Safety of bevacizumab in treating metastatic colorectal cancer: a systematic review and meta-analysis of all randomized clinical trials

Boswellia Serrata for Cerebral Radiation Necrosis After Radiosurgery for Brain Metastases

PURPOSE

Radiation necrosis (RN) is a dose-limiting toxicity of stereotactic radiosurgery (SRS) for brain metastases. Oral corticosteroids are not optimal for long-term management, given multiple side effects. Boswellia serrata (BS) is an over-the-counter supplement traditionally known for its anti-inflammatory properties and has recently been shown to reduce cerebral edema. We evaluated the response rates of BS in a series of patients with RN after SRS for brain metastases.

METHODS AND MATERIALS

We identified patients who developed any grade RN after SRS and received BS for ≥2 months at a target dose of 4050 to 4500 mg daily. The primary endpoint was objective response rate (ORR), including complete response (CR) or partial response (PR), defined as ≥30% decrease in edema volume on T2-fluid-attenuated inversion recovery magnetic resonance imaging from baseline.

RESULTS

A total of 100 patients received BS, of which 94 patients with adequate follow-up were included. The median SRS dose was 24 Gy in 3 fractions, and 44%, 47%, and 9% of patients had grade 1, 2, and 3 RN, respectively. The best response was CR in 12% and PR in 48%, while 28% had stable edema and 12% had progression of edema. The overall ORR was 59.6% (95% CI, 48.9%-69.6%). ORR was 62%, 63%, and 33% for grade 1, 2, and 3 RN, respectively. The median duration of response in patients with CR or PR was 13.9 months (IQR, 9-23). Among 69 patients (73%) who never received steroids, received prior steroids only, or had a stable or decreasing steroid requirement of ≤4 mg per day of dexamethasone for at least >1 week prior to starting Boswellia, the ORR was 63.8%. Fourteen percent of patients had National Cancer Institute Common Terminology Criteria for Adverse Events grade 1, and 2% had grade 2 gastrointestinal toxicity. A total of 67% of patients remained on BS at the last follow-up.

CONCLUSIONS

Our study suggests that BS is a safe and feasible treatment option for grade 1 to 3 RN after SRS. Further prospective studies comparing BS with a placebo are warranted.

Gastrointestinal Malignancy: Genetic Implications to Clinical Applications

Advances in molecular genetics have revolutionized our understanding of the pathogenesis, progression, and therapeutic options for treating gastrointestinal (GI) cancers. This chapter provides a comprehensive overview of the molecular landscape of GI cancers, focusing on key genetic alterations implicated in tumorigenesis across various anatomical sites including GIST, colon and rectum, and pancreas. Emphasis is placed on critical oncogenic pathways, such as mutations in tumor suppressor genes, oncogenes, chromosomal instability, microsatellite instability, and epigenetic modifications. The role of molecular biomarkers in predicting prognosis, guiding treatment decisions, and monitoring therapeutic response is discussed, highlighting the integration of genomic profiling into clinical practice. Finally, we address the evolving landscape of precision oncology in GI cancers, considering targeted therapies and immunotherapies.

Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.

The anti-adhesive effect of anti-VEGF agents in experimental models: A systematic review

Adhesions constitute a major problem in abdominal-pelvic and thoracic surgery with significant impact in the postoperative quality of life and healthcare services utilization. Adhesiogenesis is the result of increased fibrin formation, impaired fibrinolysis, angiogenesis, and fibrosis. Despite the recent advancements, the ideal anti-adhesive agent remains to be determined. To this end, we performed a comprehensive literature search in PubMed, EMBASE, and Scopus databases to identify studies investigating the antiadhesive role of anti-VEGF agents in peritoneal, pleural, and pericardial experimental adhesion models. Fifteen studies were eligible for inclusion with a total population of 602 animals (334 rats, 180 rabbits, and 88 mice). The majority of included studies (11/15) used bevacizumab, while three studies used other anti-VEGF antibodies and one study used an anti-VEGFR-antibody. A rat model was used in nine studies, while rabbit (n = 3) or mouse (n = 3) models were used less frequently. Eleven studies used peritoneal models, three studies used pleural models, and one study used a pericardial model. The scales (n = 12) and interval (Range: 1-42 days) used for the evaluation of adhesions varied between the studies. All studies demonstrated a significant decrease in adhesion scores between the anti-VEGF and control groups up to 42 days postprocedure. VEGF blockade resulted in decreased fibrosis in four out of five studies that used peritoneal models, while the effect on pleural models depended on the pleurodesis agent and was significant between 7 and 28 days. The effect of anti-VEGF agents on anastomosis integrity depends on the dose and the model that is used (inconclusive results).Current data support the anti-adhesive role of Anti-VEGF agents in all three serosal surfaces up to 6 weeks postprocedure. Further studies are needed to confirm the anti-adhesive role of anti-VEGF agents in pleural and pericardial adhesion experimental models and investigate any effect on anastomosis integrity in peritoneal models.

