Marek's disease virus US3 protein kinase phosphorylates chicken HDAC 1 and 2 and regulates viral replication and pathogenesis.

Marek's disease virus (MDV) is a potent oncogenic alphaherpesvirus that elicits a rapid onset of malignant T-cell lymphomas in chickens. Three MDV types, including GaHV-2 (MDV-1), GaHV-3 (MDV-2) and MeHV-1 (HVT), have been identified and all encode a US3 protein kinase. MDV-1 US3 is important for efficient virus growth in vitro. To study the role of US3 in MDV replication and pathogenicity, we generated an MDV-1 US3-null virus and chimeric viruses by replacing MDV-1 US3 with MDV-2 or HVT US3. Using MD as a natural virus-host model, we showed that both MDV-2 and HVT US3 partially rescued the growth deficiency of MDV-1 US3-null virus. In addition, deletion of MDV-1 US3 attenuated the virus resulting in higher survival rate and lower MDV specific tumor incidence, which could be partially compensated by MDV-2 and HVT US3. We also identified chicken histone deacetylase 1 (chHDAC1) as a common US3 substrate for all three MDV types while only US3 of MDV-1 and MDV-2 phosphorylate chHDAC2. We further determined that US3 of MDV-1 and HVT phosphorylate chHDAC1 at serine 406 (S406), while MDV-2 US3 phosphorylates S406, S410, and S415. In addition, MDV-1 US3 phosphorylates chHDAC2 at S407, while MDV-2 US3 targets S407 and S411. Furthermore, biochemical studies show that MDV US3 mediated phosphorylation of chHDAC1 and 2 affect their stability, transcriptional regulation activity, and interaction network. Using a class I HDAC specific inhibitor, we showed that MDV US3 mediated phosphorylation of chHDAC1 and 2 is involved in regulation of virus replication. Overall, we identified novel substrates for MDV US3 and characterized the role of MDV US3 in MDV pathogenesis.

NCCN Guidelines® Insights: Biliary Tract Cancers, Version 2.2023.

In 2023, the NCCN Guidelines for Hepatobiliary Cancers were divided into 2 separate guidelines: Hepatocellular Carcinoma and Biliary Tract Cancers. The NCCN Guidelines for Biliary Tract Cancers provide recommendations for the evaluation and comprehensive care of patients with gallbladder cancer, intrahepatic cholangiocarcinoma, and extrahepatic cholangiocarcinoma. The multidisciplinary panel of experts meets at least on an annual basis to review requests from internal and external entities as well as to evaluate new data on current and emerging therapies. These Guidelines Insights focus on some of the recent updates to the NCCN Guidelines for Biliary Tract Cancers as well as the newly published section on principles of molecular testing.

Neoadjuvant Chemoradiation Impacts the Prognostic Effect of Surgical Margin Status in Pancreatic Adenocarcinoma.

BACKGROUND: Many studies show significantly improved survival after R0 resection compared with R1 resection in pancreatic adenocarcinoma (PAC); however, the effect of neoadjuvant chemoradiation (NACRT) on this association is unknown. OBJECTIVE: The aim of this study was to evaluate the prognostic significance of positive surgical margins (SMs) after NACRT compared with upfront surgery + adjuvant therapy in PAC. METHODS: All cases of surgically resected PAC at a single institution were reviewed from 1996 to 2014; patients treated with palliative intent, metastatic disease, and biliary/ampullary tumors were excluded. The primary endpoint was overall survival (OS). RESULTS: Overall, 300 patients were included; 134 patients received NACRT with concurrent 5-fluorouracil or gemcitabine followed by surgery, and 166 patients received upfront surgery (+ adjuvant chemotherapy in 72% of patients and RT in 65%); 31% of both groups had a positive SM (+SM). The median OS for patients with a +SM or negative SM (-SM) was 26.6 and 31.6 months, respectively for NACRT, and 12.0 and 24.5 months, respectively, for upfront surgery. OS was significantly improved with -SM compared with +SM in both groups (p = 0.006). When resection yielded +SM, NACRT patients had improved OS compared with upfront surgery patients (p < 0.001). On multivariable analysis, +SM in the upfront surgery group (hazard ratio [HR] 2.94, 95% confidence interval [CI] 2.04-4.24; p < 0.001) and older age (HR 1.01, 95% CI 1.00-1.03, per year; p = 0.007) predicted worse OS. +SM in the NACRT group was not associated with worse OS (HR 1.09, 95% CI 0.72-1.65; p = 0.70). CONCLUSION: Patients with a positive margin after NACRT and surgery had longer survival compared with patients with a positive margin after upfront surgery. NACRT should be strongly considered for patients at high risk of R1 resections.

