Endoscopic papillectomy for ampullary lesions of minor papilla.

BACKGROUND AND AIMS: Ampullary lesions (ALs) of the minor duodenal papilla are extremely rare. Endoscopic papillectomy (EP) is a routinely used treatment for AL of the major duodenal papilla, but the role of EP for minor AL has not been accurately studied. METHODS: We identified 20 patients with ALs of minor duodenal papilla in the multicentric database from the Endoscopic Papillectomy vs Surgical Ampullectomy vs Pancreatitcoduodenectomy for Ampullary Neoplasm study, which included 1422 EPs. We used propensity score matching (nearest-neighbor method) to match these cases with ALs of the major duodenal papilla based on age, sex, histologic subtype, and size of the lesion in a 1:2 ratio. Cohorts were compared by means of chi-square or Fisher exact test as well as Mann-Whitney U test. RESULTS: Propensity score-based matching identified a cohort of 60 (minor papilla 20, major papilla 40) patients with similar baseline characteristics. The most common histologic subtype of lesions of minor papilla was an ampullary adenoma in 12 patients (3 low-grade dysplasia and 9 high-grade dysplasia). Five patients revealed nonneoplastic lesions. Invasive cancer (T1a), adenomyoma, and neuroendocrine neoplasia were each found in 1 case. The rate of complete resection, en-bloc resection, and recurrences were similar between the groups. There were no severe adverse events after EP of lesions of minor papilla. One patient had delayed bleeding that could be treated by endoscopic hemostasis, and 2 patients showed a recurrence in surveillance endoscopy after a median follow-up of 21 months (interquartile range, 12-50 months). CONCLUSIONS: EP is safe and effective in ALs of the minor duodenal papilla. Such lesions could be managed according to guidelines for EP of major duodenal papilla.

Body composition parameters predict survival in pancreatic cancer-A retrospective multicenter analysis.

BACKGROUND: Parameters to adapt individual treatment strategies for patients with pancreatic ductal adenocarcinoma (PDAC) are urgently needed. The present study aimed to evaluate body composition parameters as predictors of overall survival (OS) in PDAC patients. METHODS: Measurements of body composition parameters were performed on computed tomography scans at diagnosis. Height-standardized and Body Mass Index- and sex-adjusted regression formulas deriving cut-offs from a healthy population were used. The Kaplan-Meier method with the log-rank test was performed for survival analysis. Independent prognostic factors were identified with uni- and multivariable Cox regression analyses. RESULTS: In total, 354 patients were analyzed. In a multivariable Cox model, besides tumor stage and resection status, only myosteatosis (HR 1.53; 95% CI 1.10-2.14, p = 0.01) was an independent prognostic factor of OS among body composition parameters. Subgroup analyses revealed that the prognostic impact of myosteatosis was higher in patients ≤68 years of age, with advanced tumor stages and patients without curative intended resection. CONCLUSIONS: The analysis of one of the largest Caucasian cohorts to date, demonstrated myosteatosis to be an independent prognostic factor of OS in PDAC. To improve outcomes, prospective trials aiming to investigate the utility of an early assessment of myosteatosis with subsequent intervention by dieticians, sports medicine physicians, and physiotherapists are warranted.

Treatment of esophageal leakages with the Microtech®-VAC-Stent: a monocentric early experience of three cases.

Background: Endoscopic approaches in the treatment of transmural esophageal defects, either after esophageal resection or due to perforation, have demonstrated convincing feasibility. Surgical options are limited and associated with high morbidity and mortality rates. Currently, internal endoscopic drainage with pigtail stents, self-expanding metal stent (SEMS), or endoscopic vacuum therapy (EVT) are options for first-line treatment. Here, we report the outcome of the recently developed combination of SEMS and EVT using the endoscopic Microtech®-VAC-Stent (EVS). Methods: Between June and July 2022, three consecutive patients (one female and two males) with esophageal transmural defects were treated with the Microtech®-VAC-Stent. Two patients suffered from an anastomotic leak after oncologic gastroesophageal surgery, and one patient presented with esophageal perforation due to Boerhaave syndrome. Results: Three consecutive patients were successfully treated with EVS. In one patient, one EVS treatment was sufficient, whereas the other two patients needed two and six EVS exchanges. Exchanges were scheduled every 7 days and no procedural adverse events were observed. Conclusion: In line with the former case series, EVS therapy is a promising new approach for the treatment of esophageal leaks. Exchange of the EVS seems feasible every 7 days reducing interventions for the individual patient. Prospective studies comparing EVS with other endoscopic therapies are needed to define the best therapeutic approach.