Cardiovascular Toxicity of Targeted Therapies for Cancer: An Overview of Systematic Reviews

Background

Several targeted therapies for cancer have been associated with cardiovascular toxicity. The evidence for this association has not been synthesized systematically nor has the quality of evidence been considered. We synthesized systematic review evidence of cardiovascular toxicity of individual targeted agents.

Methods

We searched MEDLINE, Embase, and the Cochrane Database of Systematic Reviews for systematic reviews with meta-analyses of cardiovascular outcomes for individual agents published to May 2020. We selected reviews according to prespecified eligibility criteria (International Prospective Register of Systematic Reviews CRD42017080014). We classified evidence of cardiovascular toxicity as sufficient, probable, possible, or indeterminate for specific cardiovascular outcomes based on statistical significance, study quality, and size.

Results

From 113 systematic reviews, we found at least probable systematic review evidence of cardiovascular toxicity for 18 agents, including high- and all-grade hypertension for bevacizumab, ramucirumab, axitinib, cediranib, pazopanib, sorafenib, sunitinib, vandetanib, aflibercept, abiraterone, and enzalutamide, and all-grade hypertension for nintedanib; high- and all-grade arterial thromboembolism (includes cardiac and/or cerebral events) for bevacizumab and abiraterone, high-grade arterial thromboembolism for trastuzumab, and all-grade arterial thromboembolism for sorafenib and tamoxifen; high- and all-grade venous thromboembolism (VTE) for lenalidomide and thalidomide, high-grade VTE for cetuximab and panitumumab, and all-grade VTE for bevacizumab; high- and all-grade left ventricular ejection fraction decline or congestive heart failure for bevacizumab and trastuzumab, and all-grade left ventricular ejection fraction decline/congestive heart failure for pazopanib and sunitinib; and all-grade corrected QT interval prolongation for vandetanib.

Conclusions

Our review provides an accessible summary of the cardiovascular toxicity of targeted therapy to assist clinicians and patients when managing cardiovascular health.

Antiangiogenic Therapy in Colorectal Cancer

Colorectal carcinoma is the third most common cancer worldwide. Approximately 20% of patients with colorectal cancer will have metastatic disease at the time of initial diagnosis, and approximately 30% to 50% of patients with primary colon cancer will relapse and die of metastatic cancer. The 5-year survival rate of metastatic colorectal cancer remains disappointing at approximately 10%.Angiogenesis plays a significant role in tumor growth and metastasis in colorectal carcinoma. There are currently 4 US Food and Drug Administration-approved antiangiogenic agents for metastatic colorectal cancer. Bevacizumab is the only antiangiogenic agent approved by the US Food and Drug Administration for first-line treatment of metastatic colorectal cancer. Other antiangiogenic agents include ramucirumab, ziv-aflibercept, and regorafenib. We review the data supporting the use of antiangiogenics in this disease.

The Role of Angiogenesis Inhibitors in Hypertension: Following "Ariadne's Thread"

Arterial hypertension (HT) is one of the most frequently recorded comorbidities among patients under antiangiogenic therapy. Inhibitors of vascular endothelial growth factor and vascular endothelial growth factor receptors are most commonly involved in new onset or exacerbation of pre-existing controlled HT. From the pathophysiology point of view, data support that reduced nitric oxide release and sodium and fluid retention, microvascular rarefaction, elevated vasoconstrictor levels, and globular injury might contribute to HT. The purpose of this review was to present recent evidence regarding the incidence of HT induced by antiangiogenic agents, to analyze the pathophysiological mechanisms, and to summarize current recommendations for the management of elevated blood pressure in this field.

Molecular targeted treatment of metastatic colorectal cancer: the cardiovascular adverse effects of Bevacizumab and Cetuximab

Novel emerging therapies have changed paradigms in metastatic colorectal cancer. The advantages of molecular targeted treatments, either the anti-angiogenic or the anti-epidermal growth factor receptor drugs, reside in the fact that while their specificity for the cancer cell is higher, their toxicity on normal tissues is significantly lower when compared to chemotherapy. But when it comes to their safety, especially from a cardiovascular point of view, they still need to pass the test of time and further prospective studies are needed. Clinical trial patients are very well selected with regards to comorbidities and therefore, they often differ from real-life patients. In order to maximize the benefits from these drugs, we need to better identify the population at risk, understand and early diagnose their on- and off-target adverse effects and to adequately choose the diagnostic tools; with a better prevention and early treatment, the quality and quantity of our patients' lives can be significantly improved.

