Utility of KI-67 as a prognostic biomarker in pulmonary neuroendocrine neoplasms: a systematic review and meta-analysis.

OBJECTIVES: Ki-67, a marker of cellular proliferation, is associated with prognosis across a wide range of tumours, including gastroenteropancreatic neuroendocrine neoplasms (NENs), lymphoma, urothelial tumours and breast carcinomas. Its omission from the classification system of pulmonary NENs is controversial. This systematic review sought to assess whether Ki-67 is a prognostic biomarker in lung NENs and, if feasible, proceed to a meta-analysis. RESEARCH DESIGN AND METHODS: Medline (Ovid), Embase, Scopus and the Cochrane library were searched for studies published prior to 28 February 2019 and investigating the role of Ki-67 in lung NENs. Eligible studies were those that included more than 20 patients and provided details of survival outcomes, namely, HRs with CIs according to Ki-67 percentage. Studies not available as a full text or without an English manuscript were excluded. This study was prospectively registered with PROSPERO. RESULTS: Of 11 814 records identified, seven studies met the inclusion criteria. These retrospective studies provided data for 1268 patients (693 TC, 281 AC, 94 large cell neuroendocrine carcinomas and 190 small cell lung carcinomas) and a meta-analysis was carried out to estimate a pooled effect. Random effects analyses demonstrated an association between a high Ki-67 index and poorer overall survival (HR of 2.02, 95% CI 1.16 to 3.52) and recurrence-free survival (HR 1.42; 95% CI 1.01 to 2.00). CONCLUSION: This meta-analysis provides evidence that high Ki-67 labelling indices are associated with poor clinical outcomes for patients diagnosed with pulmonary NENs. This study is subject to inherent limitations, but it does provide valuable insights regarding the use of the biomarker Ki-67, in a rare tumour. PROSPERO REGISTRATION NUMBER: CRD42018093389.

Predicting Ventriculoperitoneal Shunt Dependence in High Grade Aneurysmal Subarachnoid Hemorrhage.

INTRODUCTION: Aneurysmal subarachnoid hemorrhage (aSAH) commonly presents with hydrocephalus due to obstruction of cerebrospinal fluid (CSF) passage across the ventricular system in the brain. Placement of an external ventricular device (EVD) and in some cases ventriculoperitoneal shunt (VPS) are often necessary for patients requiring prolonged CSF diversion. The study aimed at evaluating critical factors that play a role in determining the need for extended extraventricular drainage. METHODS: We performed a retrospective observational cohort study of two groups of patients with radiological imaging confirmed high grade aSAH (Hunt & Hess grades 3-5) who required VPS placement, shunt-dependent group, and who did not require long term CSF diversion, non-shunt-dependent group. We collected and analyzed data regarding the daily CSF output for 10 days following EVD placement, daily EVD height, intracranial pressure (ICP) and cerebral perfusion pressure (CPP), indicators of hydrocephalus, and CSF characteristics. RESULTS: The cohort, comprising of 8 patients in the shunt-dependent group and 32 patients in the non-shunt-dependent group, displayed median daily CSF output of 275.1 mL/day and 193.4 mL/day, respectively (P = .0005). ROC curve for CSF drainage for the two groups showed an area under the curve (AUC) of 0.71 with a 95% confidence interval (CI) 0.65 to 0.77. Qualitative analysis of CSF characteristics revealed that the shunt-dependent group had more proteinaceous, darker red color, and greater proportion of red blood cells (RBCs) although not statistically significant. CONCLUSIONS: Determinants of prolonged CSF drainage requirements in patients with high grade aSAH are not fully elucidated to this date and there is no standardized protocol for CSF diversion. Our study revealed potential markers that can be used in the assessment for the need for long term CSF diversion. Our limited sample size necessitates further research to establish clear correlations and cutoffs of these parameters in predicting long term CSF diversion requirements.

Analysis of Immune Landscape in Pancreatic and Ileal Neuroendocrine Tumours Demonstrates an Immune Cold Tumour Microenvironment.