Total Neoadjuvant Treatment for Pancreatic Ductal Adenocarcinoma Is Associated With Limited Lymph Node Yield but Improved Ratio.

INTRODUCTION: The lymph node yield (LNY) and lymph node ratio (LNR) of nodal metastases following pancreatoduodenectomy (PD) have been reported as prognostic parameters in patients with pancreatic ductal adenocarcinoma (PDAC). However, they have not been compared in the setting of various neoadjuvant therapy modalities. METHODS: A single institutional retrospective study identified 134 patients diagnosed with resectable, BLR- and LA-PDAC who underwent PD at Fox Chase Cancer Center between 2010 and 2019. Patients were categorized based on first-line treatment as follows: surgery first (SF), total neoadjuvant therapy (TNT), and single modality neoadjuvant therapy (SMNT). The histopathological reports of the surgical specimens were examined to obtain LNY and determine the counts of lymph nodes with metastases. Subsequently, LNR was calculated as the number of positive lymph nodes divided by the number of lymph nodes examined. RESULTS: Overall, 49, 38, 27, 12, and 8 patients underwent SF approach, SMNT, incomplete TNT, induction TNT, and consolidation TNT, respectively. There was no difference in R0 resection and vascular resection between the groups (P = 0.096 and 0.794, respectively). The median counts of LNY were 22, 15, 21, 11.5, and 10, respectively (P < 0.001). The average LNR was 0.16, 0.07, 0.03, 0.02, and 0.02, respectively (P < 0.001). There were statistically significant differences in overall survival in the TNT groups (log-rank test P = 0.030). CONCLUSIONS: PDAC patients who undergo the TNT modality exhibit lower LNY and improved LNR compared with the SF approach and SMNT neoadjuvant therapy groups. This is likely explained by the increased treatment response and lymph node obliteration associated with the TNT approach. Our results question the minimal requirement of 11-18 harvested lymph nodes for PD following TNT.

Total neoadjuvant therapy is associated with improved overall survival and pathologic response in pancreatic adenocarcinoma.

BACKGROUND: Few studies have evaluated outcomes of total neoadjuvant therapy (TNT) compared with single modality neoadjuvant therapy (SMNT) or surgery first (SF) for pancreatic ductal adenocarcinoma (PDAC). METHODS: A single-institution retrospective review of PDAC patients who underwent pancreatectomy was conducted (1993-2019). Overall survival (OS) estimates from diagnosis and from surgery were determined using Kaplan-Meier methods; Cox proportional hazards models adjusted for covariates. RESULTS: Surgery was performed upfront (SF) in 168 (46.9%), while 111 (31.0%) had chemotherapy or chemoradiation before resection (SMNT), and 79 (22.1%) underwent TNT (chemotherapy and chemoradiation). Resection margins were more frequently R0 in the TNT group (86.1%) compared with SMNT (64.0%) and SF (72%) (p < 0.001). Complete pathologic response was more common in the TNT group (10.1%) compared with SMNT (3.6%) or SF (0.6%) (p = 0.001), resulting in prolonged survival (median OS = 100.2 months). TNT patients demonstrated longer median OS from surgery (33.6 months) compared with SF (19.1 months) and SMNT (17.4 months) (p = 0.010), which persisted after controlling for covariates. CONCLUSIONS: TNT is associated with more frequent complete pathologic response, a higher rate of margin negative resection, and prolonged OS as compared with SF or SMNT. Additional studies to identify subgroups that derive the greatest benefit are warranted.

