Radical Resection in Entero-Pancreatic Neuroendocrine Tumors: Recurrence-Free Survival Rate and Definition of a Risk Score for Recurrence.

BACKGROUND: Surgery with radical intent is the only potentially curative option for entero-pancreatic neuroendocrine tumors (EP-NETs) but many patients develop recurrence even after many years. The subset of patients at high risk of disease recurrence has not been clearly defined to date. OBJECTIVE: The aim of this retrospective study was to define, in a series of completely resected EP-NETs, the recurrence-free survival (RFS) rate and a risk score for disease recurrence. PATIENTS AND METHODS: This was a multicenter retrospective analysis of sporadic pancreatic NETs (PanNETs) or small intestine NETs (SiNETs) [G1/G2] that underwent R0/R1 surgery (years 2000-2016) with at least a 24-month follow-up. Survival analysis was performed using the Kaplan-Meier method and risk factor analysis was performed using the Cox regression model. RESULTS: Overall, 441 patients (224 PanNETs and 217 SiNETs) were included, with a median Ki67 of 2% in tumor tissue and 8.2% stage IV disease. Median RFS was 101 months (5-year rate 67.9%). The derived prognostic score defined by multivariable analysis included prognostic parameters, such as TNM stage, lymph node ratio, margin status, and grading. The score distinguished three risk categories with a significantly different RFS (p < 0.01). CONCLUSIONS: Approximately 30% of patients with EP-NETs recurred within 5 years after radical surgery. Risk factors for recurrence were disease stage, lymph node ratio, margin status, and grading. The definition of risk categories may help in selecting patients who might benefit from adjuvant treatments and more intensive follow-up programs.

Gastric neuroendocrine neoplasias: manifestations and comparative outcomes.

Although gastric neuroendocrine neoplasias (gNEN) are an orphan disease, their incidence is rising. The heterogeneous clinical course powers the ongoing discussion of the most appropriate classification system and management. Prognostic relevance of proposed classifications was retrospectively analysed in 142 patients from a single tertiary referral centre. Baseline, management and survival data were acquired for statistical analyses. The distribution according to the clinicopathological typification was gNEN-1 (n = 86/60.6%), gNEN-2 (n = 7/4.9%), gNEN-3 (n = 24/16.9%) and gNEN-4 (n = 25/17.6%), while hypergastrinemia-associated gNEN-1 and -2 were all low-grade tumours (NET-G1/2), formerly termed sporadic gNEN-3 could be subdivided into gNEN-3 with grade 1 or 2 and gNEN-4 with grade 3 (NEC-G3). During follow-up 36 patients died (25%). The mean overall survival (OS) of all gNEN was 14.2 years. The OS differed statistically significant across all subgroups with either classification system. According to UICC 2017 TNM classification, OS differed for early and advanced stages, while WHO grading indicated poorer prognosis for NEC-G3. Cox regression analysis confirmed the independent prognostic validity of either classification system for survival. Particularly careful analysis of the clinical course of gNEN-1 (ECLomas, gastric carcinoids) confirmed their mostly benign, but recurrent and extremely slowly progressive behaviour with low risk of metastasis (7%) and an efficient long-term control by repetitive endoscopic procedures. Our study provides evidence for the validity of current classifications focusing on typing, grading and staging. These are crucial tools for risk stratification, especially to differentiate gNEN-1 as well as sporadic gNET and gNEC (gNEN-3 vs -4).

[Endoscopic therapy for gastroduodenal neuroendocrine neoplasms]. / Endoskopische Therapie gastroduodenaler neuroendokriner Neoplasien.

