[Renovascular safety of bevacizumab in breast cancer patients. The prognostic value of hypertension and proteinuria]

The mechanism and treatment of targeted anti-tumour drugs induced cardiotoxicity

As the intensive anti-tumour therapy and combination of multiple anti-tumour drugs, cardiotoxicity events caused by anti-tumour drugs have also increased significantly, and the incidence of cardiotoxicity also increased with survival time. Different types of anti-tumour drugs could cause all kinds of cardiotoxicity which increase the difficulties in treatment and even live threatening. In this review, we concentrated in the targeted anti-tumour drugs such as human epidermal growth factor receptor-2 (HER2) inhibitors, tyrosine kinase inhibitors (TKIs), immune checkpoint inhibitors (ICIs), and proteasome inhibitors (Pls). The molecular mechanism of how these drugs induce cardiotoxicity is introduced which includes several signal pathways. These drugs induced cardiotoxicity involved heart failure, hypertension, atherosis and thrombosis, QT interval prolongation, and myocarditis. Some of the cardiotoxicity could be moderate and reversible but others could have happened severely.The aim of this review is to summarise the targeted anti-tumour drugs induced cardiotoxicity and treatment strategies.

[Angiogenesis inhibitors: mechanism of action and nephrotoxicity]

Tumoral angiogenesis is a key mechanism involved in the growth and spread of cancer cells. The development of angiogenesis inhibitors, particularly those targeting the Vascular Endothelial Growth Factor (VEGF) pathway, has improved the prognosis and survival of many cancer patients since they were approved in 2005 in France. Vascular Endothelial Growth Factor inhibitors have different mechanisms of action, targeting either the ligand (e.g. bevacizumab, anti-Vascular Endothelial Growth Factor monoclonal antibody; aflibercept, recombinant anti-Vascular Endothelial Growth Factor fusion protein), or its receptors such as tyrosine kinase inhibitors (e.g. sunitinib or sorafenib). These treatments can be combined with conventional chemotherapy, or other anti-cancer therapies, and are associated with variable tolerance depending on the patient's clinical condition and comorbidities. Additionally, angiogenesis inhibition may be associated with cardiovascular and/or kidney toxicity and therefore special monitoring is needed during the treatment duration. Development of hypertension and proteinuria are the commonest renal side effects; these are generally manageable and reversible when treatment is stopped. However, more severe toxicities have been reported such as acute kidney injury, glomerular and/or vascular insults such as thrombotic microangiopathy, and more rarely tubulointerstitial damage. The prescribing physician should be aware of these potentially serious. This article describes the mechanisms of action of antiangiogenic agents and their potential toxicities, with particular respect to the kidneys.

Increased risk of adverse drug events secondary to bevacizumab treatment in patients with advanced or metastatic breast cancer: a meta-analysis of randomized controlled trials

Background

Several clinical trials have shown an increased risk of hypertension with bevacizumab when added to chemotherapy in different types of malignancy; however, the risks of other significant adverse events besides hypertension, specifically in breast cancer, have not been completely elucidated. This study was conducted with the aim, primarily, to assess the overall incidence and risk of common toxicities associated with bevacizumab in patients with advanced or metastatic breast cancer and, secondarily, to descriptively review study results concerning a potential correlation between bevacizumab-induced hypertension and its efficacy for breast cancer treatment.

Methods

We carried out a meta-analysis of relevant randomized controlled trials (RCTs) identified from a database search (Cochrane Library and PubMed) and, additionally, by reviewing previous reviews and meta-analyses. Overall incidence rates, odds ratios (ORs), and 95% confidence intervals (CIs) were assessed with the random- or fixed-effect models, depending on the level of heterogeneity across the included trials. The primary clinical outcomes were high-grade adverse events commonly reported with bevacizumab therapy.

Results

We included 6,260 patients with advanced-stage breast cancer from 12 RCTs in the meta-analysis. Five types of high-grade (Grade 3 or 4) adverse drug events were identified as being correlated with bevacizumab treatment versus alternative treatment with statistical significance: hypertension (OR 5.67, 95% CI 3.02–10.65), proteinuria (OR 10.09, 95% CI 4.79–21.27), bleeding (OR 3.45, 95% CI 2.25–5.30), cardiac toxicity (OR 2.15, 95% CI 1.29–3.59), and neutropenic fever (OR 1.51, 95% CI 1.15–2.00). The prognostic value of bevacizumab-induced hypertension for its antitumor efficacy among patients with breast cancer remains controversial, with mixed results presented in the five retrospective studies that were identified from our additional literature search.

Conclusion

The addition of bevacizumab to anticancer therapy was associated with a significant increase in the risk of high-grade adverse events, including hypertension, proteinuria, bleeding, cardiac toxicity, and neutropenic fever among patients with advanced-stage breast cancer. Although several retrospective studies suggested a predictive importance of hypertension secondary to bevacizumab therapy, the role of elevated blood pressure as a prognostic biomarker for its antitumor efficacy remains controversial, and further prospective trials are required to confirm such a correlation.