Anti-angiogenic therapy using the multi-tyrosine kinase inhibitor Regorafenib enhances tumor progression in a transgenic mouse model of ß-cell carcinogenesis.

BACKGROUND: Pancreatic neuroendocrine tumors (PNETs) represent a distinct hypervascularized tumor entity, often diagnosed at metastatic stage. Therapeutic efficacy of anti-angiogenic multi-kinase inhibitors is frequently limited by primary or acquired resistance in vivo. This study aimed to characterize the molecular mode of action as well as resistance mechanisms to the anti-angiogenic multi-tyrosine kinase inhibitor (TKI) Regorafenib in vitro and in vivo. METHODS: In vitro, human and murine pancreatic neuroendocrine cell lines were comparatively treated with Regorafenib and other TKIs clinically used in PNETs. Effects on cell viability and proliferation were analyzed. In vivo, transgenic RIP1Tag2 mice were treated with Regorafenib at two different time periods during carcinogenesis and its impact on angiogenesis and tumor progression was evaluated. RESULTS: Compared to the established TKI therapies with Sunitinib and Everolimus, Regorafenib showed the strongest effects on cell viability and proliferation in vitro, but was unable to induce apoptosis. Unexpectedly and in contrast to these in vitro findings, Regorafenib enhanced proliferation during early tumor development in RIP1Tag2 mice and had no significant effect in late tumor progression. In addition, invasiveness was increased at both time points. Mechanistically, we could identify an upregulation of the pro-survival protein Bcl-2, the induction of the COX2-PGE2-pathway as well as the infiltration of CSF1R positive immune cells into the tumors as potential resistance mechanisms following Regorafenib treatment. DISCUSSION: Our data identify important tumor cell-autonomous and stroma-dependent mechanisms of resistance to antiangiogenic therapies.

Gender-specific changes of the gut microbiome correlate with tumor development in murine models of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a dismal outcome. To improve understanding of sequential microbiome changes during PDAC development we analyzed mouse models of pancreatic carcinogenesis (KC mice recapitulating pre-invasive PanIN formation, as well as KPC mice recapitulating invasive PDAC) during early tumor development and subsequent tumor progression. Diversity and community composition were analyzed depending on genotype, age, and gender. Both mouse models demonstrated concordant abundance changes of several genera influenced by one or more of the investigated factors. Abundance was significantly impacted by gender, highlighting the need to further elucidate the impact of gender differences. The findings underline the importance of the microbiome in PDAC development and indicate that microbiological screening of patients at risk and targeting the microbiome in PDAC development may be feasible in future.

Atezolizumab Plus Bevacizumab in Patients with Advanced and Progressing Hepatocellular Carcinoma: Retrospective Multicenter Experience.

Atezolizumab plus bevacizumab is the standard of care for first-line systemic therapy for advanced hepatocellular carcinoma (aHCC). Data on the efficacy and safety of atezolizumab plus bevacizumab in patients with aHCC who have received prior systemic therapy are not available. Methods: Patients with aHCC who received atezolizumab plus bevacizumab after at least one systemic treatment between December 2018 and March 2022 were retrospectively identified in 13 centers in Germany and Austria. Patient characteristics, tumor response rates, progression-free survival (PFS), overall survival (OS), and adverse events (AE) were analyzed. Results: A total of 50 patients were identified; 41 (82%) were male. The median age at initiation of treatment with atezolizumab plus bevacizumab was 65 years, 41 (82%) patients had cirrhosis, 30 (73%) Child A, 9 (22%) B, and 2 (5%) C. A total of 34 patients (68%) received atezolizumab plus bevacizumab in the second-line setting and 16 (32%) in later lines. The best radiologic tumor responses were complete remission (2%), partial remission (30%), stable disease (36%), and progressive disease (18%), resulting in an objective response rate of 32% and a disease control rate of 68%. Median OS was 16.0 months (95% confidence interval 5.6-26.4 months), and median PFS was 7.1 months (95% confidence interval 4.4-9.8 months). AE grades 3-4 were observed in seven (14%) and resulted in death in three patients (6%). There were five (10%) bleeding events with a grade ≥ 3, including one (2%) with a fatal outcome. Conclusions: Atezolizumab plus bevacizumab is effective in patients with aHCC who did not have access to this option as first-line therapy. The safety profile was consistent with previous reports.

Postoperative Sigmoidoscopy and Biopsy After Elective Endovascular and Open Aortic Surgery for Preventing Mortality by Colonic Ischemia (PSB-Aorta-CI): Protocol for a Prospective Study.

