Outcomes of early hospital readmission after kidney transplantation: Perspectives from a Canadian transplant centre.

BACKGROUND: Early hospital readmissions (EHRs) after kidney transplantation range in incidence from 18%-47% and are important and substantial healthcare quality indicators. EHR can adversely impact clinical outcomes such as graft function and patient mortality as well as healthcare costs. EHRs have been extensively studied in American healthcare systems, but these associations have not been explored within a Canadian setting. Due to significant differences in the delivery of healthcare and patient outcomes, results from American studies cannot be readily applicable to Canadian populations. A better understanding of EHR can facilitate improved discharge planning and long-term outpatient management post kidney transplant. AIM: To explore the burden of EHR on kidney transplant recipients (KTRs) and the Canadian healthcare system in a large transplant centre. METHODS: This single centre cohort study included 1564 KTRs recruited from January 1, 2009 to December 31, 2017, with a 1-year follow-up. We defined EHR as hospitalizations within 30 d or 90 d of transplant discharge, excluding elective procedures. Multivariable Cox and linear regression models were used to examine EHR, late hospital readmissions (defined as hospitalizations within 31-365 d for 30-d EHR and within 91-365 d for 90-d EHR), and outcomes including graft function and patient mortality. RESULTS: In this study, 307 (22.4%) and 394 (29.6%) KTRs had 30-d and 90-d EHRs, respectively. Factors such as having previous cases of rejection, being transplanted in more recent years, having a longer duration of dialysis pretransplant, and having an expanded criteria donor were associated with EHR post-transplant. The cumulative probability of death censored graft failure, as well as total graft failure, was higher among the 90-d EHR group as compared to patients with no EHR. While multivariable models found no significant association between EHR and patient mortality, patients with EHR were at an increased risk of late hospital readmissions, poorer kidney function throughout the 1st year post-transplant, and higher hospital-based care costs within the 1st year of follow-up. CONCLUSION: EHRs are associated with suboptimal outcomes after kidney transplant and increased financial burden on the healthcare system. The results warrant the need for effective strategies to reduce post-transplant EHR.

Uterine Sarcoma With FGFR1-TACC1 Gene Fusion: A Case Report and Review of the Literature.

With the growing availability of RNA sequencing technology in the pathology laboratory, new gene fusion-associated malignancies are increasingly being characterized. In this article, we describe the second ever reported case of a uterine sarcoma harboring a FGFR1-TACC1 gene fusion. The patient, a 53-yr-old perimenopausal woman, was found to have a 6 cm mass spanning the lower uterine segment and endocervix. Histologically, this was a spindle cell neoplasm with coagulative necrosis, moderate cytologic atypia, and increased mitotic activity. By immunohistochemistry, the neoplastic cells coexpressed CD34 and S100, and lacked smooth muscle marker expression. RNA sequencing revealed the presence of a FGFR1-TACC1 gene fusion. This report provides further evidence to suggest that FGFR1-TACC1 may be a recurrent fusion in a subset of uterine sarcomas. RNA sequencing using a panel that includes FGFR-TACC family fusions should be considered for uterine sarcomas that do not fit conventional diagnostic criteria, particularly as tumors with these fusions may be amenable to targeted therapy.

Barrett's Esophagus and Esophageal Adenocarcinoma: A Histopathological Perspective.

Esophageal adenocarcinoma (EAC) is increasing in prevalence. Barrett's esophagus (BE) has long been recognized as the putative precursor lesion for EAC, but much is still unknown regarding its cell of origin and what molecular factors influence its neoplastic progression. Accurate pathologic assessment of BE biopsies is important for identifying patients most at risk of progressing to EAC, whereas pathologic assessment of EAC specimens plays a major role in influencing therapeutic decision-making.

Gene of the month: STK11.

STK11 encodes for the protein liver kinase B1, a serine/threonine kinase which is involved in a number of physiological processes including regulation of cellular metabolism, cell polarity and the DNA damage response. It acts as a tumour suppressor via multiple mechanisms, most classically through AMP-activated protein kinase-mediated inhibition of the mammalian target of rapamycin signalling pathway. Germline loss-of-function mutations in STK11 give rise to Peutz-Jeghers syndrome, which is associated with hamartomatous polyps of the gastrointestinal tract, mucocutaneous pigmentation and a substantially increased lifetime risk of many cancers. In the sporadic setting, STK11 mutations are commonly seen in a subset of adenocarcinomas of the lung in addition to a number of other tumours occurring at various sites. Mutations in STK11 have been associated with worse prognoses across a range of malignancies and may be a predictor of poor response to immunotherapy in a subset of lung cancers, though further studies are needed before the presence of STK11 mutations can be implemented as a routine clinical biomarker.