Bevacizumab with preoperative chemotherapy versus preoperative chemotherapy alone for colorectal cancer liver metastases: a retrospective cohort study

This study aimed to assess the efficacy and safety of bevacizumab plus preoperative chemotherapy as first-line treatment for liver-only metastatic colorectal cancer in Chinese patients compared with those of preoperative chemotherapy alone.Patients with histologically confirmed liver-only metastatic colorectal cancer were sequentially reviewed, and received either preoperative chemotherapy plus bevacizumab (bevacizumab group, n = 32) or preoperative chemotherapy alone (chemotherapy group, n = 57). Progression-free survival, response rate, liver resection rate, conversion rate, and safety were analyzed.With median follow-up of 28.7 months, progression-free survival was 10.9 months (95% confidence interval: 8.7-13.1 months) in bevacizumab group and 9.9 months (95% confidence interval: 6.8-13.1 months) in chemotherapy group (P = 0.472). Response rates were 59.4% in bevacizumab group and 38.6% in chemotherapy group (P = 0.059). Overall liver resection (R0, R1, and R2) rate was 68.8% in bevacizumab group and 54.4% in chemotherapy group (P = 0.185). Conversion rate was 51.9% in bevacizumab group and 40.4% in chemotherapy group (P = 0.341). No postoperative complication was observed in all patients.Bevacizumab plus preoperative chemotherapy as first-line treatment for liver-only metastatic colorectal cancer tends to achieve better clinical benefit with controllable safety in Chinese patients.

Ocular Hypertension Following Intravitreal Antivascular Endothelial Growth Factor Therapy: Review of the Literature and Possible Role of Nitric Oxide

PURPOSE

To review the literature regarding ocular hypertension following intravitreal antivascular endothelial growth factor therapy, and to propose a novel mechanism for the development of ocular hypertension as a result of such therapy.

METHODS

The PubMed database was used to identify publications by using combinations of the search terms, "glaucoma," "ocular hypertension," "pegaptanib," "bevacizumab," "ranibizumab," "aflibercept," "anti-vascular endothelial growth factor," intraocular pressure," and "intravitreal." The reference lists of these publications were also reviewed for relevant articles.

RESULTS

Numerous articles have been published describing ocular hypertension, either immediate-term/short-term or delayed/sustained, following intravitreal antivascular endothelial growth factor therapy. Ocular hypertension has been reported following intravitreal pegaptanib, bevacizumab, and ranibizumab, and aflibercept. On the basis of the fact that vascular endothelial growth factor, normally present as a vascular modulating and reparative growth factor, is known to upregulate endothelial nitric oxide (NO) synthase, and that NO has been shown to decrease intraocular pressure in both normal and glaucomatous human and animal eyes, we propose a novel mechanism for sustained ocular hypertension following intravitreal antivascular endothelial growth factor therapy. We propose that such intravitreal therapy may lead to decreased NO in the anterior segment, which then leads to trabecular meshwork constriction, decreased outflow facility, and increased intraocular pressure.

CONCLUSIONS

Sustained ocular hypertension following the intravitreal administration of antivascular endothelial growth factor agents is a potentially serious side effect that has not been adequately explained. Further investigation is necessary to determine the role of NO in the mediation of this adverse effect.

Current and advancing treatments for metastatic colorectal cancer

INTRODUCTION

Colorectal cancer (CRC) is one of the leading causes of cancer deaths worldwide. Despite the introduction of several new drugs targeting the vascular endothelial growth factor or epidermal growth factor receptor (EGFR) signaling pathways, survival and disease control in metastatic CRC remains poor.

AREAS COVERED

Chemotherapy based on fluoropyrimidines and irinotecan or oxaliplatin has been the cornerstone of CRC standard of care for several decades. Optimal regimens are selected according to toxicity profiles and patient characteristics. The addition of targeted drugs inhibiting angiogenesis, notably bevacizumab, aflibercept and ramucirumab, has improved chemotherapy outcomes in metastatic CRC. Anti-EGFR agents, cetuximab and panitumumab, in combination with chemotherapy have also improved survival in patients with wild-type RAS tumors. In the refractory setting, there are emerging drugs such as regorafenib or TAS-102 that also have demonstrated impact on outcomes.

