Predicting nodal metastases in squamous cell carcinoma of the oral tongue using artificial intelligence

OBJECTIVE

The presence of occult nodal metastases in patients with squamous cell carcinoma (SCC) of the oral tongue has implications for treatment. Upwards of 30% of patients will have occult nodal metastases, yet a significant number of patients undergo unnecessary neck dissection to confirm nodal status. This study sought to predict the presence of nodal metastases in patients with SCC of the oral tongue using a convolutional neural network (CNN) that analyzed visual histopathology from the primary tumor alone.

METHODS

Cases of SCC of the oral tongue were identified from the records of a single institution. Only patients with complete pathology data were included in the study. The primary tumors were randomized into 2 groups for training and testing, which was performed at 2 different levels of supervision. Board-certified pathologists annotated each slide. HALO-AI convolutional neural network and image software was used to perform training and testing. Receiver operator characteristic (ROC) curves and the Youden J statistic were used for primary analysis.

RESULTS

Eighty-nine cases of SCC of the oral tongue were included in the study. The best performing algorithm had a high level of supervision and a sensitivity of 65% and specificity of 86% when identifying nodal metastases. The area under the curve (AUC) of the ROC curve for this algorithm was 0.729.

CONCLUSION

A CNN can produce an algorithm that is able to predict nodal metastases in patients with squamous cell carcinoma of the oral tongue by analyzing the visual histopathology of the primary tumor alone.

Lymph Node Metastases in Papillary Thyroid Carcinoma can be Predicted by a Convolutional Neural Network: a Multi-Institution Study

OBJECTIVES

The presence of nodal metastases in patients with papillary thyroid carcinoma (PTC) has both staging and treatment implications. However, lymph nodes are often not removed during thyroidectomy. Prior work has demonstrated the capability of artificial intelligence (AI) to predict the presence of nodal metastases in PTC based on the primary tumor histopathology alone. This study aimed to replicate these results with multi-institutional data.

METHODS

Cases of conventional PTC were identified from the records of 2 large academic institutions. Only patients with complete pathology data, including at least 3 sampled lymph nodes, were included in the study. Tumors were designated "positive" if they had at least 5 positive lymph node metastases. First, algorithms were trained separately on each institution's data and tested independently on the other institution's data. Then, the data sets were combined and new algorithms were developed and tested. The primary tumors were randomized into 2 groups, one to train the algorithm and another to test it. A low level of supervision was used to train the algorithm. Board-certified pathologists annotated the slides. HALO-AI convolutional neural network and image software was used to perform training and testing. Receiver operator characteristic curves and the Youden J statistic were used for primary analysis.

RESULTS

There were 420 cases used in analyses, 45% of which were negative. The best performing single institution algorithm had an area under the curve (AUC) of 0.64 with a sensitivity and specificity of 65% and 61% respectively, when tested on the other institution's data. The best performing combined institution algorithm had an AUC of 0.84 with a sensitivity and specificity of 68% and 91% respectively.

CONCLUSION

A convolutional neural network can produce an accurate and robust algorithm that is capable of predicting nodal metastases from primary PTC histopathology alone even in the setting of multi-institutional data.

The inflammatory response of human pancreatic cancer samples compared to normal controls

Pancreatic ductal adenocarcinoma (PDAC) is a poor prognosis cancer with an aggressive growth profile that is often diagnosed at late stage and that has few curative or therapeutic options. PDAC growth has been linked to alterations in the pancreas microbiome, which could include the presence of the fungus Malassezia. We used RNA-sequencing to compare 14 matched tumor and normal (tumor adjacent) pancreatic cancer samples and found Malassezia RNA in both the PDAC and normal tissues. Although the presence of Malassezia was not correlated with tumor growth, a set of immune- and inflammatory-related genes were up-regulated in the PDAC compared to the normal samples, suggesting that they are involved in tumor progression. Gene set enrichment analysis suggests that activation of the complement cascade pathway and inflammation could be involved in pro PDAC growth.

G-CSF Is a Novel Mediator of T-Cell Suppression and an Immunotherapeutic Target for Women with Colon Cancer

PURPOSE

G-CSF enhances colon cancer development. This study defines the prevalence and effects of increased G-CSF signaling in human colon cancers and investigates G-CSF inhibition as an immunotherapeutic strategy against metastatic colon cancer.

EXPERIMENTAL DESIGN

Patient samples were used to evaluate G-CSF and G-CSF receptor (G-CSFR) levels by IHC with sera used to measure G-CSF levels. Peripheral blood mononuclear cells were used to assess the rate of G-CSFR+ T cells and IFNγ responses to chronic ex vivo G-CSF. An immunocompetent mouse model of peritoneal metastasis (MC38 cells in C57Bl/6J) was used to determine the effects of G-CSF inhibition (αG-CSF) on survival and the tumor microenvironment (TME) with flow and mass cytometry.

RESULTS

In human colon cancer samples, the levels of G-CSF and G-CSFR are higher compared to normal colon tissues from the same patient. High patient serum G-CSF is associated with increases in markers of poor prognosis, (e.g., VEGF, IL6). Circulating T cells from patients express G-CSFR at double the rate of T cells from controls. Prolonged G-CSF exposure decreases T cell IFNγ production. Treatment with αG-CSF shifts both the adaptive and innate compartments of the TME and increases survival (HR, 0.46; P = 0.0237) and tumor T-cell infiltration, activity, and IFNγ response with greater effects in female mice. There is a negative correlation between serum G-CSF levels and tumor-infiltrating T cells in patient samples from women.

CONCLUSIONS

These findings support G-CSF as an immunotherapeutic target against colon cancer with greater potential benefit in women.

The immune response to a fungus in pancreatic cancer samples

Pancreatic ductal adenocarcinoma (PDAC) is a poor prognosis cancer with an .aggressive growth profile that is often diagnosed at late stage and that has few curative or therapeutic options. PDAC growth has been linked to alterations in the pancreas microbiome, which could include the presence of the fungus Malassezia. We used RNA-sequencing to compare 14 paired tumor and normal (tumor adjacent) pancreatic cancer samples and found Malassezia RNA in both the PDAC and normal tissues. Although the presence of Malassezia was not correlated with tumor growth, a set of immune- and inflammatory-related genes were up-regulated in the PDAC compared to the normal samples, suggesting that they are involved in tumor progression. Gene set enrichment analysis suggests that activation of the complement cascade pathway and inflammation could be involved in pro PDAC growth.

Ulcerative Colitis: Novel Epithelial Insights Provided by Single Cell RNA Sequencing

Ulcerative Colitis (UC) is a chronic inflammatory disease of the intestinal tract for which a definitive etiology is yet unknown. Both genetic and environmental factors have been implicated in the development of UC. Recently, single cell RNA sequencing (scRNA-seq) technology revealed cell subpopulations contributing to the pathogenesis of UC and brought new insight into the pathways that connect genome to pathology. This review describes key scRNA-seq findings in two major studies by Broad Institute and University of Oxford, investigating the transcriptomic landscape of epithelial cells in UC. We focus on five major findings: (1) the identification of BEST4 + cells, (2) colonic microfold (M) cells, (3) detailed comparison of the transcriptomes of goblet cells, and (4) colonocytes and (5) stem cells in health and disease. In analyzing the two studies, we identify the commonalities and differences in methodologies, results, and conclusions, offering possible explanations, and validated several cell cluster markers. In systematizing the results, we hope to offer a framework that the broad scientific GI community and GI clinicians can use to replicate or corroborate the extensive new findings that RNA-seq offers.

Predicting nodal metastases in papillary thyroid carcinoma using artificial intelligence

BACKGROUND

The presence of nodal metastases is important in the treatment of papillary thyroid carcinoma (PTC). We present our experience using a convolutional neural network (CNN) to predict the presence of nodal metastases in a series of PTC patients using visual histopathology from the primary tumor alone.

METHODS

174 cases of PTC were evaluated for the presence or absence of lymph metastases. The artificial intelligence (AI) algorithm was trained and tested on its ability to discern between the two groups.

RESULTS

The best performing AI algorithm demonstrated a sensitivity and specificity of 94% and 100%, respectively, when identifying nodal metastases.

CONCLUSION

A CNN can be used to accurately predict the likelihood of nodal metastases in PTC using visual data from the primary tumor alone.