BACKGROUND: Endovascular aortic repair is considered the standard procedure in treating patients diagnosed with pathologies of the abdominal aorta with suitable anatomy. Open surgery remains an option mostly for patients not suitable for endovascular surgery. Colonic ischemia is an important and life-threatening postoperative complication of these procedures. OBJECTIVE: The aim of this study is to evaluate the clinical value and safety of performing a planned sigmoidoscopy and biopsy for detection of colonic ischemia in patients undergoing elective aortic surgery. We also aim to develop prediction scores which could identify patients at risk for colonic ischemia and facilitate their timely treatment. METHODS: The trial is designed as a prospective study. The decision for aortic surgery and eligibility for these procedures will be ascertained according to current guidelines. Afterward, screening of the patient for the remaining inclusion and exclusion criteria will occur. If eligibility for study inclusion is confirmed, the patient will be informed about the aims of the study and all study-specific procedures (sigmoidoscopy and biopsy) and asked to provide informed consent. RESULTS: The primary end point is the proportion of patients diagnosed endoscopically with subclinical and clinically relevant colonic ischemia among all patients undergoing aortic surgery. Patient recruitment started on June 2021. The final patient is expected to be treated by the end of June 2023. Institutional Review Board review has been completed at the University of Halle (Saale; reference #052-2021). CONCLUSIONS: this shows that sigmoidoscopy can be performed safely and is effective for the timely diagnosis of colonic ischemia in these patients, this could result in its routine implementation in both elective and emergency settings. TRIAL REGISTRATION: German Clinical Trials Register DRKS00025587; https://www.drks.de/drks_web/navigate.do?navigationId =trial.HTML&TRIAL_ID=DRKS00025587. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/39071.

Updates on Diagnostic and Therapeutic Management of Gastrointestinal and Pancreatic NET.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) comprise a plethora of distinct molecular-pathological, clinical, diagnostical and therapeutical approaches to enable individualized treatment [...].

Colocalization analysis of pancreas eQTLs with risk loci from alcoholic and novel non-alcoholic chronic pancreatitis GWAS suggests potential disease causing mechanisms.

BACKGROUND: Previous genome-wide association studies (GWAS) identified genome-wide significant risk loci in chronic pancreatitis and investigated underlying disease causing mechanisms by simple overlaps with expression quantitative trait loci (eQTLs), a procedure which may often result in false positive conclusions. METHODS: We conducted a GWAS in 584 non-alcoholic chronic pancreatitis (NACP) patients and 6040 healthy controls. Next, we applied Bayesian colocalization analysis of identified genome-wide significant risk loci from both, our recently published alcoholic chronic pancreatitis (ACP) and the novel NACP dataset, with pancreas eQTLs from the GTEx V8 European cohort to prioritize candidate causal genes and extracted credible sets of shared causal variants. RESULTS: Variants at the CTRC (p = 1.22 × 10-21) and SPINK1 (p = 6.59 × 10-47) risk loci reached genome-wide significance in NACP. CTRC risk variants colocalized with CTRC eQTLs in ACP (PP4 = 0.99, PP4/PP3 = 95.51) and NACP (PP4 = 0.99, PP4/PP3 = 95.46). For both diseases, the 95% credible set of shared causal variants consisted of rs497078 and rs545634. CLDN2-MORC4 risk variants colocalized with CLDN2 eQTLs in ACP (PP4 = 0.98, PP4/PP3 = 42.20) and NACP (PP4 = 0.67, PP4/PP3 = 7.18), probably driven by the shared causal variant rs12688220. CONCLUSIONS: A shared causal CTRC risk variant might unfold its pathogenic effect in ACP and NACP by reducing CTRC expression, while the CLDN2-MORC4 shared causal variant rs12688220 may modify ACP and NACP risk by increasing CLDN2 expression.

The Patient's Point of View: COVID-19 and Neuroendocrine Tumor Disease.

The assessment of cancer patient care during the COVID-19 pandemic has been mainly reported from a physician's perspective. Patients with rare tumor entities such as neuroendocrine tumors (NET), which require a complex and specialized care infrastructure, were highly affected by the COVID-19 crisis. Using a structured questionnaire consisting of a general section on the disease and a special COVID-19 section to record medical care, vaccination behavior as well as social and psycho-emotional parameters were collected from NET patients. The survey was distributed via direct medical contact and via the patient organization NETZWERK NeT. A total of 684 patients participated in the survey and 79.2% (n = 542) of the participants answered the questionnaire completely (54 questions). Patient characteristics were comparable to those in large NET registries. The majority of participants were patients with pancreatic and small bowel NET on somatostatin analogue (SSA) therapy. Medical care under COVID-19 was adequate and appointment cancellations and postponements were not common. Nevertheless, the majority of patients were worried about adequate treatment for their tumor disease during the crisis. Most of the participants considered themselves to be at risk of severe COVID-19 infection and were therefore very concerned. This was accompanied by an extremely high vaccination readiness rate of 90%. Increased distress in the social and psycho-emotional domains in the course of the crisis reflected a need for optimization in the medical care of NET patients, although the rate of COVID-19 positive participants was low (3.7%). Therefore, patient-reported measurements are required to identify and address all areas of medical care. Overall, our survey provides an essential contribution to the care of NET patients during the COVID-19 pandemic from the patient's perspective.