Neuroendocrine neoplasms (NEN) represent a group of potentially malignant tumors, which can be located in every section of the gastrointestinal tract, the pancreas and the bronchopulmonary system. Gastroduodenal NENs have a relatively good prognosis in comparison to other subentities, e.g. pancreatic or ileojejunal NENs. In the stomach there are four different types of NENs, while in the duodenum there are five types and all vary in the malignant potential and the therapeutic approach. Due to the simple access endoscopic methods not only have diagnostic but also important therapeutic relevance in this subgroup. Lesions smaller than 1 cm can easily be resected with forceps or snare resection and for larger lesions up to 2 cm more invasive strategies, such as endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are available. Important criteria in gastric NEN for the risk evaluation of endoscopic treatment alone are the size of the lesion, depth of invasion and the tumor biology, e.g. neuroendocrine tumor (NET) G1/G2 versus neuroendocrine carcinoma (NEC) G3. In duodenal NEN the aforementioned risk factors also apply and in addition only lesions outside the ampulla of Vater should be endoscopically resected whereas periampullary lesions need to be addressed surgically. As an individualized therapeutic approach the possibility of a combined endoscopic and laparoscopic resection technique exists. Follow-up endoscopic investigations are necessary, especially in gastric type 1 NENs, which have a tendency to relapse.

A rare cause of peripheral arthralgia in inflammatory bowel disease: multifocal osteonecrosis.

Osteonecrosis (ON) is characterized by an infarction of osseous tissue in the subchondral regions of the bone. We report the case of a young male patient with ulcerative colitis (UC) developing severe and multifocal, large joint ON resulting in severe disability. Since typical symptoms of ON, like joint pain, might be misinterpreted as common extraintestinal manifestations, ON might easily be overlooked in patients with inflammatory bowel disease (IBD). Plain radiographs detect only advanced cases, MRI is the diagnostic method of choice with a specificity and sensitivity of > 90 %. We discuss the incidence of ON specifically in IBD and provide an update on risk factors like treatment with corticosteroids (CS), although ON has been reported in IBD patients without previous CS treatment. Apart from that, underlying inflammation, thromboembolic events and genetic risk factors might be involved in ON development supporting the hypothesis of a complex cascade. Causative therapies for ON are not available, and surgical interventions like trepanning, core decompression and prosthetic replacement are often necessary. Our intention is to direct attention to this severe complication in the differential work-up of joint pain in IBD patients.

[Neuroendocrine neoplasms of the distal jejunum and ileum]. / Neuroendokrine Neoplasien des distalen Jejunums und Ileums.

Neuroendocrine neoplasms (NEN) of the distal jejunum and ileum derive from serotonin-producing enterochromaffin (EC) cells. Due to their low proliferation rate and their infiltrative growth, they are often discovered at an advanced disease stage when metastasis has already occurred. The biology of these tumours is different from other NEN of the digestive tract. In order to standardise and improve diagnosis and therapy, the guidelines for the diagnosis and clinical management of jejuno-ileal NEN as well as for the management of patients with liver and other distant metastases from NEN were revised by the European Neuroendocrine Tumour Society (ENETS) in 2012. This review focuses on aspects relevant for surgical pathology.

Systemic therapeutic strategies for GEP-NETS: what can we expect in the future?

Over the last few years, there have been important advances in the understanding of the molecular biology of neuroendocrine tumors (NETs) that have already translated into relevant advances in the clinic. Several studies have extensively assessed the mutational profile of NETs, and have shown the key roles that angiogenesis and the PI3K-AKT-mTOR pathway play in the pathogenesis of these tumors. Recent data has also revealed the potential relevance of transcription factors such as death domain-associated protein, x-linked mental retardation, and α-thalassemia syndrome protein or ataxia telangiectasia-mutated in NETs of pancreatic origin. This fast progress is leading to a rapidly increasing number of new agents being explored in the field of NETs. However, and despite some unquestionable success, objective remission rates remain low, and evidence of a substantial survival impact is lacking. Thus, there is an important need to improve our ability to identify patients most likely to benefit from specific therapies, and to incorporate biomarkers in the management of NETs. In addition, further efforts to understand mechanisms of escape and acquired resistance to the different available agents is of utmost importance, and will likely require performing paired tumor biopsies (prior and after treatment) or sequential sampling of surrogate tissues. Combinations of approved agents with new agents, either in a rational or biomarker-driven manner, are certainly warranted in this field. Likewise, sequential strategies to modulate and compensate for escape phenomenons are also of great interest. It should also be noted, however, that targeted agents are not innocuous and frequently yield toxicities that need to be adequately addressed by experienced specialists, particularly when drug combinations are considered. This review summarizes the salient data on biomarker and new agent development for the treatment of NETs.