The role of Meq-vIL8 in regulating Marek's disease virus pathogenesis.

Marek's disease virus (MDV) is a highly cell-associated oncogenic alphaherpesvirus that causes T cell lymphoma in chickens. MDV-encoded Meq and vIL8 proteins play important roles in transformation and early cytolytic infection, respectively. Previous studies identified a spliced transcript, meq-vIL8, formed by alternative splicing of meq and vIL8 genes in MDV lymphoblastoid tumour cells. To determine the role of Meq-vIL8 in MDV pathogenesis, we generated a recombinant MDV (MDV-meqΔSD) by mutating the splice donor site in the meq gene to abrogate the expression of Meq-vIL8. As expected, our results show that MDV-meqΔSD virus grows similarly to the parental and revertant viruses in cell culture, suggesting that Meq-vIL8 is dispensable for MDV growth in vitro. We further characterized the pathogenic properties of MDV-meqΔSD virus in chickens. Our results show that lack of Meq-vIL8 did not affect virus replication during the early cytolytic phase, as determined by immunohistochemistry analysis and/or viral genome copy number, but significantly enhanced viral DNA load in the late phase of infection in the spleen and brain of infected chickens. In addition, we observed that abrogation of Meq-vIL8 expression reduced the mean death time and increased the prevalence of persistent neurological disease, common features of highly virulent strains of MDV, in inoculated chickens. In conclusion, our study shows that Meq-vIL8 is an important virulence factor of MDV.

Role of Marek's Disease Virus (MDV)-Encoded US3 Serine/Threonine Protein Kinase in Regulating MDV Meq and Cellular CREB Phosphorylation.

Marek's disease (MD) is a neoplastic disease of chickens caused by Marek's disease virus (MDV), a member of the subfamily Alphaherpesvirinae Like other alphaherpesviruses, MDV encodes a serine/threonine protein kinase, US3. The functions of US3 have been extensively studied in other alphaherpesviruses; however, the biological functions of MDV US3 and its substrates have not been studied in detail. In this study, we investigated potential cellular pathways that are regulated by MDV US3 and identified chicken CREB (chCREB) as a substrate of MDV US3. We show that wild-type MDV US3, but not kinase-dead US3 (US3-K220A), increases CREB phosphorylation, leading to recruitment of phospho-CREB (pCREB) to the promoter of the CREB-responsive gene and activation of CREB target gene expression. Using US3 deletion and US3 kinase-dead recombinant MDV, we identified US3-responsive MDV genes during infection and found that the majority of US3-responsive genes were located in the MDV repeat regions. Chromatin immunoprecipitation sequencing (ChIP-seq) studies determined that some US3-regulated genes colocalized with Meq (an MDV-encoded oncoprotein) recruitment sites. Chromatin immunoprecipitation-PCR (ChIP-PCR) further confirmed Meq binding to the ICP4/LAT region, which is also regulated by US3. Furthermore, biochemical studies demonstrated that MDV US3 interacts with Meq in transfected cells and MDV-infected chicken embryonic fibroblasts in a phosphorylation-dependent manner. Finally, in vitro kinase studies revealed that Meq is a US3 substrate. MDV US3 thus acts as an upstream kinase of the CREB signaling pathway to regulate the transcription function of the CREB/Meq heterodimer, which targets cellular and viral gene expression.IMPORTANCE MDV is a potent oncogenic herpesvirus that induces T-cell lymphoma in infected chickens. Marek's disease continues to have a significant economic impact on the poultry industry worldwide. US3 encoded by alphaherpesviruses is a multifunctional kinase involved in the regulation of various cellular pathways. Using an MDV genome quantitative reverse transcriptase PCR (qRT-PCR) array and chromatin immunoprecipitation, we elucidated the role of MDV US3 in viral and cellular gene regulation. Our results provide insights into how viral kinase regulates host cell signaling pathways to activate both viral and host gene expression. This is an important step toward understanding host-pathogen interaction through activation of signaling cascades.