A Deep Learning Convolutional Neural Network Can Differentiate Between Helicobacter Pylori Gastritis and Autoimmune Gastritis With Results Comparable to Gastrointestinal Pathologists

CONTEXT.—

Pathology studies using convolutional neural networks (CNNs) have focused on neoplasms, while studies in inflammatory pathology are rare. We previously demonstrated a CNN differentiates reactive gastropathy, Helicobacter pylori gastritis (HPG), and normal gastric mucosa.

OBJECTIVE.—

To determine whether a CNN can differentiate the following 2 gastric inflammatory patterns: autoimmune gastritis (AG) and HPG.

DESIGN.—

Gold standard diagnoses were blindly established by 2 gastrointestinal (GI) pathologists. One hundred eighty-seven cases were scanned for analysis by HALO-AI. All levels and tissue fragments per slide were included for analysis. The cases were randomized, 112 (60%; 60 HPG, 52 AG) in the training set and 75 (40%; 40 HPG, 35 AG) in the test set. A HALO-AI correct area distribution (AD) cutoff of 50% or more was required to credit the CNN with the correct diagnosis. The test set was blindly reviewed by pathologists with different levels of GI pathology expertise as follows: 2 GI pathologists, 2 general surgical pathologists, and 2 residents. Each pathologist rendered their preferred diagnosis, HPG or AG.

RESULTS.—

At the HALO-AI AD percentage cutoff of 50% or more, the CNN results were 100% concordant with the gold standard diagnoses. On average, autoimmune gastritis cases had 84.7% HALO-AI autoimmune gastritis AD and HP cases had 87.3% HALO-AI HP AD. The GI pathologists, general anatomic pathologists, and residents were on average, 100%, 86%, and 57% concordant with the gold standard diagnoses, respectively.

CONCLUSIONS.—

A CNN can distinguish between cases of HPG and autoimmune gastritis with accuracy equal to GI pathologists.

Comparing Deep Learning and Immunohistochemistry in Determining the Site of Origin for Well-Differentiated Neuroendocrine Tumors

Background

Determining the site of origin for metastatic well-differentiated neuroendocrine tumors (WDNETs) is challenging, and immunohistochemical (IHC) profiles do not always lead to a definitive diagnosis. We sought to determine if a deep-learning convolutional neural network (CNN) could improve upon established IHC profiles in predicting the site of origin in a cohort of WDNETs from the common primary sites.

Materials and Methods

Hematoxylin and eosin (H&E)-stained tissue microarrays (TMAs) were created using 215 WDNETs arising from the known primary sites. A CNN trained and tested on 60% (n = 130) and 40% (n = 85) of these cases, respectively. One hundred and seventy-nine cases had TMA tissue remaining for the IHC analysis. These cases were stained with IHC markers pPAX8, CDX2, SATB2, and thyroid transcription factor-1 (markers of pancreas/duodenum, ileum/jejunum/duodenum, colorectum/appendix, and lung WDNET sites of origin, respectively). The CNN diagnosis was deemed correct if it designated a majority or plurality of the tumor area as the known site of origin. The IHC diagnosis was deemed correct if the most specific marker for a particular site of origin met an H-score threshold determined by two pathologists.

Results

When all cases were considered, the CNN correctly identified the site of origin at a lower rate compared to IHC (72% vs. 82%, respectively). Of the 85 cases in the CNN test set, 66 had sufficient TMA material for IHC stains, thus 66 cases were available for a direct case-by-case comparison of IHC versus CNN. The CNN correctly identified 70% of these cases, while IHC correctly identified 76%, a finding that was not statistically significant (P = 0.56).

Conclusion

A CNN can identify WDNET site of origin at an accuracy rate close to the current gold standard IHC methods.

The MK2 pathway is linked to G-CSF, cytokine production and metastasis in gastric cancer: a novel intercorrelation analysis approach

Background

Gastric cancer is associated with chronic inflammation, but there is still much to understand about the tumor microenvironment and the underlying tumor-promoting mechanisms. The Map kinase-activated protein kinase 2 (MK2) pathway is a regulator of inflammatory cytokine production that we have been studying in gastrointestinal cancers. Here, we set out to determine the significance of this gene in gastric cancer along with its downstream mediators and if there were differences in the primary tumors with and without metastasis.

Methods

Human gastric cancer tissues with and without metastasis were examined for MK2 expression and cytokine profile in organ culture supernatants. Advanced statistical methods including a lower triangular correlation matrix, novel rooted correlation network, linear and logistic regression modeling along with Kruskal–Wallis testing with Sidak correction for multiple testing were applied to gain understanding of cytokines/chemokines linked to metastasis.

Results

The MK2 pathway is strongly linked with metastasis and a panel of cytokines. Gene expression was able to classify gastric cancer metastasis 85.7% of the time. A significant association with a panel of cytokines was found, including G-CSF, GM-CSF, Mip-1β, IFN-α, MCP-1, IL-1β, IL-6, and TNF-α. Mip-1β was found to have the strongest association with MK2 and metastasis after Sidak correction for multiple testing.

Conclusions

MK2 gene expression and a novel associated cytokine panel are linked to gastric cancer metastasis. G-CSF is the strongest cytokine to differentiate between metastasis and non-metastasis patients and had the lowest P value, while Mip-1β showed the strongest association with MK2 and metastasis after Sidak correction. MK2 and associated cytokines are potential biomarkers for gastric cancer metastasis. The novel intercorrelation analysis approach is a promising method for understanding the complex nature of cytokine/chemokine regulation and links to disease outcome.

A Deep Learning Convolutional Neural Network Can Recognize Common Patterns of Injury in Gastric Pathology

CONTEXT.—

Most deep learning (DL) studies have focused on neoplastic pathology, with the realm of inflammatory pathology remaining largely untouched.

OBJECTIVE.—

To investigate the use of DL for nonneoplastic gastric biopsies.

DESIGN.—

Gold standard diagnoses were blindly established by 2 gastrointestinal pathologists. For phase 1, 300 classic cases (100 normal, 100 Helicobacter pylori, 100 reactive gastropathy) that best displayed the desired pathology were scanned and annotated for DL analysis. A total of 70% of the cases for each group were selected for the training set, and 30% were included in the test set. The software assigned colored labels to the test biopsies, which corresponded to the area of the tissue assigned a diagnosis by the DL algorithm, termed area distribution (AD). For Phase 2, an additional 106 consecutive nonclassical gastric biopsies from our archives were tested in the same fashion.

RESULTS.—

For Phase 1, receiver operating curves showed near perfect agreement with the gold standard diagnoses at an AD percentage cutoff of 50% for normal (area under the curve [AUC] = 99.7%) and H pylori (AUC = 100%), and 40% for reactive gastropathy (AUC = 99.9%). Sensitivity/specificity pairings were as follows: normal (96.7%, 86.7%), H pylori (100%, 98.3%), and reactive gastropathy (96.7%, 96.7%). For phase 2, receiver operating curves were slightly less discriminatory, with optimal AD cutoffs reduced to 40% across diagnostic groups. The AUCs were 91.9% for normal, 100% for H pylori, and 94.0% for reactive gastropathy. Sensitivity/specificity parings were as follows: normal (73.7%, 79.6%), H pylori (95.7%, 100%), reactive gastropathy (100%, 62.5%).

CONCLUSIONS.—

A convolutional neural network can serve as an effective screening tool/diagnostic aid for H pylori gastritis.

SATB2 Versus CDX2: A Battle Royale for Diagnostic Supremacy in Mucinous Tumors

CONTEXT.—

Metastatic mucinous tumors present a diagnostic challenge for pathologists as tumor histomorphology is often nonspecific and optimal immunoprofiles are still under investigation.

OBJECTIVE.—

To present a head-to-head comparison of special AT-rich sequence-binding protein 2 (SATB2) and caudal type homeobox 2 (CDX2) expression in a diverse array of primary mucinous tumors.

DESIGN.—

SATB2 and CDX2 immunohistochemical stains were performed on whole sections from 44 mucinous colorectal carcinomas and 175 noncolorectal mucinous tumors. A nuclear scoring system measuring intensity (0-3+) and percentage staining (0 = <5%, 1 = 5%-49%, 2 = ≥50%) was implemented, producing an additive histologic score (H-score).