INTRODUCTION: Neuroendocrine tumours (NETs) are rare tumours with an increasing incidence. While low- and intermediate-grade pancreatic NET (PanNET) and small intestinal NET (siNET) are slow growing, they have a relatively high rate of metastasizing to the liver, leading to substantially worse outcomes. In many solid tumours, the outcome is determined by the quality of the antitumour immune response. However, the quality and significance of antitumour responses in NETs are incompletely understood. This study provides clinico-pathological analyses of the tumour immune microenvironment in PanNET and siNETs. METHODS: Formalin-fixed paraffin-embedded tissue from consecutive resected PanNETs (61) and siNETs (131) was used to construct tissue microarrays (TMAs); 1-mm cores were taken from the tumour centre, stroma, tumour edge, and adjacent healthy tissue. TMAs were stained with antibodies against CD8, CD4, CD68, FoxP3, CD20, and NCR1. T-cell counts were compared with counts from lung cancers. RESULTS: For PanNET, median counts were CD8+ 35.4 cells/mm2, CD4+ 7.6 cells/mm2, and CD68+ macrophages 117.7 cells/mm2. For siNET, there were CD8+ 39.2 cells/mm2, CD4+ 24.1 cells/mm2, and CD68+ 139.2 cells/mm2. The CD8+ cell density in the tumour and liver metastases were significantly lower than in the adjacent normal tissues, without evidence of a cell-rich area at the tumour edge that might have suggested immune exclusion. T-cell counts in lung cancer were significantly higher than those in PanNET and siNETs: CD8+ 541 cells/mm2 and CD4+ 861 cells/mm2 (p ≤ 0.0001). CONCLUSION: PanNETs and siNETs are immune cold with no evidence of T cell exclusion; the low density of immune infiltrates indicates poor antitumour immune responses.

Optimization of Detergent-Mediated Reconstitution of Influenza A M2 Protein into Proteoliposomes.

We report the optimization of detergent-mediated reconstitution of an integral membrane-bound protein, full-length influenza M2 protein, by direct insertion into detergent-saturated liposomes. Detergent-mediated reconstitution is an important method for preparing proteoliposomes for studying membrane proteins, and must be optimized for each combination of protein and membrane constituents used. The purpose of the reconstitution was to prepare samples for site-directed spin-labeling electron paramagnetic resonance (SDSL-EPR) studies. Our goals in optimizing the protocol were to minimize the amount of detergent used, reduce overall proteoliposome preparation time, and confirm the removal of all detergent. The liposomes were comprised of (1-palmitoyl-2-oleyl-sn-glycero-phosphocholine (POPC) and 1-palmitoyl-2-oleyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (POPG), and the detergent octylglucoside (OG) was used for reconstitution. Rigorous physical characterization was applied to optimize each step of the reconstitution process. We used dynamic light scattering (DLS) to determine the amount of OG needed to saturate the preformed liposomes. During detergent removal by absorption with Bio-Beads, we quantified the detergent concentration by means of a colorimetric assay, thereby determining the number of Bio-Bead additions needed to remove all detergent from the final proteoliposomes. We found that the overnight Bio-Bead incubation used in previously published protocols can be omitted, reducing the time needed for reconstitution. We also monitored the size distribution of the proteoliposomes with DLS, confirming that the size distribution remains essentially constant throughout the reconstitution process.

C-terminal juxtamembrane region of full-length M2 protein forms a membrane surface associated amphipathic helix.

The influenza A M2 protein is a 97-residue integral membrane protein involved in viral budding and proton conductance. Although crystal and NMR structures exist of truncated constructs of the protein, there is disagreement between models and only limited structural data are available for the full-length protein. Here, the structure of the C-terminal juxtamembrane region (sites 50-60) is investigated in the full-length M2 protein using site-directed spin-labeling electron paramagnetic resonance (EPR) spectroscopy in lipid bilayers. Sites 50-60 were chosen for study because this region has been shown to be critical to the role the M2 protein plays in viral budding. Continuous wave EPR spectra and power saturation data in the presence of paramagnetic membrane soluble oxygen are consistent with a membrane surface associated amphipathic helix. Comparison between data from the C-terminal juxtamembrane region in full-length M2 protein with data from a truncated M2 construct demonstrates that the line shapes and oxygen accessibilities are remarkably similar between the full-length and truncated form of the protein.