Activation of TRPV4 channel in pancreatic INS-1E beta cells enhances glucose-stimulated insulin secretion via calcium-dependent mechanisms.

Transient receptor potential channel vanilloid type 4 (TRPV4) is a Ca(2+)- and Mg(2+)-permeable cation channel that influences oxidative metabolism and insulin sensitivity. The role of TRPV4 in pancreatic beta cells is largely unknown. Here, we characterize the role of TRPV4 in controlling intracellular Ca(2+) and insulin secretion in INS-1E beta cells. Osmotic, thermal or pharmacological activation of TRPV4 caused a rapid rise of intracellular Ca(2+) and enhanced glucose-stimulated insulin secretion. In the presence of the TRPV channel blocker ruthenium red (RuR) or after suppression of TRPV4 protein production, TRPV4 activators failed to increase [Ca(2+)]i and insulin secretion in INS-1E cells.

Impact of octreotide long-acting release on tumour growth control as a first-line treatment in neuroendocrine tumours of pancreatic origin.

BACKGROUND: Somatostatin analogues (SSA) are widely used in the treatment of patients with functioning and non-functioning neuroendocrine tumours (NET). The aim of our investigation was to evaluate the antiproliferative effect of SSA in patients with pancreatic NET. METHODS: We retrospectively analysed records of 43 patients with pancreatic NET treated at our clinic with octreotide long-lasting release as a first-line therapy. The aim of our study was to investigate the overall best response according to the RECIST criteria, overall best response defined as disease control rate (SD+PR), response and disease control rate at 12 months, and time to tumour progression (TTP). RESULTS: The mean age (± SD) of the patients (16 female/27 male) at initial diagnosis was 54.7 ± 11.86 years. At the start of therapy, 39 of 43 patients were classified as stage IV according to ENETS-TNM. Tumours were graded, based on MiB-1/Ki67 staining, as G1 (n = 8), G2 (n = 30) or unknown (n = 5). The octreoscan was positive in 37 patients, negative in 2 and unknown in 4 cases. Nineteen patients had functioning tumours, 24 patients had non-functioning tumours. Median overall survival was 98 months, and median TTP was 13 months. Analysis of grading showed a statistically significant influence on TTP when comparing the median TTP for Ki67 >10% with Ki67 <5% (p = 0.009) and Ki67 5-10% (p = 0.036). CONCLUSION: SSA may be considered as a first-line treatment for antiproliferative purposes in metastatic NET of the pancreas. Patients with a proliferation index <10% displayed a more durable response compared to those with a higher proliferation index.

Assessment and clinical implications of RANK/RANKL/OPG pathway as markers of bone tumor progression in patients with NET harboring bone metastases.

INTRODUCTION: The impact on the survival of bone metastases (BM) in patients with neuroendocrine tumor (NET) is a matter of debate. BM have a key role in causing symptoms and in decreasing patients' quality of life. Although the mechanisms of the development of BM are not completely clear, it is now well understood that the Receptor Activator of Nuclear factor Kappa-B-/Ligand (RANK/RANKL)/osteoprotegerin (OPG) pathway plays a relevant role. AIM: To characterize the RANK/RANKL/OPG pathway in patients affected with NET. PATIENTS AND METHODS: Two cohorts of 15 patients each were enrolled in the study; one cohort was affected with NET without BM and the second cohort was affected with NET with BM. The serum RANK/RANKL/OPG pathway was assessed in both the groups. RESULTS: Serum OPG levels and RANKL/OPG ratio were lower and higher, respectively, in NET patients harboring BM than in those without BM. During the ROC analysis, a cut-off value of 1071 pg/ml for OPG and 0.62 for RANKL/OPG ratio were able to significantly distinguish between the two groups. CONCLUSIONS: This study indicates that RANK/RANKL/OPG pathway is imbalanced in patients with NET harboring BM. Specific alterations of this pathway could predict an early development of BM.