RESULTS.—

SATB2 demonstrated acceptable accuracy at low to moderate expression levels (H-scores of 1-4). With these H-score cutoffs, overall accuracy was greater than 90%. In contrast, CDX2's accuracy rivaled that of SATB2 only at an H-score of 5 (89.0%), as its specificity suffered at lower expression levels (<70.0% at H-scores of 1-4). Using a moderate H-score cutoff of 3 or higher, significant differences for both sensitivity and specificity were identified between SATB2 and CDX2 (P = .01 for sensitivity and P < .001 for specificity), though these stains were near equivalent when each was interpreted as positive at its respective optimal H-score (SATB2 ≥ 3 and CDX2 = 5).

CONCLUSIONS.—

SATB2 is a more accurate marker of colorectal origin across a variety of expression levels compared with CDX2 when applied to mucinous tumors from a host of primary sites. However, these stains are near equivalent when each is interpreted at its optimal expression level.

SATB2 Versus CDX2: A Battle Royale for Diagnostic Supremacy in Mucinous Tumors

CONTEXT.—

Metastatic mucinous tumors present a diagnostic challenge for pathologists as tumor histomorphology is often nonspecific and optimal immunoprofiles are still under investigation.

OBJECTIVE.—

To present a head-to-head comparison of special AT-rich sequence-binding protein 2 (SATB2) and caudal type homeobox 2 (CDX2) expression in a diverse array of primary mucinous tumors.

DESIGN.—

SATB2 and CDX2 immunohistochemical stains were performed on whole sections from 44 mucinous colorectal carcinomas and 175 noncolorectal mucinous tumors. A nuclear scoring system measuring intensity (0-3+) and percentage staining (0 = <5%, 1 = 5%-49%, 2 = ≥50%) was implemented, producing an additive histologic score (H-score).

RESULTS.—

SATB2 demonstrated acceptable accuracy at low to moderate expression levels (H-scores of 1-4). With these H-score cutoffs, overall accuracy was greater than 90%. In contrast, CDX2's accuracy rivaled that of SATB2 only at an H-score of 5 (89.0%), as its specificity suffered at lower expression levels (<70.0% at H-scores of 1-4). Using a moderate H-score cutoff of 3 or higher, significant differences for both sensitivity and specificity were identified between SATB2 and CDX2 (P = .01 for sensitivity and P < .001 for specificity), though these stains were near equivalent when each was interpreted as positive at its respective optimal H-score (SATB2 ≥ 3 and CDX2 = 5).

CONCLUSIONS.—

SATB2 is a more accurate marker of colorectal origin across a variety of expression levels compared with CDX2 when applied to mucinous tumors from a host of primary sites. However, these stains are near equivalent when each is interpreted at its optimal expression level.

Gross Pathology of Routine Pediatric Tonsillectomy Specimens: Optimizing the Value of Patient Care

Objective

This investigation seeks to evaluate the effect of gross pathologic analysis on our management of patients undergoing routine tonsillectomy and to evaluate charges and reimbursement.

Study Design

Retrospective chart review from 2005 through 2016.

Setting

Academic medical center.

Subjects and Methods

Participants were pediatric patients aged 14 years and younger undergoing tonsillectomy for either sleep-disordered breathing or tonsillitis, with tonsillectomy specimens evaluated by pathology, and without any risk factors for pediatric malignancy. Records were reviewed for demographics, surgical indications, and pathology. Abnormal reports prompted an in-depth review of the chart. Charges and reimbursement related to both hospital and professional fees for gross tonsil analysis were evaluated.

Results

From 2005 to 2016, 3183 routine pediatric tonsillectomy cases were performed with corresponding specimens that were sent for gross analysis revealing no significant pathologic findings; 1841 were males and 1342 were females. Ten cases underwent microscopy by pathologist order, revealing normal tonsillar tissue. The mean charge per patient for gross analysis was $60.67 if tonsils were together as 1 specimen and $77.67 if tonsils were sent as 2 separate specimens; respective reimbursement amounts were $28.74 and $35.90.

Conclusions

Gross pathologic analysis did not change our management of routine pediatric tonsillectomy patients. Foregoing the practice at our institution would eliminate $19,171.72 to $24,543.72 in charges and $9081.40 to $11,344.40 in reimbursement per year. Eliminating this test would improve the value of patient care by saving health care resources without compromising clinical outcomes.

Upregulation of P2Y2R, Active uPA, and PAI-1 Are Essential Components of Hantavirus Cardiopulmonary Syndrome

Sin Nombre virus (SNV) causes hantavirus cardiopulmonary pulmonary syndrome (HCPS) with the loss of pulmonary vascular endothelial integrity, and pulmonary edema without causing cytopathic effects on the vascular endothelium. HCPS is associated primarily with a dysregulated immune response. We previously found occult signs of hemostatic imbalance in the form of a sharp >30-100 fold increase in the expression of plasminogen activator inhibitor type 1 (PAI-1), in serial blood plasma draws of terminal stage-patients. However, the mechanism of the increase in PAI-1 remains unclear. PAI-1 is a primary inhibitor of fibrinolysis caused by tissue plasminogen activator (tPA) and urokinase plasminogen activator plasma (uPA). Here, we investigate factors that contribute to PAI-1 upregulation during HCPS. Using zymography, we found evidence of PAI-1-refractory uPA activity and no tPA activity in plasma samples drawn from HCPS patients. The sole prevalence of uPA activity suggested that severe inflammation drove PAI-1 activity. We have recently reported that the P2Y₂ receptor (P2Y₂R) mediates SNV infectivity by interacting in cis with β₃ integrins, which activates the latter during infection. P2Y₂R is a known effector for several biological processes relevant to HCPS pathogenesis, such as upregulation of tissue factor (TF), a primary initiator of the coagulation cascade, stimulating vascular permeability and leukocyte homing to sites of infection. As P2Y₂R is prone to upregulation under conditions of inflammation, we compared the expression level of P2Y₂R in formalin fixed tissues of HCPS decedents using a TaqMan assay and immunohistochemistry. Our TaqMan results show that the expression of P2Y₂R is upregulated significantly in HCPS cases compared to non- HCPS controls (P < 0.001). Immunohistochemistry showed that lung macrophages were the primary reservoir of high and coincident localization of P2Y₂R, uPA, PAI-1, and TF antigens. We also observed increased staining for SNV antigens in the same tissue segments where P2Y₂R expression was upregulated. Conversely, sections of low P2Y₂R expression showed weak manifestations of macrophages, SNV, PAI-1, and TF. Coincident localization of P2Y₂R and PAI-1 on macrophage deposits suggests an inflammation-dependent mechanism of increasing pro-coagulant activity in HCPS in the absence of tissue injury.

High levels of tumor-associated neutrophils are associated with improved overall survival in patients with stage II colorectal cancer

Conflicting reports regarding whether high tumor-associated neutrophils (TAN) are associated with outcomes in colorectal cancer (CRC) exist. Previous investigators have counted TAN using non-neutrophil-specific immunohistochemistry (IHC) stains. We examined whether TAN levels as determined by multi-field manual counting would predict prognosis. IRB approval was obtained and two pathologists, blinded to stage/outcome, counted TAN in 20 high power fields (HPF) per specimen. TAN score was defined as the mean of these counts. High TAN was defined as at or greater than the median score for that stage. Demographics, tumor characteristics, and overall survival (OS) were obtained from the records and examined for association with TAN score. IHC for arginase expression was performed in a subset of samples. 221 patients were included. Stage II patients with high TAN scores had an OS of 232 months as compared to those with low TAN (OS = 85 months, p = 0.03). The survival benefit persisted in multivariable analysis (HR 0.48, CI 0.25-0.91, p = 0.026) controlling for age and sex. Women had increased survival as compared to men, and there were no significant prognostic associations with TAN count in stage III/IV patients, although there were only 12 stage IV patients. Arginase staining did not provide additional information. Stage II colorectal cancer patients with high TAN live nearly 3 times longer than those with low TAN. Women with stage II disease and high TAN counts appear to be driving the survival benefit seen in the stage II patients and have increased overall survival in all stages.

Phase II Trial Using a Combination of Oxaliplatin, Capecitabine, and Celecoxib with Concurrent Radiation for Newly Diagnosed Resectable Rectal Cancer

LESSONS LEARNED

Colorectal cancers exhibit a high level of cyclooxygenase-2 (COX-2) expression with strong preclinical rationale for improved clinical outcomes with COX-2 inhibition. Celecoxib is a COX-2 inhibitor and we have shown that it can be safely combined with capecitabine and oxaliplatin as part of neoadjuvant treatment with radiation therapy (RT) in rectal cancer.There was a significant improvement in skin toxicity with this combination as compared with historical data. Considering the field has moved on to single-agent capecitabine, we believe future trials with capecitabine and celecoxib hold potential.