A pathologist's survey on the reporting of sessile serrated adenomas/polyps.

AIM: The purpose of this survey was to ascertain reporting habits of pathologists towards sessile serrated adenomas/polyps (SSA/P). METHODS: A questionnaire designed to highlight diagnostic criteria, approach and clinical implications of SSA/P was circulated electronically to 45 pathologists in the UK and North America. RESULTS: Forty-three of 45 pathologists agreed to participate. The vast majority (88%) had a special interest in gastrointestinal (GI) pathology, had great exposure to GI polyps in general with 40% diagnosing SSA/P at least once a week if not more, abnormal architecture was thought by all participants to be histologically diagnostic, and 11% would make the diagnosis if a single diagnostic histological feature was present in one crypt only, while a further 19% would diagnose SSA/P in one crypt if more than one diagnostic feature was present. The vast majority agreed that deeper sections were useful and 88% did not feel proliferation markers were useful. More than one-third did not know whether, or did not feel that, their clinicians were aware of the implications of SSA/P. CONCLUSIONS: 98% of pathologists surveyed are aware that SSA/P is a precursor lesion to colorectal cancer, the majority agree on diagnostic criteria, and a significant number feel that there needs to be greater communication and awareness among pathologists and gastroenterologists about SSA/P.

Accuracy of visual assessments of proliferation indices in gastroenteropancreatic neuroendocrine tumours.

AIMS: To compare the accuracy of eyeball estimates of the Ki-67 proliferation index (PI) with formal counting of 2000 cells as recommend by the Royal College of Pathologists. METHODS: Sections from gastroenteropancreatic neuroendocrine tumours were immunostained for Ki-67. PI was calculated using three methods: (1) a manual tally count of 2000 cells from the area of highest nuclear labelling using a microscope eyepiece graticule; (2) eyeball estimates made by four pathologists within the same area of highest nuclear labelling; and (3) image analysis of microscope photographs taken from this area using the ImageJ 'cell counter' tool. ImageJ analysis was considered the gold standard for comparison. RESULTS: Levels of agreement between methods were evaluated using Bland-Altman plots. Agreement between the manual tally and ImageJ assessments was very high at low PIs. Agreement between eyeball assessments and ImageJ analysis varied between pathologists. Where data for low PIs alone were analysed, there was a moderate level of agreement between pathologists' estimates and the gold standard, but when all data were included, agreement was poor. CONCLUSIONS: Manual tally counts of 2000 cells exhibited similar levels of accuracy to the gold standard, especially at low PIs. Eyeball estimates were significantly less accurate than the gold standard. This suggests that tumour grades may be misclassified by eyeballing and that formal tally counting of positive cells produces more reliable results. Further studies are needed to identify accurate clinically appropriate ways of calculating.

Concurrent visualization in a production supercomputing environment.

We describe a concurrent visualization pipeline designed for operation in a production supercomputing environment. The facility was initially developed on the NASA Ames "Columbia" supercomputer for a massively parallel forecast model (GEOS4). During the 2005 Atlantic hurricane season, GEOS4 was run 4 times a day under tight time constraints so that its output could be included in an ensemble prediction that was made available to forecasters at the National Hurricane Center. Given this time-critical context, we designed a configurable concurrent pipeline to visualize multiple global fields without significantly affecting the runtime model performance or reliability. We use MPEG compression of the accruing images to facilitate live low-bandwidth distribution of multiple visualization streams to remote sites. We also describe the use of our concurrent visualization framework with a global ocean circulation model, which provides a 864-fold increase in the temporal resolution of practically achievable animations. In both the atmospheric and oceanic circulation models, the application scientists gained new insights into their model dynamics, due to the high temporal resolution animations attainable.

Lower gastrointestinal bleeding--management.

Although acute LGIB is only about one fifth as common and is usually less hemodynamically significant than upper gastrointestinal bleeding, it presents numerous unique clinical challenges. The best diagnostic approach for patients with active bleeding is unknown, but urgent prepared colonoscopy is safe and likely to be beneficial (Fig. 3, Table 2). In patients who have aggressive bleeding or recurrent bleeding, it is critical for the practitioner to judge when angiography and surgery are necessary.