EXPERT OPINION

Drugs targeting signaling pathways involved in tumorigenesis improve patient outcomes over chemotherapy alone. Determining the most suitable combination and sequence should be carefully selected, with studies yet to provide a definitive solution to this unknown. Molecular mechanisms of colorectal cancer are at the forefront of research. Knowledge in this domain will help overcome resistance to therapies and introduce new drugs in the personalized CRC therapeutic scenario.

Cancer therapy and cardiovascular risk: focus on bevacizumab

Recognition and management of treatment-related cardiovascular toxicity, defined as either an acute cardiac event or a chronic condition, has been tightly integrated into routine cancer care and has become an important component in treatment selection. Several chemotherapeutic agents, such as anthracyclines, are traditionally characterized as cardiotoxic, but cardiovascular adverse events are also associated with commonly used molecular targeted therapies. In the past decade, bevacizumab, a monoclonal humanized antibody against vascular endothelial growth factor, has been introduced in the treatment of a variety of metastatic malignancies. Despite its efficacy, bevacizumab has been associated with significant risk of cardiovascular complications, such as hypertension, cardiac ischemia, and congestive heart failure. This review will focus on the cardiovascular toxicity of bevacizumab, providing the latest evidence on the incidence, clinical spectrum, risk factors, and responsible mechanisms.

Molecular Connections between Cancer Cell Metabolism and the Tumor Microenvironment

Cancer cells preferentially utilize glycolysis, instead of oxidative phosphorylation, for metabolism even in the presence of oxygen. This phenomenon of aerobic glycolysis, referred to as the “Warburg effect”, commonly exists in a variety of tumors. Recent studies further demonstrate that both genetic factors such as oncogenes and tumor suppressors and microenvironmental factors such as spatial hypoxia and acidosis can regulate the glycolytic metabolism of cancer cells. Reciprocally, altered cancer cell metabolism can modulate the tumor microenvironment which plays important roles in cancer cell somatic evolution, metastasis, and therapeutic response. In this article, we review the progression of current understandings on the molecular interaction between cancer cell metabolism and the tumor microenvironment. In addition, we discuss the implications of these interactions in cancer therapy and chemoprevention.

An observational study of nasal cavity toxicity in cancer patients treated with bevacizumab

BACKGROUND

The nasal cavity is a vulnerable zone which may be damaged by vascular disorders. We systematically assessed the frequency and severity of nasal cavity alterations during bevacizumab treatment, to determine its clinical relevance and factors contributing to its onset.

PATIENTS AND METHODS

We conducted a hospital-based cohort study in 47 consecutive patients with advanced cancers who were on treatment with chemotherapy and bevacizumab at different doses. All patients underwent otolaryngology (ENT) examination at the time of study initiation.

RESULTS

The mean number of cycles at first ENT examination was 16 (standard deviation = 14). A total of 45 patients (96%) showed nose mucosal lesions, of whom 30% had erosions and 62% had grade 1 - 2 epistaxis. One patient had septal perforation. Grades 1 - 4 sinus disorders were noted in 60%. There was a significant trend to a higher risk of grade ≥ 2 nasal events for bevacizumab doses > 7.5 mg/kg, concomitant taxane use and digital nasal self-manipulation.

CONCLUSIONS

We found a high incidence of nasal cavity lesions in patients receiving bevacizumab, with evidence for a dose-related effect. Most cases were low grade and manageable without drug interruption, but severe toxicity may rarely occur. Oncologists should be aware of this unusual event.

Natural history of hepatic metastases from colorectal cancer - pathobiological pathways with clinical significance

Colorectal cancer hepatic metastases represent the final stage of a multi-step biological process. This process starts with a series of mutations in colonic epithelial cells, continues with their detachment from the large intestine, dissemination through the blood and/or lymphatic circulation, attachment to the hepatic sinusoids and interactions with the sinusoidal cells, such as sinusoidal endothelial cells, Kupffer cells, stellate cells and pit cells. The metastatic sequence terminates with colorectal cancer cell invasion, adaptation and colonisation of the hepatic parenchyma. All these events, termed the colorectal cancer invasion-metastasis cascade, include multiple molecular pathways, intercellular interactions and expression of a plethora of chemokines and growth factors, and adhesion molecules, such as the selectins, the integrins or the cadherins, as well as enzymes including matrix metalloproteinases. This review aims to present recent advances that provide insights into these cell-biological events and emphasizes those that may be amenable to therapeutic targeting.