Gene of the month: FH.

Fumarate hydratase (FH), encoded by the FH gene, is an enzyme which catalyses the conversion of fumarate to L-malate as part of the tricarboxylic acid cycle. Biallelic germline mutations in FH result in fumaric aciduria, a metabolic disorder resulting in severe neurological and developmental abnormalities. Heterozygous germline mutations in FH result in hereditary leiomyomatosis and renal cell carcinoma, a cancer predisposition syndrome. FH deficiency has multiple oncogenic mechanisms including through promotion of aerobic glycolysis, induction of pseudohypoxia, post-translational protein modification and impairment of DNA damage repair by homologous recombination. FH-deficient neoplasms can present with characteristic morphological features that raise suspicion for FH alterations and also frequently demonstrate loss of FH immunoreactivity and intracellular accumulation of 2-succinocysteine, also detected by immunohistochemistry.

MLH1 epimutation is a rare mechanism for Lynch syndrome: A case report and review of the literature.

Endometrial carcinoma is one of the prototypical malignancies associated with Lynch syndrome, an inherited cancer syndrome most commonly caused by germline mutations in DNA mismatch repair (MMR) genes, although rare alternative mechanisms also exist. In this report, we describe a patient first diagnosed with colorectal cancer at age 33, then vulvar squamous cell carcinoma, facial sebaceous adenoma/sebaceoma, and finally endometrial carcinoma at age 52. All tumors were MLH1/PMS2-deficient by immunohistochemistry, and MLH1 promoter methylation was identified in the endometrial cancer. Germline MLH1 testing was negative for pathogenic variants, but she was subsequently diagnosed with Lynch syndrome secondary to a germline monoallelic constitutional epimutation of the MLH1 promoter. Identification of patients displaying a Lynch syndrome phenotype but lacking germline MMR mutations is important to avoid delays in the diagnosis of Lynch syndrome as well as the initiation of appropriate cancer screening and genetic counseling.

What Are the Burden, Causes, and Costs of Early Hospital Readmissions After Kidney Transplantation?

INTRODUCTION: Kidney transplant recipients are at risk for complications resulting in early hospital readmission. This study sought to determine the incidences, risk factors, causes, and financial costs of early readmissions. DESIGN: This single-centre cohort study included 1461 kidney recipients from 1 Jul 2004 to 31 Dec 2012, with at least 1-year follow-up. Early readmission was defined as hospitalization within 30 or 90-days postdischarge from transplant admission. Associations between various parameters and 30 and 90-days posttransplant were determined using multivariable Cox proportional hazards models. The hospital-associated costs of were assessed. RESULTS: The rates of early readmission were 19.4% at 30 days and 26.8% at 90 days posttransplant. Mean cost per 30-day readmission was 11 606 CAD. Infectious complications were the most common reasons and resulted in the greatest cost burden. Factors associated with 30 and 90-days in multivariable models were recipient history of chronic lung disease (hazard ratio or HR 1.78 [95%CI: 1.14, 2.76] and HR 1.68 [1.14, 2.48], respectively), median time on dialysis (HR 1.07 [95% CI: 1.01, 1.13]and HR 1.06 [95% CI: 1.01, 1.11], respectively), being transplanted preemptively (HR 1.75 [95% CI: 1.07, 2.88] and HR 1.66 [95% CI: 1.07, 2.57], respectively), and having a transplant hospitalization lasting of and more than 11 days (HR 1.52 [95% CI: 1.01, 2.27] and HR 1.65 [95% CI: 1.16, 2.34], respectively). DISCUSSION: Early hospital readmission after transplantation was common and costly. Strategies to reduce the burden of early hospital readmissions are needed for all patients.

CTNNB1 Mutations and Aberrant ß-Catenin Expression in Ovarian Endometrioid Carcinoma: Correlation With Patient Outcome.