BACKGROUND

Improved survival is seen among patients with rectal cancer who achieve pathologic complete response (pCR) after neoadjuvant therapy. Cyclooxygenase-2 (COX-2) expression is increased in gastrointestinal malignancies and it may serve as a target to enhance pathologic response. A trial combining chemoradiation and COX-2 inhibition was conducted to evaluate the pCR rate, surgical outcomes, survival, and treatment toxicity.

METHODS

Patients with resectable (T3-4, N1-2) rectal cancer within 12 cm of the anal verge were included in this phase II clinical trial. The neoadjuvant treatment consisted of capecitabine 850 mg/m² b.i.d. Monday through Friday for 5 weeks, weekly oxaliplatin 50 mg/m² intravenous (IV), celecoxib 200 mg b.i.d. daily, along with concurrent 45 gray radiation therapy in 25 fractions.

RESULTS

Thirty-two patients were included in the final analysis. The primary endpoint was pCR: 31% (95% confidence interval [CI]: 16%-50%). Secondary endpoints were surgical downstaging (SD): 75% (95% CI: 57%-89%) and sphincter-sparing surgery (SSS): 56% (95% CI: 38%-74%). Common grade >3 toxicities were diarrhea and abnormal liver function tests (9% each). Grade 0 and 1 toxicities included radiation dermatitis (59% and 34%, respectively) and proctitis (63% and 28%, respectively). At 3 years, disease-free survival and overall survival (OS) were 84% (95% CI: 65%-93%) and 94% (95% CI: 77%-98%), respectively.

CONCLUSION

Chemoradiation with celecoxib in rectal cancer was well tolerated and demonstrated high rates of pCR, SD, and SSS. Improvement in skin toxicity (34% grade 1 and no grade 3/4) as compared with historical results (43%-78% grade 3/4) seems to be a significant improvement with addition of celecoxib to neoadjuvant chemotherapy.

Navajo Neurohepatopathy : A Case Report and Literature Review Emphasizing Clinicopathologic Diagnosis

Navajo Neurohepatopathy (NNH) is a rare hepatocerebral mitochondrial DNA (mtDNA) depletion syndrome (MDS) with nonspecific clinical or pathologic features aside from Navajo ancestry. Because of the rarity of NNH, diagnosis rests on close clinicopathologic correlation and appropriate tissue triage for quantitative mtDNA analysis. We present a new case of NNH in which the clinical presentation and H&E liver biopsy histology indicated the need for NNH workup. Quantitative analysis of mtDNA in liver tissue was significantly reduced, and mutational analysis of the MPV17 gene confirmed homozygosity for the NNH-associated missense mutation, R50Q. The patient is now one year post liver transplant and continues to have normal liver function tests but suffers multiple immunosuppression-associated co-morbidities. A comprehensive literature review is provided to assist in diagnosis and management of NNH. (Acta gastroenterol. belg., 2016, 79, 463-469).

Blockade of MK2 is protective in inflammation-associated colorectal cancer development

Chronic inflammation is a risk factor for colorectal cancer. The MAPK-activated protein kinase 2 (MK2) pathway controls multiple cellular processes including p38-dependent inflammation. This is the first study to investigate the role of MK2 in development of colitis-associated colon cancer (CAC). Herein, we demonstrate that MK2(-/-) mice are highly resistant to neoplasm development when exposed to AOM/DSS, while wild type (WT) C57BL/6 develop multiple neoplasms with the same treatment. MK2-specific cytokines IL-1, IL-6 and TNF-α were substantially decreased in AOM/DSS treated MK2(-/-) mouse colon tissues compared with WT mice, which coincided with a marked decrease in macrophage influx. Restoring MK2-competent macrophages by injecting WT bone marrow derived macrophages into MK2(-/-) mice led to partial restoration of inflammatory cytokine production with AOM/DSS treatment; however, macrophages were not sufficient to induce neoplasm development. These results indicate that MK2 functions as an inflammatory regulator to promote colonic neoplasm development and may be a potential target for CAC.

Diffuse glutamine synthetase overexpression restricted to areas of peliosis in a β-catenin-activated hepatocellular adenoma: a potential pitfall in glutamine synthetase interpretation

Hepatocellular adenomas have recently been classified into four subtypes based on molecular findings: hepatocyte nuclear factor 1α (HNF1α) inactivated, inflammatory/telangiectatic, β-catenin activated, and unclassifiable. β-catenin-activated adenomas have the potential for malignant transformation and are thus important to recognize. Diffuse glutamine synthetase immunohistochemical positivity has been shown to be a reliable surrogate marker for β-catenin activation, though variations in staining patterns may be difficult to interpret. We report a case of a peliotic adenoma that was morphologically consistent with a β-catenin wild-type hepatocellular adenoma but harbored a β-catenin mutation by molecular analysis. The tumor lacked nuclear β-catenin positivity and demonstrated a hitherto undescribed pattern of glutamine synthetase overexpression restricted to areas of peliosis with mostly negative staining in non-peliotic areas. This pattern was initially interpreted as physiologic and may represent a potential pitfall in glutamine synthetase interpretation.

Is ovarian and adrenal venous catheterization and sampling helpful in the investigation of hyperandrogenic women?

OBJECTIVE

To audit our practice of performing ovarian and adrenal venous catheterization and sampling in hyperandrogenic women who fail to suppress their elevated androgen levels following a 48-h low-dose dexamethasone suppression test (LDDST). We considered the technical success rate of catheterization, the extra information obtained in addition to the standard biochemical tests and imaging findings, and the impact of sampling on management decisions.

DESIGN

A retrospective analysis of the results of all ovarian and adrenal venous catheterizations performed at St Bartholomew's Hospital, London, in the years 1980-1996.

PATIENTS AND METHODS

Baseline ovarian and adrenal androgens were measured in all women presenting with symptoms and signs of hyperandrogenism. Those patients who failed to suppress their elevated testosterone (T), androstenedione (A4) and/or dehydroepiandrosterone-sulphate (DHEAS) levels following a LDDST to within the normal range or to less than 50% of the baseline value were investigated further with adrenal computed tomography (CT), ovarian ultrasound, and ovarian and adrenal venous catheterization and sampling.

RESULTS

Results were available in 38 patients. The overall catheterization success rate was: all four veins in 27%, three veins in 65%, two veins in 87%. The success rate for each individual vein was: right adrenal vein (RAV) 50%, right ovarian vein (ROV) 42%, left adrenal vein (LAV) 87% and left ovarian vein (LOV) 73%. Eight patients were found to have tumours by means of imaging (adrenal CT and ovarian ultrasound), three adrenal and five ovarian, seven of which underwent operation. In six of these patients the clinical presentation was suggestive of the presence of a tumour; in addition, the combination of imaging findings allowed the detection of suspicious adrenal and ovarian masses in all eight cases. The five patients with ovarian tumours had serum testosterone levels > 4.5 nmol/l. In a further eight patients, laparotomy was performed based on a combination of diagnostic and therapeutic indications; in two of these patients the catheterization results were suggestive of an ovarian tumour. All these eight patients were shown histologically to have polycystic ovarian syndrome (PCOS), and no occult ovarian tumour was identified. None of the patients with nontumourous hyperandrogenism had a baseline testosterone level in excess of 7 nmol/l (median 4.4 nmol/l, range 2.5-7 nmol/l).

CONCLUSIONS

Our results suggest that ovarian and adrenal venous catheterization and sampling should not be performed routinely in women presenting with symptoms and signs of hyperandrogenism, even if they fail to suppress their elevated androgen levels to a formal 48-h LDDST. All patients presenting with symptoms and signs of hyperandrogenism and elevated androgen levels, and where the suspicion of an androgen-secreting tumour is high, should have adrenal CT and ovarian ultrasound imaging to detect such a tumour. Venous catheterization and sampling should be reserved for patients in whom uncertainty remains, as the presence of a small ovarian tumour cannot be excluded on biochemical and imaging studies used in this series alone. Its use should be restricted to units with expertise in this area.