Urgent colonoscopy for evaluation and management of acute lower gastrointestinal hemorrhage: a randomized controlled trial.

OBJECTIVES: We hypothesized that early intervention in patients with lower gastrointestinal bleeding (LGIB) would improve outcomes and therefore conducted a prospective randomized study comparing urgent colonoscopy to standard care. METHODS: Consecutive patients presenting with LGIB without upper or anorectal bleeding sources were randomized to urgent purge preparation followed immediately by colonoscopy or a standard care algorithm based on angiographic intervention and expectant colonoscopy. RESULTS: A total of 50 patients were randomized to each group. A definite source of bleeding was found more often in urgent colonoscopy patients (diverticula, 13; angioectasia, 4; colitis, 4) than in the standard care group (diverticula, 8; colitis, 3) (the odds ratio for the difference among the groups was 2.6; 95% CI 1.1-6.2). In the urgent colonoscopy group, 17 patients received endoscopic therapy; in the standard care group, 10 patients had angiographic hemostasis. There was no difference in outcomes among the two groups-including: mortality 2%versus 4%, hospital stay 5.8 versus 6.6 days, ICU stay 1.8 versus 2.4 days, transfusion requirements 4.2 versus 5 units, early rebleeding 22%versus 30%, surgery 14%versus 12%, or late rebleeding 16%versus 14% (mean follow-up of 62 and 58 months). CONCLUSION: Although urgent colonoscopy identified a definite source of LGIB more often than a standard care algorithm based on angiography and expectant colonoscopy, the approaches are not significantly different with regard to important outcomes. Thus, decisions concerning care for patients with acute LGIB should be based on individual experience and local expertise.

The perception of cancer risk in patients with prevalent Barrett's esophagus enrolled in an endoscopic surveillance program.

BACKGROUND & AIMS: Patients with Barrett's esophagus (BE) have a risk of esophageal adenocarcinoma of approximately 0.5% per year. Patients may have difficulty understanding this risk. This study assessed the perceived risk of cancer in patients with BE, and correlated their risk estimates with their health care use behaviors. METHODS: We performed a survey of patients with BE participating in an endoscopic surveillance program at 2 sites: a university teaching hospital and a Veterans' Administration hospital. A questionnaire also elicited their demographics as well as their sources of health information. Health care behaviors, including physician visits and endoscopic surveillance behaviors, were assessed. Patients were classified as either overestimators or nonoverestimators of risk. Characteristics of overestimators, as well as health care use patterns, were assessed. RESULTS: One hundred eighteen patients met entry criteria, and 92 (78%) completed all the questionnaires. Sixty-eight percent of patients overestimated their 1-year risk of cancer, with a mean estimated 1-year cancer risk being 13.6%. The lifetime risk also was overestimated by 38% of patients. Patients who overestimated risk were more likely to be Veterans' Administration medical center patients, have more symptomatic reflux, and were more likely to use the Internet to get health care information. There was no significant difference in physician visits between overestimators and nonestimators (1.2 visits per year vs 1.0, P = .20), nor in endoscopy use (5.7 endoscopies per 5-year period vs 5.0, P = .42). CONCLUSIONS: The majority of patients with prevalent BE participating in an endoscopic surveillance program overestimated their chances of developing adenocarcinoma of the esophagus. Efforts to improve education of such patients with BE are warranted.

Ischemic colitis: a clinical review.

Ischemic colitis is the most common form of intestinal ischemia. It manifests as a spectrum of injury from transient self-limited ischemia involving the mucosa and submucosa to acute fulminant ischemia with transmural infarction that may progress to necrosis and death. Although there are a variety of causes, the most common mechanism is an acute, self-limited compromise in intestinal blood flow. Patients typically have mild abdominal pain and tenderness over the involved segment of bowel. There is usually passage of blood mixed with stool, but hemodynamically significant bleeding is unusual. Although computed tomography may have suggestive findings, colonoscopy is the procedure of choice for diagnosis. Supportive care with intravenous fluids, optimization of hemodynamic status, avoidance of vasoconstrictive drugs, bowel rest, and empiric antibiotics will produce clinical improvement within 1 to 2 days in most patients. Twenty percent of patients will have development of peritonitis or may deteriorate despite conservative management and will require surgery.

