Pancreatic ductal adenocarcinoma: Emerging therapeutic strategies

The seventh leading cause of cancer-related death globally, pancreatic ductal adenocarcinoma (PDAC) involves the exocrine pancreas and constitutes greater than 90% of all pancreatic cancers. Surgical resection in combination with systemic chemotherapy with or without radiation remains the mainstay of treatment and the only potentially curative treatment option. While there has been improvement in systemic chemotherapy, long-term survival among patients with PDAC remains poor. Improvement in the understanding of tumorigenesis, genetic mutations, the tumor microenvironment (TME), immunotherapies, as well as targeted therapies continued to drive advances in PDAC treatment. We herein review the TME, genetic landscape, as well as various metabolic pathways associated with PDAC tumorigenesis relative to emerging therapies.     

阿托伐他汀对大脑中动脉栓塞大鼠尿激酶溶栓治疗的影响

目的研究阿托伐他汀联合尿激酶溶栓对大鼠大脑中动脉急性脑梗死的疗效。方法选择SD大鼠48只,采用血栓栓塞法制备大鼠大脑中动脉急性脑梗死模型,随机分为阿托伐他汀组、尿激酶组、联合治疗组和对照组,每组12只。缺血3h给予阿托伐他汀或生理盐水,缺血4h给予尿激酶或生理盐水治疗。治疗前和缺血24h行神经功能缺损评分,缺血24h取脑行2,3,5-氯化三苯基四氮唑染色检测脑梗死体积。结果与对照组比较,阿托伐他汀组缺血24h神经功能显著改善[(6.5±4.3)分vs(12.5±4.3)分],脑梗死体积明显降低[(13.8±7.5)%vs(30.5±23.4)%,P<0.05]。与阿托伐他汀组比较,尿激酶组和联合治疗组神经功能改善程度及脑梗死体积降低程度更显著(P<0.05)。与尿激酶组比较,联合治疗组神经功能改善、脑梗死体积减小,但差异无统计学意义(P>0.05)。结论阿托伐他汀对脑梗死组织有保护作用,阿托伐他汀与尿激酶联合治疗有进一步提高疗效的趋势。     

Are Hypomethylating Agents Replacing Induction-Type Chemotherapy before Allogeneic Stem Cell Transplantation in Patients with Myelodysplastic Syndrome?

Cytoreductive treatment before allogeneic hematopoietic stem cell transplantation (allo-SCT) with the objective of reducing the incidence of disease relapse post-transplant in patients with myelodysplastic syndrome (MDS) is a matter of debate. The achievement of complete remission (CR) before allo-SCT improves post-transplantation outcome, although it is not clear whether this reflects the selection of patients with more responsive disease or is related to a reduction in disease burden. Higher CR rates in patients with MDS are obtained with induction chemotherapy (ICT) than with hypomethylating agents (HMAs), although HMAs may be active in patients with complex karyotypes in whom ICT almost invariably fails. Furthermore, HMAs have a good toxicity profile compared with ICT and may therefore be considered especially in older patients and in patients with comorbidities. However, all interventions aimed at reducing disease burden before allo-SCT expose patients to the risk of complications, which may prevent them from undergoing transplantation. Therefore, up-front allo-SCT is an option, particularly for patients with life-threatening cytopenias. In this review we discuss the main pretransplant therapeutic approaches and propose a decision-model based on clinical considerations. However, only prospective randomized trials can address the issue definitively.     

Donor‐Derived Strongyloides stercoralis Infection in Solid Organ Transplant Recipients in the United States, 2009–2013

Infection with Strongyloides stercoralis is typically asymptomatic in immunocompetent hosts, despite chronic infection. In contrast, immunocompromised hosts such as solid organ transplant recipients are at risk for hyperinfection syndrome and/or disseminated disease, frequently resulting in fatal outcomes. Infection in these recipients may result from reactivation of latent infection or infection through transmission from an infected donor. We describe the Centers for Disease Control and Prevention's experience with seven clusters of donor‐derived infection from 2009 to 2013. Six of the seven (86%) donors were born in Latin America; donor screening was not performed prior to organ transplantation in any of these investigations. Eleven of the 20 (55%) organ recipients were symptomatic, two of whom died from complications of strongyloidiasis. We also describe the New York Organ Donor Network (NYODN) experience with targeted donor screening from 2010 to 2013. Of the 233 consented potential donors tested, 10 tested positive for Strongyloides antibody; and 18 organs were transplanted. The majority (86%) of the donors were born in Central or South America. Fourteen recipients received prophylaxis after transplantation; no recipients developed strongyloidiasis. The NYODN experience provides evidence that when targeted donor screening is performed prior to transplantation, donor‐derived infection can be averted in recipients.     

Emerging Issues With Diagnosis and Management of Fungal Infections in Solid Organ Transplant Recipients

Invasive fungal infections (IFIs) are being increasingly recognized in solid organ transplant (SOT) recipients, and delayed diagnosis can lead to graft loss and death. Therefore, there is a low threshold for prophylaxis and early initiation of empiric antifungal treatment, in this patient population. Meanwhile, the increasing consumption of antifungals is associated with high cost, medication toxicities and the emergence of resistance in Candida species, all of which call for rational use of antifungal agents. The implementation of fungal biomarkers, molecular diagnostic methods and direct detection of volatile fungal metabolites in breath samples could lead to faster diagnosis, early appropriate treatment and improved clinical outcomes, but also aid in the de‐escalation of antifungal treatment. Those novel diagnostic modalities need to be validated specifically in SOT recipients. Infectious diseases consultation can contribute to optimization of care through prompt initiation and appropriate modification of antifungal treatment, management of medication toxicities and drug‐drug interactions, as well as source control. In this review, we conceptually summarize recent advances in the diagnosis and management of IFI in SOT recipients, and highlight the importance of early diagnostic tools and good stewardship of antifungal drugs.