In vivo staphylococcal superantigen-driven polyclonal Ig responses in mice: dependence upon CD4(+) cells and human MHC class II

Staphylococcal enterotoxin (SE) B and seven other staphylococcal superantigens (SAg), despite promoting vigorous Ig production in human peripheral blood mononuclear cell cultures, are exceedingly poor at eliciting Ig responses in cultures of spleen cells from C57BL/10J (B10) or C3H/HeJ mice. In contrast, SEB elicits Ig responses in cultures of spleen cells from human MHC class II-transgenic mice. Whereas i.p. administration of SEB (0.2-20 microg) to non-transgenic B10 mice elicits very weak in vivo Ig responses, identical treatment of CD4(+) cell-intact (but not CD4(+) cell-depleted) human MHC class II-transgenic mice elicits dramatic increases in both splenic Ig-secreting cells and serum Ig levels. Over a 2-week period, the SEB-induced in vivo Ig responses peak and then plateau or fall in association with a preferential increase in splenic CD8(+) cells. Nevertheless, in vivo depletion of CD8(+) cells has no sustained effect on SEB-driven Ig responses. Taken together, these observations demonstrate that the effects of SAg on in vivo humoral immune responses are highly CD4(+) cell dependent, are substantially CD8(+) cell independent and can be successfully investigated using human MHC class II-transgenic mice. This model system may be useful in investigating the polyclonally activating effects of microbial products (prototypic environmental insults) on the development of systemic autoimmunity.

Ultrasonographic appearance of splenic disease in 101 cats

The sonographic findings in 101 cats with splenic abnormalities are presented. Diagnosis was made by ultrasound-guided fine needle aspirate or fine-needle biopsy (n = 91), ultrasound-guided core biopsy (n = 1), surgical core biopsy (n = 1), or necropsy (n = 10). Two cats had more than one diagnostic procedure (fine needle aspirate and necropsy or core biopsy and necropsy). The splenic abnormalities included lymphosarcoma (n = 30), mast cell tumor (n = 27), extramedullary hematopoiesis and/or lymphoid hyperplasia (n = 27), epithelial tumors (n = 6), mesenchymal tumors (n = 4), malignant histiocytosis (n = 2), myeloproliferative disease (n = 2), pyogranulomatous inflammation (n = 2), erythroleukemia (n = 1), eosinophilic syndrome (n = 1), hematoma (n = 1), and granulomatous splenitis (n = 1). Three cats had more than one splenic abnormality (mast cell tumor and metastatic carcinoma, pyogranulomatous inflammation and lymphoid hyperplasia, histiocytic lymphosarcoma, and lymphoid hyperplasia). Pathognomonic changes were not seen for any of the diseases.

Analysis of dynamic cohort data

Left-truncated and interval-censored data, termed dynamic cohort data, arise in longitudinal studies with rolling admissions and only occasional follow-up. The authors compared four approaches for analyzing such data: a constant hazard model; maximum likelihood estimation with flexible parametric models; the midpoint method, in which the midpoint of the last negative and first positive test result is used in a Cox proportional hazards model that accounts for left truncation; and a semiparametric method that uses imputed failure times in the Cox model. By using a simulation study, they assessed the performance of these approaches under conditions that can arise in observational studies: changes in disease incidence and changes in the underlying population. The simulation results indicated that the constant hazard model and midpoint method were inadequate and that the flexible parametric model was useful when enough parameters were used in modeling the baseline hazard. The semiparametric method ensured correct parameter (odds ratio) estimation when the baseline hazard was misspecified, but the trade-off increased computational complexity. In this paper, a study of the incidence of human immunodeficiency virus in patients repeatedly tested for the virus at a sexually transmitted disease clinic in New Orleans, Louisiana, illustrates the methods used.

Hepatitis C antibody status and outcomes in renal transplant recipients

BACKGROUND

Hepatitis occurs frequently in patients with end-stage renal disease. In 1997, 0.7% of patients receiving a renal transplant were positive for hepatitis C antibodies. Concern has been raised as to whether these patients are at an increased mortality risk after renal transplantation compared with patients who are hepatitis C antibody negative. To help answer this question, we analyzed data from the United States Renal Data System from October of 1988 through June of 1998.

METHODS

Primary study endpoints were patient death and death censored graft loss. Secondary study endpoints included cardiovascular, infectious, malignant, and infection-related death. Kaplan-Meier survival estimates as well as Cox proportional hazard models were used to evaluate the impact of hepatitis C antibody status on the study endpoints.

RESULTS

A total of 73,707 patients were analyzed. Patient survival by Kaplan-Meier analysis was higher in hepatitis C-positive patients, whereas death censored graft survival trended lower in the very long term. By the Cox model, hepatitis C-positive adjusted patient survival is slightly superior to that of hepatitis C-negative patients.

CONCLUSIONS

Renal transplant recipients who are hepatitis C antibody positive do not have an increased risk of death after transplantation compared with hepatitis C-negative recipients. The current policy of transplanting hepatitis C-positive patients without active liver disease seems to incur no excess mortality risk.

Exponentially increased risk of infectious death in older renal transplant recipients

BACKGROUND

The benefit of renal transplantation for patients with end-stage renal disease (ESRD) has been well documented. This benefit is seen throughout all age ranges of patients. However, it has been documented that older renal transplant recipients are at increased risk for death because of infectious causes when compared with younger recipients. The present study addresses whether this increased risk merely parallels an age-related increase in infectious mortality or is reflective of a particular vulnerability in older renal transplant recipients.

METHODS

Patients wait-listed and transplanted between 1988 and 1997 were analyzed utilizing the United States Renal Data System (USRDS) database. The primary study end point was patient death secondary to infection. Secondary end points included death secondary to cardiovascular cause and malignancy. Cox-proportional hazard models were utilized with all pertinent variables.

RESULTS

Death related to infectious cause increased exponentially in transplanted patients with increasing age (slope = 2.90.34x), while it increased linearly (slope = 1.9x + 8.6) with increasing age for those patients on the waiting list. Overall mortality increases with age were equal between the wait-listed and transplanted groups.

CONCLUSIONS

The overall survival benefit of transplantation is maintained in the older age groups. However, renal transplantation is associated with an increased risk for infectious death beyond the expected age-related increased risk in patients on the renal transplant waiting list. This may have an impact on future immunosuppressive regimens in this population.

Interaction of mycophenolate mofetil and HLA matching on renal allograft survival

INTRODUCTION

The importance of HLA matching for renal transplantation outcomes has been appreciated for several decades. It has been hypothesized that as pharmacologic immunosuppression becomes stronger and more specific, the impact of HLA matching may be vanishing. Mycophenolate Mofetil (MMF) has been demonstrated to both decrease acute rejection and improve three-year graft survival. It is possible that with new immunosuppressive regimens containing MMF the relative effect of HLA matching may be altered. To determine the relative impact of HLA matching in patients on MMF we undertook an analysis of the United States Renal Transplant Data Registry (USRDS).

METHODS

All primary, solitary renal transplants registered at the USRDS between January 1995 and June 1997, on initial immunosuppression that included either MMF or AZA were followed until June 1998. Primary study end points were graft and patient survival. Kaplan-Meier analysis was performed to compare AZA vs. MMF treated patients by HLA mismatch. Cox proportional hazard models were used to investigate the interaction between HLA mismatch and AZA versus MMF therapy on the study endpoints. All multivariate analyses were corrected for 13 potential confounding pretransplant variables including intention to treat immunosuppression.

RESULTS

A total of 19,675 patients were analyzed (8,459 on MMF and 11,216 on AZA). Overall three year graft survival was higher in the MMF group when compared to the AZA group (87% vs. 84% respectively P<0.001). For both AZA and MMF three-year graft survival improved with fewer HLA donor-recipient mismatches. Comparing zero antigen mismatches to six antigen mismatches, the relative improvement was comparable for both patients on AZA (92.4% vs. 80.6%) and MMF (95.2% vs. 82.9%). By Cox proportional hazard model the relative risk for graft loss decreased significantly in both the AZA and MMF treated patients with increased HLA matching.

CONCLUSION

The use of MMF does not obviate the benefits of HLA matching, while HLA matching does not minimize the benefits of MMF on long term graft survival. Our study would suggest that HLA matching and MMF therapy are additive factors in decreasing the risk for renal allograft loss.

Gender differences in the risk for chronic renal allograft failure

BACKGROUND

Despite the known differences in immunological reactivity between males and females, no differences in graft survival have been described among renal transplant recipients with regard to gender. To address this paradox, we analyzed data from 73,477 primary renal transplants collected in the US Renal Data System database.