An updated meta-analysis of fatal adverse events caused by bevacizumab therapy in cancer patients

Background

The risk of fatal adverse events (FAEs) due to bevacizumab-based chemotherapy has not been well described; we carried out an updated meta-analysis regarding this issue.

Methods

An electronic search of Medline, Embase and The Cochrane Central Register of Controlled Trials was conducted to investigate the effects of randomized controlled trials on bevacizumab treatment on cancer patients. Random or fixed-effect meta-analytical models were used to evaluate the risk ratio (RR) of FAEs due to the use of bevacizumab.

Results

Thirty-four trials were included. Allocation to bevacizumab therapy significantly increased the risk of FAEs; the RR was 1.29 (95% CI:1.05–1.57). This association varied significantly with tumor types (P = 0.002) and chemotherapeutic agents (P = 0.005) but not with bevacizumab dose (P = 0.90). Increased risk was seen in patients with non–small cell lung cancer, pancreatic cancer, prostate cancer, and ovarian cancer. However, FAEs were lower in breast cancer patients treated with bevacizumab. In addition, bevacizumab was associated with an increased risk of FAEs in patients who received concomitant agents of taxanes and/or platinum.

Conclusion

Compared with chemotherapy alone, the addition of bevacizumab was associated with an increased risk of FAEs among patients with special tumor types, particularly when combined with chemotherapeutic agents such as platinum.

Hypertension due to antiangiogenic cancer therapy with vascular endothelial growth factor inhibitors: understanding and managing a new syndrome

Novel antiangiogenic cancer therapies, particularly agents that block vascular endothelial growth factor (VEGF) signalling, have improved outcomes in patients with cancers and are now used as first-line therapies for some tumours. However, with VEGF inhibitors (VEGFIs) are new complications, particularly hypertension. VEGFI-induced hypertension is a dose-dependent phenomenon due to on-target effects rather than off-target effects. Increased blood pressure occurs in almost 100% of patients who take VEGFIs, with a subset who develop severe hypertension. Molecular mechanisms underlying VEGFI-induced hypertension are unclear, but endothelial dysfunction and increased vascular resistance, due to impaired nitric oxide signalling, reduced prostacyclin production, endothelin-1 (ET-1) upregulation, oxidative stress, and rarefaction have been implicated. Treatment of hypertension should be aimed at reducing the risk of short-term morbidity associated with hypertension while maintaining effective dosing of antiangiogenic therapy for optimal cancer treatment. Although specific guidelines are not yet available for the management of VEGFI-induced hypertension, angiotensin-converting enzyme inhibitors and dihydropyridine calcium channel blockers are commonly used. Severe hypertension might require reduction of VEGFI dosing, or in some cases, interruption of treatment. As more potent VEGFIs are developed and as more cancer patients are treated with VEGFIs, the burden of hypertension toxicity will increase. This will be further compounded as the use of antiangiogenic drugs broadens to include older patients and those with pre-existing cardiovascular disease. Here we focus on VEGF as a target for antiangiogenesis and how this affects increased blood pressure. Putative mechanisms underlying VEGFI-induced hypertension are highlighted and therapeutic strategies to manage such hypertension are discussed.

An analysis of radiation necrosis of the central nervous system treated with bevacizumab

Radiation necrosis is a devastating complication following radiation to the central nervous system. The purpose of this study was to perform a comprehensive analysis of cases in the literature using bevacizumab, a monoclonal antibody against vascular endothelial growth factor, as treatment for radiation necrosis. A MEDLINE/PubMed search of articles about the use of bevacizumab for radionecrosis treatment yielded 16 studies published between 2007 and 2012. Data was summarized according to patient characteristics, treatment received and outcomes measured. A total of 71 unique cases were identified that met the inclusion criteria. The median age at the time of treatment with bevacizumab was 47 years. The most common tumors treated were glioblastoma (31 %), anaplastic glioma (14 %), and metastatic brain tumors (15 %). The median time from ending radiotherapy to starting treatment with bevacizumab was 11 months and the median follow up time after bevacizumab treatment was 8 months. The median number of cycles of bevacizumab was administered was 4, and the median dosage of bevacizumab was 7.5 mg/kg. The median time elapsed between cycles of bevacizumab was 2 weeks. Overall, pre and post treatment imaging revealed a median decrease in T1 contrast enhancement of 63 %, and a 59 % median decrease in T2/FLAIR signal abnormality. Treatment with bevacizumab resulted in a significant radiographic response for patients with radionecrosis. The median dosage of bevacizumab of 7.5 mg/kg for four cycles every 2 weeks should be considered as a treatment option in this patient population.