Glucagon increases circulating fibroblast growth factor 21 independently of endogenous insulin levels: a novel mechanism of glucagon-stimulated lipolysis?

AIMS/HYPOTHESIS: Glucagon reduces body weight by modifying food intake, glucose/lipid metabolism and energy expenditure. All these physiological processes are also controlled by fibroblast growth factor 21 (FGF-21), a circulating hepatokine that improves the metabolic profile in obesity and type 2 diabetes. Animal experiments have suggested a possible interaction between glucagon and FGF-21 however, the metabolic consequences of this crosstalk are not understood. METHODS: The effects of exogenous glucagon on plasma FGF-21 levels and lipolysis were evaluated in healthy volunteers and humans with type 1 diabetes, as well as in rodents with streptozotocin (STZ)-induced insulinopenic diabetes. In vitro, the role of glucagon on FGF-21 secretion and lipolysis was studied using isolated primary rat hepatocytes and adipocytes. Fgf-21 expression in differentiated rat pre-adipocytes was suppressed by small interfering RNA and released FGF-21 was immunoneutralised by polyclonal antibodies. RESULTS: Glucagon induced lipolysis in healthy human volunteers, patients with type 1 diabetes, mice and rats with STZ-induced insulinopenic diabetes, and in adipocytes isolated from diabetic and non-diabetic animals. In addition, glucagon increased circulating FGF-21 in healthy humans and rodents, as well as in patients with type 1 diabetes, and insulinopenic rodents. Glucagon stimulated FGF-21 secretion from isolated primary hepatocytes and adipocytes derived from animals with insulinopenic diabetes. Furthermore, FGF-21 stimulated lipolysis in primary adipocytes isolated from non-diabetic and diabetic rats. Reduction of Fgf-21 expression (by approximately 66%) or immunoneutralisation of released FGF-21 markedly attenuated glucagon-stimulated lipolysis in adipocytes. CONCLUSIONS/INTERPRETATION: These results indicate that glucagon increases circulating FGF-21 independently of endogenous insulin levels. FGF-21 participates in glucagon-induced stimulation of lipolysis.

Effects of orexin A on proliferation, survival, apoptosis and differentiation of 3T3-L1 preadipocytes into mature adipocytes.

Metabolic activities of orexin A (OXA) in mature adipocytes are mediated via PI3K/PKB and PPARγ. However, the effects of OXA on preadipocytes are largely unknown. We report here that OXA stimulates the proliferation and viability of 3T3-L1 preadipocytes and protects them from apoptosis via ERK1/2, but not through PKB. OXA reduces proapoptotic activity of caspase-3 via ERK1/2. Inhibition of ERK1/2 prevents the differentiation of preadipocytes into adipocytes. Unlike insulin, neither short-term nor prolonged exposure of 3T3-L1 preadipocytes to OXA induces preadipocyte differentiation to adipocytes, despite increased ERK1/2 phosphorylation. Unlike insulin, OXA fails to activate PKB, which explains its inability to induce the differentiation of preadipocytes.

[Gastroenteropancreatic neuro-endocrine neoplasms]. / Neuroendokrine Neoplasiendes gastroenteropankreatischen Systems.

Neuroendocrine neoplasms (NEN) occur in the entire gastrointestinal tract. The updated classification of the WHO (2010) and current TNM-classification provide a basis for the therapeutic decision and assess the prognosis. Endoscopy and different imaging techniques are important for the localization of the primary tumor as well as local and distant metastases. The most important diagnostic imaging technique is somatostatin receptor scintigraphy. Therapeutic strategy should be discussed within the scope of a multidisciplinary tumor board. Surgery of NEN is the sole curative option. The treatment options for liver metastases include surgical resection as well as radiofrequency ablation and hepatic artery embolization. In advanced stage, systemic therapy should be used. Recent studies demonstrated a significantly prolonged progression-free survival using octreotide in well differentiated NEN. Besides the well established steptozotocine based chemotherapy regimens for pancreatic NEN, novel agents such as the mTOR-inhibitor everolimus and multityrosine kinase inhibitor sunitinib have recently also shown a prolonged progression-free survival. Moreover, temozolomide-based chemotherapy appears to be effective in pancreatic NEN. Finally, somatostatin receptor targeted radionuclide therapy can be effective in progressing gastroenteropancreatic NEN.