The impact of atezolizumab and bevacizumab in hepatocellular carcinoma with activated ß-catenin signaling.

BACKGROUND: To date, no biomarkers exist to predict response or resistance to immunotherapy in hepatocellular carcinoma (HCC). Recent approaches to classify HCC into different immunological states revealed a negative correlation between Wnt/ß-catenin activation and immunogenicity and T-cell infiltration. If these "cold" tumors with primary resistance to checkpoint inhibition (CPI) may benefit from dual treatment of CPI and anti-angiogenic therapy has not been proved. CASE: Here, we describe the case of a male patient with metastatic HCC. After failure of standard of care treatment with lenvatinib, sorafenib and ramucirumab fourth-line systemic therapy with atezolizumab and bevacizumab were applied leading to a phenomenal response. Immunohistochemical evaluations were compatible with Wnt/ß-catenin pathway activation and accompanying low T-cell infiltration as well as low PD-L1 score. CONCLUSION: Patients with Wnt/ß-catenin activation may benefit from combination therapy with atezolizumab and bevacizumab regardless of potential predictive markers for immune checkpoint inhibition.

Ramucirumab in combination with dacarbazine in patients with progressive well-differentiated metastatic pancreatic neuroendocrine tumors (RamuNET): study protocol for a multicenter single-arm trial.

BACKGROUND: Cytotoxic chemotherapy combinations and targeted agents represent established treatment concepts in advanced pancreatic neuroendocrine tumors (PNETs). However, response rates, side effects and outcome data strongly vary among these therapeutic approaches. Head-to-head comparisons between chemo- and molecular therapies are missing and secondary resistances frequently occur. The RamuNET trial aims to identify the effectiveness of dual treatment with DTIC and ramucirumab in progressive advanced PNET patients. METHODS: The RamuNET study is an investigator-initiated multicenter prospective single-arm trial to evaluate the efficacy of ramucirumab in combination with dacarbazine (DTIC) over a period of at least 6 months. Patients with progressive well-differentiated and metastatic pancreatic neuroendocrine tumors are eligible. The study aims to include 45 patients over a period of 24 months with a minimum follow-up of 24 months. The primary endpoint is disease control after 6 months. Secondary endpoints include progression-free survival, biochemical response, overall survival, quality of life and toxicity. Based on the hypothesis that 80% of the patients can achieve a disease control after 6 months, the sample size calculation follows an exact binomial single-stage design. H0: p < =p0 = 60% versus H1: p > =p1 = 80%, alpha = 0.05, beta = 0.1. DISCUSSION: This study investigates a new therapeutic approach using the combination of cytotoxic and targeted antiangiogenic therapy in advanced PNET. If positive, this trial will be the basis for a randomized two-arm study to investigate the combination of ramucirumab and DTIC against other established therapies in PNET. TRIAL REGISTRATION: EudraCT: 2017-001207-68 . Date of registration: 2018.01.03.

Multicenter Analysis of Presacral Neuroendocrine Neoplasms-Clinicopathological Characterization and Treatment Outcomes of a Rare Disease.