CTNNB1 mutations and aberrant ß-catenin expression have adverse prognosis in endometrial endometrioid carcinoma, and recent evidence suggests a prognostic role of ß-catenin in ovarian endometrioid carcinoma. Thus, we aimed to determine the prognostic value of the CTNNB1 mutational status, and its correlation with ß-catenin expression, in a well-annotated cohort of 51 ovarian endometrioid carcinomas. We performed immunohistochemistry for ß-catenin and developed an 11-gene next-generation sequencing panel that included whole exome sequencing of CTNNB1 and TP53. Results were correlated with clinicopathologic variables including disease-free and disease-specific survival. Tumor recurrence was documented in 14 patients (27%), and cancer-related death in 8 patients (16%). CTNNB1 mutations were found in 22 cases (43%), and nuclear ß-catenin in 26 cases (51%). CTNNB1 mutation highly correlated with nuclear ß-catenin (P<0.05). Mutated CTNNB1 status was statistically associated with better disease-free survival (P=0.04, log-rank test) and approached significance for better disease-specific survival (P=0.07). It also correlated with earlier International Federation of Gynecology and Obstetrics stage (P<0.05). Nuclear ß-catenin, TP53 mutations, age, ProMisE group, surface involvement, tumor grade and stage also correlated with disease-free survival. There was no association between membranous ß-catenin expression and disease-free or disease-specific survival. CTNNB1 mutations and nuclear ß-catenin expression are associated with better progression-free survival in patients with OEC. This relationship may be in part due to a trend of CTNNB1-mutated tumors to present at early stage. ß-catenin immunohistochemistry may serve as a prognostic biomarker and a surrogate for CTNN1B mutations in the evaluation of patients with ovarian endometrioid neoplasia, particularly those in reproductive-age or found incidentally without upfront staging surgery.

The prognostic role of horizontal and circumferential tumor extent in cervical cancer: Implications for the 2019 FIGO staging system.

OBJECTIVE: The FIGO 2019 update on cervical cancer staging removed horizontal tumor extent (HZTE) as a staging variable. Evidence is needed to substantiate this change. The prognostic significance of HZTE and a related variable, circumferential tumor extent (%CTE), is similarly unknown. We aimed to investigate the association of HZTE and %CTE with survival outcomes in cervical cancer patients. METHODS: We identified patients treated with primary surgery for stage I cervical cancer in a single institution during a 9-year period. HZTE and, when available, %CTE were obtained from pathology records. Cases were staged using 2019 FIGO staging. Correlations between HZTE, %CTE and FIGO stage with recurrence-free (RFS) and disease-specific survival (DSS) were determined using univariable and multivariable analyses. RESULTS: 285 patients were included with a median follow-up of 48 (range 7-123) months. HZTE was statistically associated with RFS and DSS on univariate and multivariate analysis. None of the 168 stage IA patients in our series had tumor recurrence or death during follow-up, including 42 with HZTE ≥7 mm. None of the patients with a tumor horizontal extent <7 mm experienced recurrence or death. %CTE correlated only with RFS on univariate analysis. 2019 FIGO stage did not independently correlate with RFS or DSS in our sample. CONCLUSIONS: HZTE is an independent predictor of survival in cervical carcinoma. In stage IA tumors, however, HZTE does not offer superior prognostic value, supporting the 2019 FIGO recommendations to remove this variable from staging in these cases. HZTE may be useful in larger tumors in which staging depends on maximum tumor size. %CTE is not an independent prognostic variable in cervical cancer, and we advise against its use.

Risk Factors for 1-Year Graft Loss After Kidney Transplantation: Systematic Review and Meta-Analysis.

BACKGROUND AND OBJECTIVES: With expansion of the pool of kidney grafts, through the use of higher-risk donors, and increased attention to donor management strategies, the 1-year graft survival rate is subject to change. It is, therefore, useful to elucidate 1-year graft survival rates by dissecting the characteristics of the low-risk and high-risk kidney transplant cases. The objective of our study was to evaluate factors purported to influence the risk of 1-year graft loss in kidney transplant recipients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We searched bibliographic databases from 2000 to 2017 and included observational studies that measured the association between donor, recipient, the transplant operation, or early postoperative complications, and 1-year death-censored graft loss. RESULTS: We identified 35 eligible primary studies, with 20 risk factors amenable to meta-analysis. Six factors were associated with graft loss, with moderate to high degree of certainty: donor age (hazard ratio [HR], 1.11 per 10-year increase; 95% confidence interval [95% CI], 1.04 to 1.18), extended criteria donors (HR, 1.35; 95% CI, 1.28 to 1.42), deceased donors (HR, 1.54; 95% CI, 1.32 to 1.82), number of HLA mismatches (HR, 1.08 per one mismatch increase; 95% CI, 1.07 to 1.09), recipient age (HR, 1.17 per 10-year increase; 95% CI, 1.09 to 1.25), and delayed graft function (HR, 1.89; 95% CI, 1.46 to 2.47) as risk factors for 1-year graft loss. Pooled analyses also excluded, with a high degree of certainty, any associations of cold ischemia time, recipient race, pretransplant body mass index, diabetes, and hypertension with 1-year graft loss. CONCLUSIONS: Recipient age, donor age, standard versus extended criteria donor, living versus deceased donor, HLA mismatch, and delayed graft function all predicted 1-year graft survival. The effect of each risk factor is small.