METHODS

Logistic regression and Cox proportional hazard models were used to investigate the primary study end points, graft loss secondary to acute rejection (AR) or chronic allograft failure (CAF). CAF was defined as graft loss beyond 6 months, not attributable to death, recurrent disease, acute rejection, thrombosis, infection, noncompliance, or technical problems. The models adjusted for 15 covariates including immunosuppressive regimen, and donor and recipient characteristics.

RESULTS

The overall 8-year graft and patient survivals were significantly better in female renal transplant recipients compared with male recipients. However graft survival censored for death was not significantly different by gender. By multivariate analysis, females had a 10% increased odds of AR (OR=1.10, CI 1.02-1.12), but conversely a 10% lower risk of graft loss secondary to CAF (RR=0.9, CI 0.85-0.96). The risk for CAF increased significantly with increasing age for both males and females, but this effect was greater for males than for females (P<0.001).

CONCLUSION

Although female renal transplant recipients have a similar death censored graft survival compared with males, there are important differences in immunological behavior. Females have a higher risk of AR while having a decreased risk of graft loss secondary to CAF.

The impact of simultaneous pancreas-kidney transplantation on long-term patient survival

BACKGROUND

Simultaneous pancreas-kidney transplantation (SPK) ameliorates the progression of microvascular diabetic complications but the procedure is associated with excess initial morbidity and an uncertain effect on patient survival when compared with solitary cadaveric or living donor renal transplantation. We evaluated mortality risks associated with SPK, solitary renal transplantation, and dialysis treatment in a national cohort of type 1 diabetics with end-stage nephropathy.

METHODS

A total of 13,467 adult-type 1 diabetics enrolled on the renal and renal-pancreas transplant waiting list between 10/01/88 and 06/30/97 were followed until 06/30/98. Time-dependent mortality risks and life expectancy were calculated according to the treatment received subsequent to wait-list registration: SPK; cadaveric kidney only (CAD); living donor kidney only (LKD) transplantation; and dialysis [wait-listed, maintenance dialysis treatment (WLD)].

RESULTS

Adjusted 10-year patient survival was 67% for SPK vs. 65% for LKD recipients (P=0.19) and 46% for CAD recipients (P<0.001). The excess initial mortality normally associated with renal transplantation and the risk of early infectious death was 2-fold higher in SPK recipients. The time to achieve equal proportion of survivors as the WLD patients was 170, 95, and 72 days for SPK, CAD, and LKD recipients, respectively (P<0.001). However, the adjusted 5-year morality risk (RR) using WLD as the reference and the expected remaining life years were 0.40, 0.45, and 0.75 and 23.4, 20.9, and 12.6 years for SPK, LKD, and CAD, respectively. There was no survival benefit in SPK recipients > or =50 years old (RR=1.38, P=0.81).

CONCLUSIONS

Among patients with type 1 DM with end-stage nephropathy, SPK transplantation before the age of 50 years was associated with long-term improvement in survival compared to solitary cadaveric renal transplantation or dialysis.

CT assessment of tumour response to treatment: comparison of linear, cross-sectional and volumetric measures of tumour size

Changes in cross-sectional area are currently used to assess tumour response to treatment. The aims of this study were to validate a helical CT technique for volume determination using a series of phantoms and to compare tumour responses indicated by one-, two- and three-dimensional measures of tumour size change in patients treated for germ cell cancer or lymphoma. All studies were performed on an IGE HiSpeed Advantage helical CT scanner with an Advantage Windows workstation. Phantom volumes were calculated using volume reconstruction software and compared with reference volumes determined by water displacement. 20 lymph node masses were studied on serial CT scans in 16 patients treated with chemotherapy for germ cell cancer or lymphoma. For each lesion the maximum diameter, maximum cross-sectional area and volume were determined before and after treatment. Tumour response was assessed using the standard World Health Organisation criteria (i.e. changes in cross-sectional area) and the newly proposed unidimensional response evaluation criteria in solid tumour (RECIST). The CT volume measurement error was 1.0-5.1% for regularly shaped phantoms larger than 35 cm3. In the assessment of treatment response there was 90% agreement between one-dimensional (1D) and two-dimensional (2D) measurements and 100% agreement between 2D and three-dimensional (3D) measurements. CT volume measurements are accurate and reproducible, particularly for larger structures. Assessment of tumour response using 1D, 2D and 3D measures had limited influence on the classification of treatment response. However, the impact of CT assessment of tumour response using 1D, 2D and 3D measurements on clinical decisions and patient outcome remains to be determined.

Increased impact of acute rejection on chronic allograft failure in recent era

BACKGROUND

Acute rejection (AR) remains a major risk factor for the development of chronic renal allograft failure (CAF), which is a major cause of late graft loss. With the introduction of several newer immunosuppressive agents (e.g., mycophenolate mofetil, tacrolimus and neoral) acute rejection rates have been steadily decreasing. However, the incidence of CAF has not decreased as dramatically as the incidence of acute rejection. One possible explanation is that the impact of AR on CAF is changing. The goal of this study was to analyze the relative impact of AR era on the development of CAF.

METHODS

We evaluated 63,045 primary renal transplant recipients reported to the USRDS from 1988 to 1997. CAF was defined as graft loss after 6 months posttransplantation, censored for death, acute rejection, thrombosis, infection, surgical complications, or recurrent disease. A Cox proportional hazard model correcting for 15 possible confounding factors evaluated the relative impact of AR on CAF. The era effect (years 1988-1989, 1990-1991, 1992-1993, 1994-1995 and 1996-1997) was evaluated by an era versus AR interaction term.

RESULTS

An AR episode within the first 6 months after transplantation was the most important risk factor for subsequent CAF (RR=2.4, CI 2.3-2.5). Compared with the reference group (1988-89 with no rejection), having an AR episode in 1988-89, 1990-1991, 1992-1993, 1994-1995, and 1996-1997, conferred a 1.67, 2.35, 3.4, 4.98 and 5.2-fold relative risk for the subsequent development of CAF (P<0.001).

CONCLUSIONS

Independently of known confounding variables, the impact of AR on CAF has significantly increased from 1988 to 1997. This effect may in part explain the relative lack of improvements in long term renal allograft survival, despite a decline in AR rates.

Radiologic spectrum of craniocervical distraction injuries

Injuries to the atlanto-occipital region, which range from complete atlanto-occipital or atlantoaxial dislocation to nondisplaced occipital condyle avulsion fractures, are usually of critical clinical importance. At initial cross-table lateral radiography, measurement of the basion-dens and basion-posterior axial line intervals and comparison with normal measurements may help detect injury. Computed tomography (CT) with sagittal and coronal reformatted images permits optimal detection and evaluation of fracture and luxation. CT findings that may suggest atlanto-occipital injury include joint incongruity, focal hematomas, vertebral artery injury, capsular swelling, and, rarely, fractures through cranial nerve canals. Magnetic resonance (MR) imaging of the cervical spine with fat-suppressed gradient-echo T2-weighted or short-inversion-time inversion recovery sequences can demonstrate increased signal intensity in the atlantoaxial and atlanto-occipital joints, craniocervical ligaments, prevertebral soft tissues, and spinal cord. Axial gradient-echo MR images may be particularly useful in assessing the integrity of the transverse atlantal ligament. All imaging studies should be conducted with special attention to bone integrity and the possibility of soft-tissue injury. Atlanto-occipital injuries are now recognized as potentially survivable, although commonly with substantial morbidity. Swift diagnosis by the trauma radiologist is crucial for ensuring prompt, effective treatment and preventing delayed neurologic deficits in patients who survive such injuries.

Racial disparities in access to simultaneous pancreas-kidney transplantation in the United States

The purpose of our study is to assess the extent of racial differences in the access to simultaneous pancreas-kidney (SPK) transplantation and evaluate the potential influence of socioeconomic factors on access to transplantation. We performed a retrospective analysis of the US Renal Data System and United Network for Organ Sharing data on all patients with end-stage renal disease (ESRD) due to diabetes mellitus from 1988 to 1996 (n = 562, 814), including all dialysis, wait list, and transplant patients. Racial differences in incidence, prevalence, insurance coverage, employment status, and transplantation rates were calculated. Caucasians had the highest prevalence of ESRD caused by type 1 diabetes (73%), followed by blacks (22%), Hispanics (3%), Native Americans (2%), and others (<1%). Both blacks and Native Americans increased their annual incidence of ESRD caused by insulin-dependent diabetes mellitus by 10% compared with only a 3.5% increase in Caucasians, whereas incidence rates increased annually by almost 8% for both blacks and Native Americans compared with a 3% increase for Caucasians. However, Caucasians received 92% of all SPK transplants, whereas all other racial groups combined received a disproportionate minority of the remaining transplants. Lack of private insurance and unemployment status were associated with annual changes in both incidence of ESRD caused by type 1 diabetes and SPK transplant rates. In conclusion, we observed striking racial disparities for access to SPK transplantation in the United States today, which may be related to employment status, access to private insurance, and subsequent health care. Our preliminary data support current efforts to encourage Medicare and Medicaid coverage for all patients requiring SPK transplantation regardless of racial or financial status.