TNM staging of neoplasms of the endocrine pancreas: results from a large international cohort study.

BACKGROUND: Both the European Neuroendocrine Tumor Society (ENETS) and the International Union for Cancer Control/American Joint Cancer Committee/World Health Organization (UICC/AJCC/WHO) have proposed TNM staging systems for pancreatic neuroendocrine neoplasms. This study aims to identify the most accurate and useful TNM system for pancreatic neuroendocrine neoplasms. METHODS: The study included 1072 patients who had undergone previous surgery for their cancer and for which at least 2 years of follow-up from 1990 to 2007 was available. Data on 28 variables were collected, and the performance of the two TNM staging systems was compared by Cox regression analysis and multivariable analyses. All statistical tests were two-sided. RESULTS: Differences in distribution of sex and age were observed for the ENETS TNM staging system. At Cox regression analysis, only the ENETS TNM staging system perfectly allocated patients into four statistically significantly different and equally populated risk groups (with stage I as the reference; stage II hazard ratio [HR] of death = 16.23, 95% confidence interval [CI] = 2.14 to 123, P = .007; stage III HR of death = 51.81, 95% CI = 7.11 to 377, P < .001; and stage IV HR of death = 160, 95% CI = 22.30 to 1143, P < .001). However, the UICC/AJCC/WHO 2010 TNM staging system compressed the disease into three differently populated classes, with most patients in stage I, and with the patients being equally distributed into stages II-III (statistically similar) and IV (with stage I as the reference; stage II HR of death = 9.57, 95% CI = 4.62 to 19.88, P < .001; stage III HR of death = 9.32, 95% CI = 3.69 to 23.53, P = .94; and stage IV HR of death = 30.84, 95% CI = 15.62 to 60.87, P < .001). Multivariable modeling indicated curative surgery, TNM staging, and grading were effective predictors of death, and grading was the second most effective independent predictor of survival in the absence of staging information. Though both TNM staging systems were independent predictors of survival, the UICC/AJCC/WHO 2010 TNM stages showed very large 95% confidence intervals for each stage, indicating an inaccurate predictive ability. CONCLUSION: Our data suggest the ENETS TNM staging system is superior to the UICC/AJCC/WHO 2010 TNM staging system and supports its use in clinical practice.

The proline TP53 variant stimulates likely lymphangiogenesis in an orthotopic mouse model of pancreatic cancer.

BACKGROUND: Pancreatic cancer is a deadly disease characterised by high incidence of TP53 mutations. Restoration of TP53 function is perceived as a highly attractive therapeutic strategy, whose effects are not well characterised. METHODS: The current work adapted an inducible strategy of stage-specific reexpression of wild-type (wt) TP53 in an in vivo orthotopic mouse model of pancreatic cancer. RESULTS: The reconstitution of wt TP53 function in TP53-mutant DanG and MiaPaCa-2 cells caused G1 cell cycle arrest but no evidence of apoptosis induction. Consistent with subcutaneous xenograft models, we found that wt TP53 reduced primary tumour growth. Wt TP53 reexpression during early tumour growth led to significant increase in vascularisation. This correlated with an unexpectedly high rate of micro-metastases in lymph nodes of animals with wt TP53 induction, despite the 90% decrease in median primary tumour weight. Reexpression of wt TP53 later in tumour development did not significantly affect the number of CD31-reactive vessels, but increased lymphatic vessel density. CONCLUSION: The increased number of lymphatic vessels and micro-metastases suggests that wt TP53 induction complexly affected the biology of different tumour constituents of pancreatic cancer. Our observation suggests that combination of the inducible system with an orthotopic model can yield important insights into in vivo pancreatic cancer biology.