Influenza Virus Infection Induces Platelet-Endothelial Adhesion Which Contributes to Lung Injury.

Lung injury after influenza infection is characterized by increased permeability of the lung microvasculature, culminating in acute respiratory failure. Platelets interact with activated endothelial cells and have been implicated in the pathogenesis of some forms of acute lung injury. Autopsy studies have revealed pulmonary microthrombi after influenza infection, and epidemiological studies suggest that influenza vaccination is protective against pulmonary thromboembolism; however, the effect of influenza infection on platelet-endothelial interactions is unclear. We demonstrate that endothelial infection with both laboratory and clinical strains of influenza virus increased the adhesion of human platelets to primary human lung microvascular endothelial cells. Platelets adhered to infected cells as well as to neighboring cells, suggesting a paracrine effect. Influenza infection caused the upregulation of von Willebrand factor and ICAM-1, but blocking these receptors did not prevent platelet-endothelial adhesion. Instead, platelet adhesion was inhibited by both RGDS peptide and a blocking antibody to platelet integrin α5ß1, implicating endothelial fibronectin. Concordantly, lung histology from infected mice revealed viral dose-dependent colocalization of viral nucleoprotein and the endothelial marker PECAM-1, while platelet adhesion and fibronectin deposition also were observed in the lungs of influenza-infected mice. Inhibition of platelets using acetylsalicylic acid significantly improved survival, a finding confirmed using a second antiplatelet agent. Thus, influenza infection induces platelet-lung endothelial adhesion via fibronectin, contributing to mortality from acute lung injury. The inhibition of platelets may constitute a practical adjunctive strategy to the treatment of severe infections with influenza.IMPORTANCE There is growing appreciation of the involvement of the lung endothelium in the pathogenesis of severe infections with influenza virus. We have recently shown that the virus can infect human lung endothelial cells, but the functional consequences of this infection are unknown (S. M. Armstrong, C. Wang, J. Tigdi, X. Si, C. Dumpit, S. Charles, A. Gamage, T. J. Moraes, and W. L. Lee, PLoS One 7:e47323, 2012, http://dx.doi.org/10.1371/journal.pone.0047323). Here, we show that this infection causes platelets to adhere to the lung endothelium. Importantly, blocking platelets using two distinct antiplatelet drugs improved survival in a mouse model of severe influenza infection. Thus, platelet inhibition may constitute a novel therapeutic strategy to improve the host response to severe infections with influenza.

Clathrin-dependent entry and vesicle-mediated exocytosis define insulin transcytosis across microvascular endothelial cells.

Transport of insulin across the microvasculature is necessary to reach its target organs (e.g., adipose and muscle tissues) and is rate limiting in insulin action. Morphological evidence suggests that insulin enters endothelial cells of the microvasculature, and studies with large vessel-derived endothelial cells show insulin uptake; however, little is known about the actual transcytosis of insulin and how this occurs in the relevant microvascular endothelial cells. We report an approach to study insulin transcytosis across individual, primary human adipose microvascular endothelial cells (HAMECs), involving insulin uptake followed by vesicle-mediated exocytosis visualized by total internal reflection fluorescence microscopy. In this setting, fluorophore-conjugated insulin exocytosis depended on its initial binding and uptake, which was saturable and much greater than in muscle cells. Unlike its degradation within muscle cells, insulin was stable within HAMECs and escaped lysosomal colocalization. Insulin transcytosis required dynamin but was unaffected by caveolin-1 knockdown or cholesterol depletion. Instead, insulin transcytosis was significantly inhibited by the clathrin-mediated endocytosis inhibitor Pitstop 2 or siRNA-mediated clathrin depletion. Accordingly, insulin internalized for 1 min in HAMECs colocalized with clathrin far more than with caveolin-1. This study constitutes the first evidence of vesicle-mediated insulin transcytosis and highlights that its initial uptake is clathrin dependent and caveolae independent.