Treatment at an Academic Cancer Center Confers Better Survival by Stage for Signet-Ring Cell and Non-signet-Ring Cell Gastric Cancer.

BACKGROUND: The literature lacks large-scale population studies comparing survival outcomes between signet-ring cell gastric carcinoma (SRGC) and non-SRGC (NSRGC) when treatment is delivered at academic versus community cancer centers. METHODS: The National Cancer Database (NCDB) from 2004 to 2016 was queried to examine the association between treatment facility category and overall survival of patients who underwent gastrectomy for resectable gastric adenocarcinoma (GAC). RESULTS: The study investigated 22,871 patients. Upstaging of resectable GAC to pathologic stage 4 was more evident at community centers (3.5%) than at academic centers (2.8%) for the NSRGC variant (p = 0.211), whereas it was comparable between the two facility categories for the SRGC variant (5.9% vs 6%, respectively). Patients with pathologic stage 1 or 3 NSRGC who underwent gastrectomy at academic programs had better overall survival (OS) (hazard ratio [HR], 0.68; p < 0.0001) than those who underwent gastrectomy at community centers (HR, 0.79; p < 0.0065). Similarly, patients with stage 2 SRGC had better OS when treated at academic versus community centers (HR, 0.54; p = 0.0019). No statistically significant improvement in OS was observed between patients with stage 2 NSRGC (HR, 0.84; p = 0.083) and those with stage 3 SRGC (HR, 0.78; p = 0.054) who were treated at academic centers. No survival benefit was demonstrated for stage 1 SRGC when academic and community centers were compared (p = 0.56). CONCLUSIONS: This is the first study based on a large-scale database in the Western population that addressed the overall survival-by-stage of two distinct GAC histologic variants. Treatment at academic centers was associated with significant improvements in OS.

Enhanced Supernova Axion Emission and Its Implications.

We calculate the axion emission rate from reactions involving thermal pions in matter encountered in supernovae and neutron star mergers, identify unique spectral features, and explore their implications for astrophysics and particle physics. We find that it is about 2-5 times larger than nucleon-nucleon bremsstrahlung, which in past studies was considered to be the dominant process. The axion spectrum is also found be much harder. Together, the larger rates and higher axion energies imply a stronger bound on the mass of the QCD axion and better prospects for direct detection in a large underground neutrino detector from a nearby galactic supernova.

Hepatobiliary Cancers, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.

The NCCN Guidelines for Hepatobiliary Cancers focus on the screening, diagnosis, staging, treatment, and management of hepatocellular carcinoma (HCC), gallbladder cancer, and cancer of the bile ducts (intrahepatic and extrahepatic cholangiocarcinoma). Due to the multiple modalities that can be used to treat the disease and the complications that can arise from comorbid liver dysfunction, a multidisciplinary evaluation is essential for determining an optimal treatment strategy. A multidisciplinary team should include hepatologists, diagnostic radiologists, interventional radiologists, surgeons, medical oncologists, and pathologists with hepatobiliary cancer expertise. In addition to surgery, transplant, and intra-arterial therapies, there have been great advances in the systemic treatment of HCC. Until recently, sorafenib was the only systemic therapy option for patients with advanced HCC. In 2020, the combination of atezolizumab and bevacizumab became the first regimen to show superior survival to sorafenib, gaining it FDA approval as a new frontline standard regimen for unresectable or metastatic HCC. This article discusses the NCCN Guidelines recommendations for HCC.

Partial Gastrectomy is Associated with Improved Overall Survival in Signet-Ring Cell Gastric Cancer.