Background and Aims: Neuroendocrine neoplasms (NENs) of the presacral space are an extremely rare disease entity with largely unknown outcome and no established standard of care treatment. Therefore, we wanted to analyze clinical presentation, histopathological findings, treatment outcomes, and prognosis in a multicentric patient cohort. Methods: We searched local databases of six German NEN centers for patients with presacral NEN. Retrospective descriptive analyses of age, sex, stage at diagnosis, symptoms, grade, immunohistochemical investigations, biomarkers, treatment, and treatment outcome were performed. Kaplan-Meier analysis was used to determine median overall survival. Results: We identified 17 patients (11 female, 6 male) with a median age of 50 years (range, 35-66) at diagnosis. Twelve cases presented initially with distant metastases including bone metastases in nine cases. On pathological review the majority of patients had well-differentiated G2 tumors. Immunohistochemical profile resembled rectal NENs. All but one patient had non-functioning tumors. Somatostatin receptor imaging was positive in 14 of 15 investigated cases. Eight patients were treated surgically including palliative resections; 14 patients received somatostatin analogs with limited efficacy. With 14 PRRTs completed, 79% showed clinical benefit, whereas only one patient with neuroendocrine carcinoma (NEC) responded to chemotherapy. Treatment with everolimus in three patients was not successful, whereas cabozantinib resulted in a disease stabilization in a heavily pretreated patient. During a median observation period of 44.5 months, 6 patients died. Median overall survival was not reached. Conclusion: Presacral NEN are histopathologically similar to rectal NENs. Presacral NEN should be considered as possible primary in NEN of unknown primary. The majority of tumors is non-functioning and somatostatin receptor positive. PRRT demonstrated promising activity; tyrosine kinase inhibitors warrant further investigations. Further molecular characterization and prospective evaluation of this rare tumor entity are needed.

Efficacy and Safety of Neoadjuvant Gemcitabine Plus Nab-Paclitaxel in Borderline Resectable and Locally Advanced Pancreatic Cancer-A Systematic Review and Meta-Analysis.

Therapy with gemcitabine and nab-paclitaxel (GNP) is the most commonly used palliative chemotherapy, but its advantage in the neoadjuvant setting remains unclear. Accordingly, our aim is to evaluate the impact of first-line neoadjuvant therapy with GNP in patients with borderline resectable (BRPC) and locally advanced pancreatic cancer (LAPC). A systematic search for published studies until August 2020 was performed. The primary endpoint included resection and R0 resection rates in the intention-to-treat population. Secondary endpoints were response rate, survival and toxicity. Among 21 studies, 950 patients who received neoadjuvant GNP were evaluated. Treatment with GNP resulted in surgical resection and R0 resection rates as follows: 49% (95% CI 30-68%) and 36% (95% CI 17-58%) for BRPC and 16% (95% CI 7-26%) and 11% (95% CI 5-19%) for LAPC, respectively. The objective response rates and the median overall survival (mOS) ranged from 0 to 67% and 12 to 30 months, respectively. Neutropenia (range 5-77%) and neuropathy (range 0-22%) were the most commonly reported grade 3 to 4 adverse events. Neoadjuvant chemotherapy with GNP can be performed safely and with valuable effects in patients with BRPC and LAPC. The utility of GNP in comparison to FOLFIRINOX in the neoadjuvant setting requires further investigation in prospective randomized trials.

Targeting HDACs in Pancreatic Neuroendocrine Tumor Models.

Compared to pancreatic adenocarcinoma (PDAC), pancreatic neuroendocrine tumors (PanNET) represent a rare and heterogeneous tumor entity. In addition to surgical resection, several therapeutic approaches, including biotherapy, targeted therapy or chemotherapy are applicable. However, primary or secondary resistance to current therapies is still challenging. Recent genome-wide sequencing efforts in PanNET identified a large number of mutations in pathways involved in epigenetic modulation, including acetylation. Therefore, targeting epigenetic modulators in neuroendocrine cells could represent a new therapeutic avenue. Detailed information on functional effects and affected signaling pathways upon epigenetic targeting in PanNETs, however, is missing. The primary human PanNET cells NT-3 and NT-18 as well as the murine insulinoma cell lines beta-TC-6 (mouse) and RIN-T3 (rat) were treated with the non-selective histone-deacetylase (HDAC) inhibitor panobinostat (PB) and analyzed for functional effects and affected signaling pathways by performing Western blot, FACS and qPCR analyses. Additionally, NanoString analysis of more than 500 potentially affected targets was performed. In vivo immunohistochemistry (IHC) analyses on tumor samples from xenografts and the transgenic neuroendocrine Rip1Tag2-mouse model were investigated. PB dose dependently induced cell cycle arrest and apoptosis in neuroendocrine cells in human and murine species. HDAC inhibition stimulated redifferentiation of human primary PanNET cells by increasing mRNA-expression of somatostatin receptors (SSTRs) and insulin production. In addition to hyperacetylation of known targets, PB mediated pleitropic effects via targeting genes involved in the cell cycle and modulation of the JAK2/STAT3 axis. The HDAC subtypes are expressed ubiquitously in the existing cell models and in human samples of metastatic PanNET. Our results uncover epigenetic HDAC modulation using PB as a promising new therapeutic avenue in PanNET, linking cell-cycle modulation and pathways such as JAK2/STAT3 to epigenetic targeting. Based on our data demonstrating a significant impact of HDAC inhibition in clinical relevant in vitro models, further validation in vivo is warranted.