Most GERD symptoms are not due to acid reflux in patients with very low 24-hour acid contact times.

Ambulatory esophageal 24-hr pH monitoring is used to diagnose GERD by determining the total acid contact time and/or symptom index (SI). The aim of this study was to compare the relationship between total acid contact times and SI in two groups: patients with very low vs. very high total acid contact times. We reviewed 973 consecutive 24-hr pH studies and compared patients with the lowest and highest 5% of total acid contact times. The low reflux group was significantly younger (median 50 vs. 54 years) and more predominantly female (78 vs. 47%) than the high reflux group. Median total acid contact time was 0.6 and 26.4% in the low and high reflux groups, respectively. The median SI was significantly lower in the low vs. high reflux groups for all symptoms (heartburn, 0 vs. 100%; regurgitation, 20 vs. 100%; cough, 0 vs. 55%; chest pain, 0 vs. 75%; nausea, 0 vs. 100%; and total SI, 12 vs. 86%). In patients with very low total acid contact times, only 12% of symptoms (typical or atypical) are associated with acid reflux, compared to 86% in patients with very high acid contact times. Younger females are overrepresented in the very low reflux, low SI group.

Massive gastrointestinal hemorrhage due to rupture of a donor pancreatic artery pseudoaneurysm in a pancreas transplant patient.

Enteric drainage of secretions by anastomosing the donor duodenum to the recipient's small bowel has become common in pancreatic transplantation. While it eliminates many problems, endoscopic access to the transplanted duodenum and pancreas is made difficult. After a pancreas kidney transplant, the patient presented with massive hematochezia. Upper and lower endoscopy revealed large amounts of red blood in the colon but no specific bleeding site. Mesenteric angiography was normal but pelvic angiography showed rapid extravasation of contrast from a pseudoaneurysm of the pancreatic transplant artery. This was successfully embolized with coils. To the best of our knowledge, this is the first case of massive gastrointestinal hemorrhage because of rupture of a pseudoaneurysm of the donor pancreatic artery in a pancreas transplant patient. We report this case and review our institution's experience with all forms of gastrointestinal bleeding in pancreas transplant patients.

Gastrointestinal endoscopic evaluation of premenopausal women with iron deficiency anemia.

GOALS: To evaluate whether the gastrointestinal tract could be a source of chronic blood loss in premenopausal women with iron deficiency anemia. BACKGROUND: While premenopausal women with iron deficiency anemia are typically managed with simple iron replacement, the standard of care for postmenopausal women and men is to exclude a gastrointestinal source of bleeding. STUDY: We identified 111 premenopausal women who underwent endoscopy for the sole indication of iron deficiency anemia. RESULTS: The mean age was 42.5 years. Lesions potentially causative of iron deficiency anemia were detected in 22 patients (20%). Upper gastrointestinal lesions were present in 14 patients (13%) and included only erosive lesions. Lower gastrointestinal lesions were detected in 8 patients (7.2%) and included colon cancer (2.7%), inflammatory bowel disease (3.6%), and a colonic ulcer >1 cm (0.9%). Patients with upper gastrointestinal lesions were more likely to use aspirin or nonsteroidal antiinflammatory drugs (11/14, 79%) than patients with no lesions (26/89, 23%; P = 0.043). Occult blood was more common in patients with lower gastrointestinal lesions 8/8 (100%) and patients with upper gastrointestinal lesions (9/14, 64%) than in patients without lesions (28/89, 31%; P = 0.037 and 0.039). Gastrointestinal symptoms were significantly more common in patients with gastrointestinal lesions than in patients without lesions. CONCLUSIONS: A gastrointestinal source of chronic blood loss was identified in a substantial proportion of premenopausal women with iron deficiency anemia. Patients with gastrointestinal symptoms, fecal occult blood, and/or weight loss should undergo endoscopy.