patients (median time-to-event: 3 months). Mean HDL-C levels were lower in patients who developed VTE during chemotherapy (41 mg dL(-1) ; standard deviation [SD] 13 mg dL(-1) ) than in those who did not (48 mg dL(-1) ; SD 14 mg dL(-1) ). Cox proportional hazard survival analysis showed that HDL-C levels ≤ 43 mg dL(-1) were able to significantly predict a first VTE episode, with a hazard ratio of 2.87 (95% confidence interval 1.45-5.68). Moreover, patients with HDL-C levels ≤ 43 mg dL(-1) had worse 1-year VTE-free survival (86%) than those with HDL-C levels > 43 mg dL(-1) (96%; log rank test, 3.14).

CONCLUSIONS

Patients with low HDL-C levels have a three-fold higher risk of developing a first VTE episode during chemotherapy. Baseline analysis of HDL-C levels might be of clinical value in predicting VTE in cancer outpatients treated with anticancer drugs.