Effect of waiting time on renal transplant outcome

BACKGROUND

Numerous factors are known to impact on patient survival after renal transplantation. Recent studies have confirmed a survival advantage for renal transplant patients over those waiting on dialysis. We aimed to investigate the hypothesis that longer waiting times are more deleterious than shorter waiting times, that is, to detect a "dose effect" for waiting time.

METHODS

We analyzed 73,103 primary adult renal transplants registered at the United States Renal Data System Registry from 1988 to 1997 for the primary endpoints of death with functioning graft and death-censored graft failure by Cox proportional hazard models. All models were corrected for donor and recipient demographics and other factors known to affect outcome after kidney transplantation.

RESULTS

A longer waiting time on dialysis is a significant risk factor for death-censored graft survival and patient death with functioning graft after renal transplantation (P < 0.001 each). Relative to preemptive transplants, waiting times of 6 to 12 months, 12 to 24 months, 24 to 36, 36 to 48, and over 48 months confer a 21, 28, 41, 53, and 72% increase in mortality risk after transplantation, respectively. Relative to preemptive transplants, waiting times of 0 to 6 months, 6 to 12 months, 12 to 24 months, and over 24 months confer a 17, 37, 55, and 68% increase in risk for death-censored graft loss after transplantation, respectively.

CONCLUSIONS

Longer waiting times on dialysis negatively impact on post-transplant graft and patient survival. These data strongly support the hypothesis that patients who reach end-stage renal disease should receive a renal transplant as early as possible in order to enhance their chances of long-term survival.

Induction of proinflammatory cytokines from human respiratory epithelial cells after stimulation by nontypeable Haemophilus influenzae

Nontypeable Haemophilus influenzae (NTHi) causes repeated respiratory infections in patients with chronic lung diseases. These infections are characterized by a brisk inflammatory response which results in the accumulation of polymorphonucleated cells in the lungs and is dependent on the expression and secretion of proinflammatory cytokines. We hypothesize that multiple NTHi molecules, including lipooligosaccharide (LOS), mediate cellular interactions with respiratory epithelial cells, leading to the production of proinflammatory cytokines. To address this hypothesis, we exposed 9HTEo- human tracheal epithelial cells to NTHi and compared the resulting profiles of cytokine gene expression and secretion using multiprobe RNase protection assays and enzyme-linked immunosorbent assays (ELISA), respectively. Dose-response experiments demonstrated a maximum stimulation of most cytokines tested, using a ratio of 100 NTHi bacterial cells to 1 9HTEo- tracheal epithelial cell. Compared with purified LOS, NTHi bacterial cells stimulated 3.6- and 4.5-fold increases in epithelial cell expression of interleukin-8 (IL-8) and IL-6 genes, respectively. Similar results were seen with epithelial cell macrophage chemotactic protein 1, IL-1alpha, IL-1beta, and tumor necrosis factor alpha expression. Polymyxin B completely inhibited LOS stimulation but only partially reduced NTHi whole cell stimulation. Taken together, these results suggest that multiple bacterial molecules including LOS contribute to the NTHi stimulation of respiratory epithelial cell cytokine production. Moreover, no correlation was seen between NTHi adherence to epithelial cells mediated by hemagglutinating pili, Hia, HMW1, HMW2, and Hap and epithelial cytokine secretion. These data suggest that bacterial molecules beyond previously described NTHi cell surface adhesins and LOS play a role in the induction of proinflammatory cytokines from respiratory epithelial cells.

African-American renal transplant recipients experience decreased risk of death due to infection: possible implications for immunosuppressive strategies

INTRODUCTION

African-American renal transplant recipients tend to experience more acute rejection episodes and have shorter graft survival than Caucasian renal transplant recipients. Various factors have been posited to be responsible for this difference, including relative under immunosuppression. We reasoned that by looking at the balance of acute rejections versus death due to infection, we could ascertain whether African-American renal recipients might have more reserve to tolerate an increase in pharmacological immunosuppression.

METHODS

We analyzed the United States Renal Data System (USRDS) data from 1987 to 1997 regarding acute rejection episodes and infectious deaths. All other pertinent factors were gathered for a multivariate analysis. A total number of 68,885 adult renal transplant recipients were analyzed.

RESULTS

When corrected for all covariates, the relative risk for acute rejection (1.3) was higher although the relative risk for infectious death was lower (0.7) in African-Americans as compared with Caucasians (P<0.01).

CONCLUSION

Our study would indicate that relative to Caucasians, African-American renal transplant recipients are at decreased risk for infectious death and therefore may tolerate the more intensive immunosuppression that may be necessary to narrow the gap in acute rejection rates between African-Americans and Caucasian renal transplant recipients.

Relationship of recipient age and development of chronic allograft failure

BACKGROUND

The elderly are the fastest growing segment of the end stage renal disease (ERSD) population. Older renal transplant recipients experience fewer acute rejection episodes than do younger patients. Despite this, death censored graft survival is no better in these older transplant recipients than in younger recipients. We examined the United States Renal Data System (USRDS) database to determine whether recipient age itself has an independent effect on the development of chronic allograft failure (CAF).

METHODS

We analyzed 59,509 patients from the files of the USRDS. To determine whether age was an independent risk factor for CAF, the population was analyzed separately for Caucasians, African-Americans, and other ethnic groups. All renal transplant recipients from 1988 to 1997 were examined. Both univariate and multivariate analysis were performed using chronic allograft failure as the outcome of interest.

RESULTS

Actuarial 8-year censored graft survival was significantly decreased in the older age groups 67% for ages 18-49 vs. 61.8% for ages 50-64 vs. 50.7% for ages 65+ (P<0.001). In the multivariate analysis, recipient age was a strong and independent risk factor for the development of chronic allograft failure in Caucasians (RR 1.29 for ages 50-64, RR 1.67 for ages older than 65). These findings were reinforced by an analysis that was restricted to living donor transplants without acute rejection.

CONCLUSION

In Caucasians increased recipient age is an independent risk factor for the development of chronic renal allograft failure.

Impact of pre-existing donor hypertension and diabetes mellitus on cadaveric renal transplant outcomes

Hypertension (HTN) and diabetes mellitus (DM) predispose to systemic atherosclerosis with renal involvement. The prevalence of HTN and DM in cadaveric renal donors (affected donors) and the results of transplantation are unknown. We investigated these issues with national data from the US Renal Data System. A total of 4,035 transplants from affected donors were matched 1:1 with unaffected controls according to donor age and race, recipient race, and year of transplantation. Graft and patient survival were estimated. Among the 25,039 solitary renal transplantations performed between July 1, 1994, and June 30, 1997, cadaveric renal transplants from donors with HTN accounted for 15%, and donors with DM, 2%. Programs with 1-year cadaveric renal graft survival rates greater than 90% had 50% less affected donors compared with programs having 1-year cadaveric renal graft survival rates of 85% or less. Compared with donor-age-matched controls, transplants from affected donors were at minimally increased risk for primary nonfunction, delayed graft function, and acute rejection. Three-year graft survival rates were 71% in affected donor organs and 75% in controls (P = 0.001). Compared with controls, duration of HTN was an independent risk factor for graft survival (3-year graft survival rates, 75% versus 65%; relative risk = 1.36 for HTN >10 years; P < 0.001). A substantial fraction of cadaveric renal donors have preexisting HTN. Programs transplanting fewer affected donor kidneys had better than average results. Because the negative impact of donor HTN and DM on transplant outcome was of moderate degree except when the duration of donor HTN was greater than 10 years, use of affected donors should not be discouraged, but graft and patient survival analyses should account for their presence.