BACKGROUND: Signet-ring cell gastric cancer (SRGC) is a histological variant of gastric adenocarcinoma (GAC) with a worse prognosis compared to non-signet-ring cell gastric cancer (NSRGC). To our knowledge, the overall survival (OS) among patients with SRGC undergoing total/near-total (TG) versus partial gastrectomy (PG) has never been reported from a large-scale Western database. METHODS: We performed a retrospective analysis of patients with both SRGC and NSRGC using The National Cancer Database. RESULTS: In total, 17,086 patients were included. Patients who underwent TG versus PG were 25.5% (n = 770) versus 74.5% (n = 2246) for SRGC, and 20.9% (n = 2943) versus 79.1% (n = 11,127) for NSRGC, respectively. Patients who had SRGC were more likely to undergo TG (25.5% versus 20.9% P< 0.0001). Patients with distal gastric tumors were less likely to undergo TG (16.5% versus 25.4% P < 0.0001). Patients undergoing PG for the SRGC histological variant had better OS (HR = 0.68, CI=0.61-0.76; P < 0.0001) versus those who underwent TG. Similarly, NSRGC patients undergoing PG also had improved OS, but to a lesser extent (HR = 0.91, CI = 0.85-0.96; P= 0.002). Overall, PG for GAC was associated with improved OS compared to TG, although the OS benefit is more profound in the SRGC histological variant (P < 0.0001). CONCLUSIONS: Our results show that TG is not associated with improved OS in patients who undergo gastrectomy for GAC, even when adjusted for tumor location. The survival differences are more pronounced in the SRGC histology variant. The worst survival is observed in patients with SRGC who undergo TG after adjusting for different covariates.

Clinical and Histological Basis of Adenosquamous Carcinoma of the Pancreas: A 30-year Experience.

BACKGROUND: Adenosquamous carcinoma (ASC) of the pancreas is a rare form of malignancy with a poor prognosis. We herein report our case series with review of the contemporary literature. METHODS: With institutional review board approval, we identified 23 patients with pancreatic ASC. RESULTS: ASC was more common in women (61%), with a median age of 73 y at presentation. The tumor was in the head of the pancreas in 65% of cases. Six cases (26%) had resectable disease, three (13%) were borderline resectable, and eight (34.7%) were locally advanced or metastatic. First-line treatment included pancreatic resection in eight cases (34.8%), concurrent neoadjuvant chemoradiation in three (13%), and neoadjuvant chemotherapy in two (8.7%). Most resected tumors had pathological T3 stage (80%). Pathological nodal disease was demonstrated in 60%, and margins were positive in three cases. Complete pathological response was not observed, although fibrosis presented in only one case (10%). Eventually, twenty patients developed metastatic disease. Overall survival is 11.5 [95% confidence interval 6, 14.5] months. CONCLUSIONS: ASC demonstrates a more aggressive malignant phenotype and carries a worse prognosis. Oncological resection is the mainstay of treatment. Neoadjuvant chemoradiation is an emerging approach in the management of ASC that has been extrapolated from the adenocarcinoma neoadjuvant trials.

A Retrospective, Observational Analysis of Tumor Infiltrating Lymphocytes and Tumor Regression in Melanoma.

BACKGROUND: Tumor infiltrating lymphocytes (TILs) and regression are thought to be distinct markers of the immune response to melanoma. OBJECTIVE: This study sought to analyze the relationship of TIL grade and presence of regression to each other and to other prognostic histopathologic and clinical values in melanoma. MATERIALS AND METHODS: A retrospective analysis was conducted using patients diagnosed with melanoma between 2013 and 2019 whose complete histopathologic reports were available. RESULTS: Regression was seen in 48.9%, 30.1% and 37.9% of patients with brisk, non-brisk, and absent TILs respectively (P=0.019). Melanoma tumors with brisk TILs were found to have a lower Breslow thickness than those with non-brisk or absent (P= 0.001). Tumors with regression were also found to have lower Breslow thickness (P<0.001). Neither TIL grade nor regression were protective of nodal metastasis or associated with improved survival. CONCLUSION: Brisk TILs have a positive association with thinner tumors and the presence of tumor regression relative to non-brisk or absent TILs. This may suggest a more robust immune response in tumors with brisk TILs. Further exploration of the interplay between TIL grade, lymphocyte cell subtype and lymphocyte density may help explain this finding.

