Immunoregulation mechanism of VEGF signaling pathway inhibitors and its efficacy on the kidney

Angiogenesis and immunosuppression are closely related pathophysiologic processes. Widely prescribed in malignant tumor and proliferative retinal lesions, VEGF signaling pathway inhibitors may cause hypertension and renal injury in some patients, presenting with proteinuria, nephrotic syndrome, renal failure and thrombotic microangiopathy. VEGF signaling pathway inhibitors block the action of both VEGF-A and VEGF-C. However, VEGF-A and VEGF-C produced by podocytes are vital to maintain the physiological function of glomerular endothelial cells and podocytes. There is still no effective treatment for kidney disease associated with VEGF signaling pathway inhibitors and some patients have progressive renal failure even after withdrawal of the drug. Recent studies reveal that blocking of VEGF-A and VEGF-C can activate CD4 +and CD8+ T cells, augment antigen-presenting function of dendritic cells, enhance cytotoxicity of macrophages and initiate complement cascade activation. VEGF and VEGFR are expressed in immune cells, which are involved in the immunosuppression and cross-talk among immune cells. This review summarizes the expression and function of VEGF-A and VEGF-C in the kidney. The current immunoregulation mechanisms of VEGF signaling pathway inhibitors are reviewed. Finally, combinate strategies are summarized to highlight the proposal for VEGF signaling pathway inhibitors.

A case of multiple hepatocellular carcinoma experiencing complete responses to sorafenib and atezolizumab-bevacizumab and developing severe, refractory venous congestive cutaneous ulcers on either regimen

A man in his eighties presented with a history of bilateral leg congestive phlebitis, and multiple hepatocellular carcinoma (HCC) treated with sorafenib. When the dose was increased to 400 mg, ulcers appeared under both knees, which worsened, and the drug was discontinued 2 months after administration. However, the ulcers to 30 mm in diameter, requiring debridement and antibiotics. The HCC showed a complete response (CR) based on modified-RECIST criteria; however, after several rounds of locoregional therapy for recurrence, multiple HCCs and metastatic lesions in the Morrison's fossa were detected. Therefore, atezolizumab 1200 mg-bevacizumab 900 mg was started. After the first course, the patient complained of pain below both knees, and when the second course was administered, leg ulcers re-appeared and rapidly worsened. The ulcers were circular and multiple and progressed to deep digging, leading to tendon exposure. Bevacizumab-induced congestive venous ulcer was diagnosed, requiring skin grafts to heal. HCC then showed a CR based on m-RECIST criteria. Initially, the cause of the ulcer was thought to be immune-related adverse effects due to atezolizumab, but experience with sorafenib led us to conclude that the cause was stagnant venous ulcers due to vascular endothelial growth factor receptor inhibitor, which inhibited angiogenesis.

Conditional catheter-related thrombosis free probability and risk-adapted choices of catheter for lung cancer

Background

Current predictive tools assess catheter‐related thrombosis (CRT) in patients with lung cancer in a static manner at a single time point of catheterization. The subsequent hazard changes over time are unknown. The conditional catheter‐related thrombosis‐free probability (CCFP) can provide dynamic information on continual CRT‐free expectations. This study aimed to assess the CCFP and hazard rates based on risk categories and various venous access devices (VADs).

Methods

This retrospective study reviewed 939 patients with lung cancer with peripherally inserted central venous catheters (PICCs) or central venous catheters (CVCs) identified at the National Clinical Research Center for Cancer between January 1, 2015 and December 31, 2018. The incidence of CRT has also been reported. Patients were stratified into low‐ and high‐risk groups according to multivariate Cox regression analyses. CCFP is defined as the CRT‐free probability given that patients have no CRT for a definite time.

Results

A total of 507 patients with PICCs and 432 patients with CVCs were included in this study. The 3‐month CCFP increased from 74.2% at catheter insertion to 93.6% at 3 months. The hazards of CRT in the first month were highest (16.4%) and slightly thereafter. The high‐risk group initially had a higher (21.4%) but significantly decreased CRT hazard after 2 months (8.3%), whereas the low‐risk group maintained a comparable lower risk hazard of less than 5% after 1 month. In the overall cohort, patients with CVCs had lower CRT probability than those with PICCs (HR, 1.76; 95% CI: 1.28–2.41; p < 0.01). Further analysis demonstrated that compared with PICCs, CVCs provided a CRT‐free benefit in low‐risk patients (p = 0.02) but not in high‐risk patients (p = 0.06).

Conclusions

CCFP increased, and the hazards of CRT decreased over time in a risk‐dependent manner in patients with lung cancer. These valuable dynamic data may help optimize risk‐adjusted choices of VADs and risk‐adjusted prophylactic anticoagulation strategies for patients.

Bevacizumab-induced atypical hemolytic uremic syndrome and treatment with eculizumab

Bevacizumab (Avastin) is a recombinant humanized monoclonal antibody used for the management of various solid malignancies including colorectal, lung, brain, renal, and ovarian cancers as well as age-related macular degeneration of the eye. It is a vascular endothelial growth factor inhibitor which exhibits its action by blocking the growth of blood vessels in cancerous tissue. Common side effects include hypertension, fatigue, headaches, and increased risk of infections. Atypical hemolytic uremic syndrome is a serious side effect associated with bevacizumab due to its anti-angiogenic effect. It encompasses the clinical triad of thrombocytopenia, microangiopathic hemolytic anemia, and acute renal failure, without any association with Shiga toxins. Eculizumab is a terminal complement inhibitor used in the treatment of atypical hemolytic uremic syndrome. Herein, we present three cases of bevacizumab-induced atypical hemolytic syndrome treated successfully with eculizumab.

[Embolic stroke immediately after initial administration of intravitreal aflibercept]

A 72-year-old man was admitted to our hospital because of right upper limb monoplegia 8 hours after the initial intravitreal injection of aflibercept, which is an inhibitor of vascular endothelial growth factor. Magnetic resonance diffusion-weighted images showed recent ischemic lesions in the left corona radiata and the right superior frontal gyrus. Laboratory findings showed mild hyperfibrinolysis. A patent foramen ovale was diagnosed on transesophageal echocardiography; however, lower-extremity ultrasonography did not detect deep vein thrombosis. The source of embolism remained unknown. A possible mechanism of cerebral emboli in the present case was a rapidly induced hypercoagulative state due to transfer of aflibercept from the vitreous body to the systemic circulation.