Novel therapeutic agents for the treatment of gastroenteropancreatic neuroendocrine tumors.

Neuroendocrine tumors (NET) are frequently diagnosed late and not amenable to curative surgery due to metastatic disease to the liver and lymph nodes. The disease is complex and heterogeneous given the various functionalities, distinct tumor growth patterns, and tumor spread upon diagnosis. Established therapies include somatostatin analogues, alpha-interferon, systemic chemotherapy, and loco-regional therapies of the liver. The availability of novel agents and expression of targets, such as growth factor receptors, different subtypes of somatostatin receptors, and the mammalian target of rapamycin (mTOR) have led to the exploration of different classes of drugs and offer new treatment opportunities in neuroendocrine tumors. This review provides an overview on novel drugs, focus on the impact of recently approved drugs on the management of NET disease, and outline future perspectives.

Management and outcomes of haemorrhage after pancreatogastrostomy versus pancreatojejunostomy.

BACKGROUND: Postpancreatectomy haemorrhage (PPH) is a major cause of morbidity and mortality after pancreaticoduodenectomy (PD). It remains unclear whether performance of a pancreatogastrostomy (PG) instead of a pancreatojejunostomy (PJ) improves outcomes owing to better endoscopic accessibility. METHODS: A large retrospective analysis was undertaken to compare outcomes of PPH, depending on whether a PG or PJ was performed. The primary outcome was the rate of successful endoscopy. A secondary outcome was the therapeutic success after adding surgery. RESULTS: Of 944 patients who had a PD, 8·4 per cent developed PPH. Endoscopy was the primary intervention in 21 (81 per cent) of 26 patients with a PG and 34 (64 per cent) of 53 with a PJ; it identified the bleeding site in 35 and 25 per cent respectively (P = 0·347). Successful endoscopic treatment was more common in the PG group (31 versus 9 per cent; P = 0·026). Surgery was performed for PPH in 15 patients (58 per cent) with a PG and 35 (66 per cent) with a PJ (P = 0·470). The majority of haemorrhages that required surgery were non-anastomotic intra-abdominal haemorrhages (12 of 15 versus 21 of 35; P = 0·171). Endoscopic or conservative treatment for PPH was successful in 42 per cent of patients with a PG and 32 per cent with a PJ (P = 0·520). The success rate increased to 85 and 91 per cent respectively when surgery was included in the algorithm (P = 0·467). CONCLUSION: The type of pancreatic anastomosis and its inherent effect on endoscopic accessibility had very little impact on the outcome of PPH. This was because haemorrhage frequently occurred from intra-abdominal or non-anastomotic intraluminal lesions.

CD154, a marker of antigen-specific stimulation of CD4 T cells, is associated with response to treatment in patients with chronic HCV infection.

CD4 T-cell function is crucial for the eradication of HCV, and insufficient function is observed in chronic carriers. The monitoring of T-cell responses is complicated by the scarcity of antigen-specific T cells and the relative inefficiency of virus-specific T cells to produce effector cytokines. CD154 is a marker of activation expressed on T cells induced through their T-cell receptor. We analysed CD4 T-cell responses in 72 patients with chronic or resolved HCV infection (23 treatment naïve, 49 treatment experienced, including 16 who had achieved a sustained response). In an additional prospective protocol, 20 of the chronically infected patients were analysed before and after 8-12 weeks of combination therapy with peg-interferon-α and ribavirin. T-cell responses were measured by detecting the expression of CD154 and Th1 cytokines after stimulation with recombinant HCV proteins and were correlated with pretreatment status and outcome of therapy. Broader T-cell responses were observed in treatment naïve than in experienced patients, while the outcome of a preceding therapy regimen did not influence T-cell responses. In the prospective cohort, an on-treatment increase in CD154+ cytokine- T-cell activity was associated with response to treatment, while a decrease was observed in nonresponders. Stronger antigen-independent activity of CD154+ cytokine+ T cells was observed in responders than in nonresponders. Our data indicate that CD154 as a marker of activation of CD4 T cells is a suitable tool for the analysis of T-cell responses in patients with HCV infection.