Beyond property or beyond Piketty?

Capital and Ideology represents a significant further statement from Thomas Piketty. The arguments made by the "New Piketty" are largely compatible with those of his previous Capital in the Twenty-First Century, but reflect broadening of scope and deepening of causal analysis, most markedly through the adoption of a world historical perspective. The result is a fuller offering for understanding inequality's pattern in the world, why it exists and how we can best respond to it. The book presents a wide range of arguments, which do not on first glance appear unified. This review essay distills these into six propositions, describes and evaluates each in turn, and identifies some threads that link them. In the process, it provides a critical assessment of Capital and Ideology.

Severe Hypocalcemia and Transient Hypoparathyroidism After Hyperthermic Intraperitoneal Chemotherapy.

Dear Editors,Hypocalcemia is not unusual in patients hospitalized for critical illness and has also been described after general surgery in addition to head and neck surgical procedures 1 2 3. Hypocalcemic events commonly occur in the setting of massive blood transfusion, albumin deficiency, vitamin D deficiency, and/or hypomagnesemia. In the absence of these factors, only slight decreases in calcium levels within the normal range have been reported during surgical procedures 1. Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC) causing asymptomatic hypocalcemia has only been reported in two previous studies 4 5. The etiology is unclear. We here report a patient who developed severe symptomatic hypocalcemia likely as a result of a profound inflammatory reaction with transient hypoparathyroidism after HIPEC.

Treatment Patterns and Distance to Treatment Facility for Soft Tissue Sarcoma of the Extremity.

BACKGROUND: The impact that distance traveled to receive treatment has on treatments and outcomes among patients with soft tissue sarcoma (STS) of the extremity has yet to be thoroughly investigated. METHODS: Information on patients treated for STS of the extremity between 2006 and 2015 was obtained from the National Cancer Database. Patients were stratified into two groups based on median distance traveled to receive treatment. Chi-square tests assessed associations between categorical variables and distance to treatment. Kaplan-Meier survival estimates and Cox regression were used to estimate survival. RESULTS: The sample included 21,763 patients. The mean age was 59.3 y, 54.6% were men, and 83.2% were white. The median distance traveled to the treating facility was 15.6 miles. Compared with patients who traveled <15 miles, those who traveled ≥15 miles were more likely to have undifferentiated rather than well-differentiated tumors (odds ratio [OR], 1.23; 95% confidence interval [95% CI], 1.10-1.37), and stage II rather than stage I disease (OR, 1.14; 95% CI, 1.04-1.24). They were also more likely to undergo limb-sparing resection (OR, 1.58; 95% CI, 1.39-1.79) or amputation (OR, 1.72; 95% CI, 1.44-2.07) rather than no surgery and less likely to have positive margins (OR, 0.86; 95% CI, 0.79-0.93). There was no difference in the risk of death between patients who traveled ≥15 miles and those who did not (hazard ratio, 1.00; 95% CI, 0.94-1.07). CONCLUSIONS: Although clinical characteristics and treatments may differ based on distance traveled, survival appears equivalent. Further research into reasons why greater distance traveled is associated with more advanced disease, but comparable survival is warranted.

Impact of Sun Exposure and Tanning Patterns on Next-Generation Sequencing Mutations in Melanoma.

