Approaches for the treatment of perforated peptic ulcers: a network meta-analysis of randomised controlled trials - study protocol.

INTRODUCTION: Perforated peptic ulcers are a life-threatening complication associated with high morbidity and mortality. Several treatment approaches are available. The aim of this network meta-analysis (NMA) is to compare surgical and alternative approaches for the treatment of perforated peptic ulcers regarding mortality and other patient-relevant outcomes. METHODS AND ANALYSIS: A systematic literature search of PubMed/MEDLINE, Cochrane Library, Embase, CINAHL, ClinicalTrials.gov trial registry and ICTRP will be conducted with predefined search terms.To address the question of the most effective treatment approach, an NMA will be performed for each of the outcomes mentioned above. A closed network of interventions is expected. The standardised mean difference with its 95% CI will be used as the effect measure for the continuous outcomes, and the ORs with 95% CI will be calculated for the binary outcomes. ETHICS AND DISSEMINATION: In accordance with the nature of the data used in this meta-analysis, which involves aggregate information from previously published studies ethical approval is deemed unnecessary. Results will be disseminated directly to decision-makers (eg, surgeons, gastroenterologists) through publication in peer-reviewed journals and presentation at conferences. PROSPERO REGISTRATION NUMBER: CRD42023482932.

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.

A Systematic Review and Meta-Analysis of Surgery for Retroperitoneal Sarcoma With Vascular Resection.

This meta-analysis examines the outcomes of patients undergoing surgery with vascular resection for retroperitoneal sarcoma. A systematic literature search based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was conducted, identifying five comparative retrospective cohort studies published from 2015 to 2021, with a total of 1,417 patients (180 in the vascular resection (VR) group and 1,237 in the control (no VR) group). The meta-analysis found that 30-day morbidity rates, as classified by Clavien-Dindo classification > 3, were higher in the VR group compared to the no VR group (46% versus 25%, odds ratio (OR): 1.84, 95% confidence interval (CI): 0.39-8.69, p=0.44). Local recurrence rates during the follow-up period were similar between the two groups (30% versus 30%, OR: 1.46, 95% CI: 0.50-4.25, p=0.49). However, distant recurrence was more frequent in the VR group (32% versus 8.5%, OR: 2.54, 95% CI: 1.05-6.13, p=0.04). In conclusion, although oncovascular procedures are feasible for patients with retroperitoneal sarcomas, the long-term outcomes appear to be worse when compared to procedures that do not involve vessel resections.

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.

Pre-operative/Neoadjuvant Therapy and Vascular Debranching Followed by Resection for Locally Advanced Pancreatic Cancer (PREVADER): Clinical Feasibility Trial.

Introduction: Pancreatic cancer continues to have a poor outcome. Many patients are diagnosed with advanced disease, and in a considerable proportion, abutment or invasion of visceral arteries is present. Moreover, some patients have anatomical variations or stenosis of major visceral arteries requiring arterial reconstruction upon pancreatic cancer resection to avoid organ ischemia. Simultaneous arterial reconstruction during resection is associated with relevant morbidity and mortality. This trial evaluates the approach of visceral debranching, that is, arterial reconstruction, prior to neoadjuvant chemotherapy and tumor resection in patients with locally advanced, unresectable pancreatic cancer. Methods and Analysis: The trial includes patients with locally advanced, non-metastatic pancreatic cancer with arterial abutment or invasion (deemed primarily unresectable), variations in vascular anatomy, or stenosis of visceral arteries. The participants undergo visceral debranching, followed by current standard neoadjuvant chemotherapy (mFOLFIRINOX, gemcitabine-nab-paclitaxel, or other) and potential subsequent tumor resection. The primary outcome is feasibility, measured as the proportion of patients who start neoadjuvant therapy within 6 weeks of visceral debranching. The trial has an exact single-stage design. The proportion below which the treatment is considered ineffective is set at 0.7 (H0). The proportion above which the treatment warrants further exploration in a phase III trial is set at 0.9 (H1). With a power (1-beta) of 0.8 and a type 1 mistake (alpha) of 0.05, the required sample size is 28 patients. Feasibility of the approach will be assumed if 24 of the enrolled 28 patients proceed to neoadjuvant chemotherapy within 6 weeks from visceral debranching. Discussion: This trial evaluates a new treatment sequence, that is, visceral debranching followed by chemotherapy and resection, for pancreatic cancer with invasion or abutment of visceral arteries. The primary objective of the trial is to evaluate feasibility. Trial results will allow for estimating treatment effects and calculating the sample size of a randomized controlled trial, in which the approach will be tested if the feasibility endpoint is met. Clinical Trial Registration: clinicaltrials.gov, identifier: NCT04136769.

Value of diffusion-weighted MR imaging in the diagnosis of lymph node metastases in patients with cholangiocarcinoma.