Mycophenolate mofetil reduces late renal allograft loss independent of acute rejection

BACKGROUND

Mycophenolate Mofetil (MMF) has been shown to significantly decrease the number of acute rejection episodes in renal transplant recipients during the 1st year. A beneficial effect of MMF on long-term graft survival has been more difficult to demonstrate. This beneficial effect has not been detected, despite the impact of acute rejection on the development of chronic allograft nephropathy and experimental evidence that MMF may have a salutary effect on chronic allograft nephropathy independent of that of rejection.

METHODS

Data on 66,774 renal transplant recipients from the U.S. renal transplant scientific registry were analyzed. Patients who received a solitary renal transplant between October 1, 1988 and June 30, 1997 were studied. The Cox proportional hazard regression was used to estimate relevant risk factors. Kaplan-Meier analysis was performed for censored graft survival.

RESULTS

MMF decreased the relative risk for development of chronic allograft failure (CAF) by 27% (risk ratio [RR] 0.73, P<0.001). This effect was independent of its outcome on acute rejection. Censored graft survival using MMF versus azathioprine was significantly improved by Kaplan-Meier analysis at 4 years (85.61% v. 81.9%). The effect of an acute rejection episode on the risk of developing CAF seems to be increasing over time (RR=1.9, 1988-91; RR=2.9, 1992-94; RR=3.7, 1995-97).

CONCLUSION

MMF therapy decreases the risk of developing CAF. This improvement is only partly caused by the decrease in the incidence of acute rejection observed with MMF; but, is also caused by an effect independent of acute rejection.

Long-term survival in renal transplant recipients with graft function

Long-term survival in renal transplant recipients with graft function.

BACKGROUND

Death with graft function (DWGF) is a common cause of graft loss. The risks and determinants of DWGF have not been studied in a recent cohort of renal transplant recipients. We performed a population-based survival analysis of U.S. patients with end-stage renal disease (ESRD) transplanted between 1988 and 1997.

METHODS

Registry data were used to evaluate long-term patient survival and cause-specific risks of DWGF in 86,502 adult (>/=18 years) renal transplant recipients.

RESULTS

Out of 18,482 deaths, 38% (N = 7040) were deaths with graft function. This accounts for 42. 5% of all graft loss. Patient survival with graft function was 97, 91, and 86% at 1, 5, and 10 years, respectively. The risk of DWGF decreased by 67% (RR = 0.33, P < 0.001) between 1988 and 1997. The adjusted rate of DWGF was 4.6, 0.8, 2.2, and 1.4 deaths per 1000 person-years for cardiovascular disease, stroke, infections, and malignancy, respectively. The suicide rate was 15.7 versus 9.0 deaths per 100,000 person-years in the general population (P < 0. 001). In multivariate analysis, the following factors were independently and significantly predictive of DWGF: white recipient, age at transplantation, ESRD caused by hypertension or diabetes mellitus, length of pretransplant dialysis, delayed graft function, acute rejection, panel reactive antibody> 30%, African American donor race, age> 45 years, and donor death caused by cerebrovascular disease.

CONCLUSIONS

Patients with graft function have a high long-term survival. Although DWGF is a major cause of graft loss, the risk has declined substantially since 1990. Cardiovascular disease was the predominant reported cause of DWGF. Other causes vary by post-transplant time period. Attention to atherosclerotic risk factors may be the most important challenge to further improve the longevity of patients with successful renal transplants.

Cervical spine injury: a clinical decision rule to identify high-risk patients for helical CT screening

OBJECTIVE

We aimed to validate the routine use of a clinical decision rule to direct diagnostic imaging of adult blunt trauma patients at high risk for cervical spine injury.

MATERIALS AND METHODS

We previously developed and have since routinely used a prediction rule based on six clinical parameters to identify patients at greater than 5% risk of cervical spine injury to undergo screening helical CT of the cervical spine. During a 6-month period, 4285 screening imaging studies of the cervical spine were performed in adult blunt trauma patients. Six hundred one patients (398 males, 203 females; age range, 16-100 years; median age, 38 years) underwent helical CT, and the remainder underwent 3684 conventional radiographic examinations. Clinical and report data were extracted from the radiology department database, medical records, and the hospital trauma registry. Abnormal findings were independently confirmed by additional imaging studies, autopsy results, or clinical outcome.

RESULTS

The true-positive cervical spine injury rates in helical CT- and conventional radiography-screened patients who presented directly to our trauma center were 40 (8.7%) of 462 and seven (0.2%) of 3684, respectively. The cervical spine injury rate in patients who were transferred from outside institutions to our trauma center and who underwent helical CT was 37 (26.6%) of 139. This figure included 20 patients already known to have cervical spine fracture.

CONCLUSION

The clinical decision rule can distinguish patients at high and low risk of cervical spine injury, thus supporting its validity.

Growth, carcass characteristics, and incidence of ascites in broilers exposed to environmental fluctuations and oiled litter

The effects of diurnal temperature fluctuations and removal of respirable dust, by application of canola oil to straw litter, on growth, carcass traits, and the degree of ascites was evaluated with 1,200 male broilers studied in two replicated 6-wk trials. Each trial used four pens of 150 birds. The temperature treatment consisted of a fluctuation of 3 C in temperature above the required temperature during the day (0600 to 1800 h) and 3 C below the required temperature at night (1800 to 0600 h) for a 6 C change in daily temperature. The control temperature was constant. All pens had the same mean daily temperature. In each trial, one control temperature pen and one fluctuation temperature pen received bi-weekly applications of canola oil to the litter (1.1 L/m2 of oil over 6 wk). At 6 wk of age, 30 birds from each pen were killed for determination of breast muscle, fatpad, and heart weights. All birds were scored for lesions of ascites at time of processing. A score of 0 or 1 represented slight pericardial effusion, slight pulmonary congestion, and edema. A score of 4 represented birds with marked accumulation of ascitic fluid in one or more ceolomic cavities (other than the pericardium) and advanced liver lesions. A cross-sectional image of each 4-mm heart slice (cross-section of the ventricles) was digitally recorded, and with image analysis we determined the right ventricular area (RVA), left ventricular area (LVA), and total heart area (HA). The final BW of the broilers were significantly different, the oiled-litter treatment (2,249 g) had lower weight gain compared with the nonoiled litter treatment (2,293 g). There were no differences in fatpad weight, shank length, lung weight, and percentage breast muscle between the main treatments. The Pectoralis minor and Pectoralis major weight were significantly heavier in the temperature fluctuation treatment than in the control temperature treatment by 3.0 and 12.0 g, respectively. The birds subjected to the control temperature treatment had a lower RVW than the birds subjected to the fluctuating temperature treatment. Temperature fluctuations also resulted in a 1.4% increase in the incidence of mortality. Temperature fluctuations negatively impact broiler growth due to heat loss when litter oiling was excessive.

Long-term survival in renal transplant recipients with graft function

Long-term survival in renal transplant recipients with graft function.

BACKGROUND

Death with graft function (DWGF) is a common cause of graft loss. The risks and determinants of DWGF have not been studied in a recent cohort of renal transplant recipients. We performed a population-based survival analysis of U.S. patients with end-stage renal disease (ESRD) transplanted between 1988 and 1997.

METHODS

Registry data were used to evaluate long-term patient survival and cause-specific risks of DWGF in 86,502 adult (>/=18 years) renal transplant recipients.

RESULTS

Out of 18,482 deaths, 38% (N = 7040) were deaths with graft function. This accounts for 42. 5% of all graft loss. Patient survival with graft function was 97, 91, and 86% at 1, 5, and 10 years, respectively. The risk of DWGF decreased by 67% (RR = 0.33, P < 0.001) between 1988 and 1997. The adjusted rate of DWGF was 4.6, 0.8, 2.2, and 1.4 deaths per 1000 person-years for cardiovascular disease, stroke, infections, and malignancy, respectively. The suicide rate was 15.7 versus 9.0 deaths per 100,000 person-years in the general population (P < 0. 001). In multivariate analysis, the following factors were independently and significantly predictive of DWGF: white recipient, age at transplantation, ESRD caused by hypertension or diabetes mellitus, length of pretransplant dialysis, delayed graft function, acute rejection, panel reactive antibody> 30%, African American donor race, age> 45 years, and donor death caused by cerebrovascular disease.

CONCLUSIONS

Patients with graft function have a high long-term survival. Although DWGF is a major cause of graft loss, the risk has declined substantially since 1990. Cardiovascular disease was the predominant reported cause of DWGF. Other causes vary by post-transplant time period. Attention to atherosclerotic risk factors may be the most important challenge to further improve the longevity of patients with successful renal transplants.