BACKGROUND: For the past 30 y, the incidence rate of malignant melanoma has risen steadily. Ultraviolet radiation exposure has been identified as the most prevalent modifiable risk factor for melanoma. Here, next-generation sequencing was used to analyze the relationship between multiple sun exposure factors and select cancer-related genes to determine the relationship of sun exposure on the molecular profiles of melanomas. METHODS: The collection and analysis of study samples were approved by the institutional review board. The patient cohort consisted of 173 patients whose melanoma tissue samples underwent next-generation sequencing analysis for somatic mutations of 50 cancer-related genes. Univariate and multivariate analyses were conducted. RESULTS: Patients with a history of blistering sunburn had an absolute mutation incidence of 1.67 mutations per patient, compared with patients without a history of blistering sunburn, who had an absolute mutation incidence of 1.16 mutations per patient (P = 0.028). A BRAF mutation was found in more tumors of patients who reported visiting a tanning salon (57.14%), compared with those who had not (18.75%; P = 0.0463). Patients with a previous history of skin cancer were more likely to have a CDKN2A mutation (20.83%), compared with those without a previous history of skin cancer (7.76%; P = 0.0292). CONCLUSIONS: The trends seen in the molecular profiles of melanomas with respect to various sun exposure factors suggest that sun exposure impacts genetic makeup. Considering the increase in absolute mutation incidence in patients with a history of blistering sunburn suggests that additional genes may contribute to the pathology of malignancy. Future studies will use the unique molecular profiles of melanomas to personalize patient treatments.

Low Frequency of Lymph Node Metastases in Patients in the United States With Early-stage Gastric Cancers That Fulfill Japanese Endoscopic Resection Criteria.

BACKGROUND & AIMS: In the West, early gastric cancer is increasingly managed with endoscopic resection (ER). This is, however, based on the assumption that the low prevalence and risk of lymph node metastases observed in Asian patients is applicable to patients in the United States. We sought to evaluate the frequency of and factors associated with metastasis of early gastric cancers to lymph nodes, and whether the Japanese ER criteria are applicable to patients in the US. METHODS: We performed a retrospective study of 176 patients (mean age 68.5 years; 59.1% male; 58.5% white) who underwent surgical resection with lymph node dissection of T1 and Tis gastric adenocarcinomas, staged by pathologists, at 7 tertiary care centers in the US from January 1, 1999, through December 31, 2016. The frequency of lymph node metastases and associated risk factors were determined. RESULTS: The mean size of gastric adenocarcinomas was 23.0 ± 16.6 mm-most were located in the lower-third of the stomach (67.0%), invading the submucosa (55.1%), and moderately differentiated (31.3%). Lymphovascular invasion was observed in 18.2% of lesions. Overall, 20.5% of patients had lymph node metastases. Submucosal invasion (odds ratio, 3.9; 95% CI, 1.4-10.7) and lymphovascular invasion (odds ratio, 4.6; 95% CI, 1.8-12.0) were independently associated with increased risk of metastasis to lymph nodes. The frequency of lymph node metastases among patients fulfilling standard and expanded Japanese criteria for ER were 0 and 7.5%, respectively. CONCLUSIONS: The frequency of lymph node metastases among patients with early gastric cancer in a US population is higher than that of published Asian series. However, early gastric cancer lesions that meet the Japanese standard criteria for ER are associated with negligible risk of metastasis to lymph nodes, so ER can be recommended for definitive therapy. Expanded criteria cancers appear to have a higher risk of metastasis to lymph nodes, so ER may be considered for select cases.

Quarkyonic Matter and Neutron Stars.

We consider quarkyonic matter to naturally explain the observed properties of neutron stars. We argue that such matter might exist at densities close to that of nuclear matter, and at the onset, the pressure and the sound velocity in quarkyonic matter increase rapidly. In the limit of large number of quark colors N_{c}, this transition is characterized by a discontinuous change in pressure as a function of baryon number density. We make a simple model of quarkyonic matter and show that generically the sound velocity is a nonmonotonic function of density-it reaches a maximum at relatively low density, decreases, and then increases again to its asymptotic value of 1/sqrt[3].

Gravitational Waves from Compact Dark Objects in Neutron Stars.

Dark matter could be composed of compact dark objects (CDOs). We find that the oscillation of CDOs inside neutron stars can be a detectable source of gravitational waves (GWs). The GW strain amplitude depends on the mass of the CDO, and its frequency is typically in the range 3-5 kHz as determined by the central density of the star. In the best cases, LIGO may be sensitive to CDO masses greater than or of order 10^{-8} M_{⊙}.