Venous and arterial thromboembolic events with immune checkpoint inhibitors: A systematic review

Immune checkpoint inhibitor treatment and atherosclerotic cardiovascular disease: an emerging clinical problem

Antibody-mediated blockade of co-inhibitory molecules such as cytotoxic T lymphocyte-associated protein 4, PD1 and PDL1 elicits potent antitumor responses and improves the prognosis of many patients with cancer. As these immune checkpoint inhibitors (ICIs) are increasingly prescribed to a diverse patient population, a broad range of adverse effects is emerging. Atherosclerosis, a lipid-driven chronic inflammatory disease of the large arteries, may be aggravated by ICI treatment. In this review, we discuss recent clinical studies that analyze the correlation between ICI use and atherosclerotic cardiovascular disease (CVD). Indeed, several studies report an increased incidence of atherosclerotic CVD after ICI administration, with the occurrence of pathologies such as myocardial infarction, ischemic stroke and coronary artery disease significantly higher after ICI use. Increased awareness and better monitoring of ICI-treated patients can elucidate risk factors that contribute to ICI-induced aggravation of atherosclerosis and identify promising treatment strategies. For now, optimal cardiovascular risk assessment is required to protect ICI-receiving patients and long-term survivors of cancer from the detrimental effects of ICI therapy on atherosclerotic CVD.

Immune Checkpoint Inhibitors and Atherosclerotic Vascular Events in Cancer Patients

In clinical trials and meta-analysis, atherosclerotic vascular events (AVEs) during treatment with immune-checkpoint inhibitors (ICIs) have been reported with low incidence. However, preclinical data suggest that these drugs can promote atherosclerosis inflammation and progression of atherosclerosis plaques, and there is now growing and convincing evidence from retrospective studies that ICIs increase the risk of atherosclerotic vascular events including arterial thrombosis, myocardial infarction and ischemic stroke. Prospective studies are needed to increase knowledge on long-term effect of ICIs or their combinations with other cardio-toxic drugs, but in the meantime a careful assessment and optimization of cardiovascular risk factors among patients treated with ICIs is advisable.

Prognostic impact and risk factors of cancer-associated thrombosis events in stage-IV cancer patients treated with immune checkpoint inhibitors

BACKGROUND

Cancer-associated thrombosis (CAT) is a major cause of mortality in cancer patients. Immune checkpoint inhibitors (ICIs) have been associated with multiple side effects including CAT. The aim of this study is to investigate risk factors and prognostic impact associated with CAT events during ICIs treatment.

METHODS

This is a multi-center retrospective study that included stage IV cancer patients treated with ICIs.

RESULTS

We identified 552 cancer patients treated with ICIs. During follow-up time, 58 (10.5%) patients developed 67 venous thromboembolism (VTE) events while on ICIs. Anticoagulation use at the time of ICIs treatment start was associated with significantly higher VTE incidence rate (IRR: 2.23). No significant difference in VTE IRR was observed depending on response to ICIs treatment, aspirin use, or Khorana VTE risk score. Melanoma as primary cancer, Khorana score, ECOG status, and anemia at baseline were able to predict mortality.

CONCLUSIONS

The incidence of CAT in stage-IV cancer patients treated with ICIs was higher in our study compared to previous reports. Control group of patients who did not receive ICIs is needed for better identification of CAT risk factors. Khorana score was a good predictor of mortality but not CAT risk and needs to be further validated in a homogenous group of patients.

Cancer Therapy-Associated Thrombosis

[Figure: see text].