PURPOSE: To evaluate diffusion-weighted MR imaging (DWI) in the diagnosis of lymph node metastases in patients with cholangiocarcinoma. METHODS: In 24 patients with cholangiocarcinoma, MR imaging of the upper abdomen was performed prior to surgery at 1.5 T using a respiratory-triggered single-shot echo-planar imaging (SSEPI) sequence (b values: 50, 300, and 600 s/mm(2)). ADC (apparent diffusion coefficient) values and diameters of regional lymph nodes (LN) were determined. Subsequently, in all patients, surgical exploration and/or resection of the primary tumor and regional LN dissection were performed. Imaging results were correlated with results of histopathologic analysis. ADC values and diameters of benign and malignant LN were compared using the Mann-Whitney U test. In addition, a ROC (receiver operating characteristic curve) analysis was performed. RESULTS: The mean ADC value (×10(-3) mm(2)/s) of metastatic LN (1.21 ± 0.15) was significantly lower than that of benign LN (1.62 ± 0.33, p < 0.001) while there was no significant difference in the mean diameter of malignant (16.8 ± 5.4 mm) and benign LN (14.1 ± 4.0 mm; p = 0.09). Using an ADC value of 1.25 × 10(-3) mm(2)/s as threshold, 91.4% of LN were correctly classified as benign or malignant with a sensitivity/specificity of 83.3%/92.8% and a positive/negative predictive value of 66.7%/96.7%. The area under the ROC curve was 0.93. CONCLUSION: DWI using a respiratory-triggered SSEPI sequence, according to our preliminary experience, is a promising imaging modality in the differentiation of benign and malignant LN in patients with cholangiocarcinoma.

Inhibition of CD47 Effectively Targets Pancreatic Cancer Stem Cells via Dual Mechanisms.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is a cancer of the exocrine pancreas with unmet medical need and is strongly promoted by tumor-associated macrophages (TAM). The presence of TAMs is associated with poor clinical outcome, and their overall role, therefore, appears to be protumorigenic. The "don't eat me" signal CD47 on cancer cells communicates to the signal regulatory protein-α on macrophages and prevents their phagocytosis. Thus, inhibition of CD47 may offer a new opportunity to turn TAMs against PDAC cells, including cancer stem cells (CSC), as the exclusively tumorigenic population. EXPERIMENTAL DESIGN: We studied in vitro and in vivo the effects of CD47 inhibition on CSCs using a large set of primary pancreatic cancer (stem) cells as well as xenografts of primary human PDAC tissue. RESULTS: CD47 was highly expressed on CSCs, but not on other nonmalignant cells in the pancreas. Targeting CD47 efficiently enhanced phagocytosis of a representative set of primary human pancreatic cancer (stem) cells and, even more intriguingly, also directly induced their apoptosis in the absence of macrophages during long-term inhibition of CD47. In patient-derived xenograft models, CD47 targeting alone did not result in relevant slowing of tumor growth, but the addition of gemcitabine or Abraxane resulted in sustained tumor regression and prevention of disease relapse long after discontinuation of treatment. CONCLUSIONS: These data are consistent with efficient in vivo targeting of CSCs, and strongly suggest that CD47 inhibition could be a novel adjuvant treatment strategy for PDAC independent of underlying and highly variable driver mutations.

Low postoperative platelet count is associated with negative outcome after liver resection for hepatocellular carcinoma.

BACKGROUND/AIMS: Hepatocellular carcinoma is one of the most common malignancies worldwide. The only curative treatment is surgery. As hepatocellular carcinoma is often associated with liver cirrhosis, patients are at risk for postoperative liver failure. In the recent years, platelets are thought to play an important role in liver regeneration.The aim of this study was to discover the relevance of postoperative platelet counts after liver resection for hepatocellular carcinoma. METHODOLOGY: Data of 68 patients who underwent liver resection for hepatocellular carcinoma between July 2007 and July 2012 in a single centre were analysed. Postoperative morbidity and mortality were evaluated in regard to postoperative platelet counts. Comparative analysis between patients with platelet counts ≤100 2x109/ l and >100 x109/ l at d1 was performed in regard to postoperative outcome. RESULTS: Within this cohort, 43 patients (63%) suffered from histologically proven liver cirrhosis. Postoperative mortality was statistically significant associated with postoperative reduced platelet counts. Comparative analysis showed significantly elevated postoperative bilirubin levels and lower prothrombin time in patients with platelet counts ≤ 100 1x109/ l at d1. CONCLUSIONS: Postoperative low platelet counts are associated with poor outcome after hepatic resection for hepatocellular carcinoma.

Intracellular autofluorescence: a biomarker for epithelial cancer stem cells.

Cancer stem cells (CSCs) are thought to drive tumor growth, metastasis and chemoresistance. Although surface markers such as CD133 and CD44 have been successfully used to isolate CSCs, their expression is not exclusively linked to the CSC phenotype and is prone to environmental alteration. We identified cells with an autofluorescent subcellular compartment that exclusively showed CSC features across different human tumor types. Primary tumor-derived autofluorescent cells did not overlap with side-population (SP) cells, were enriched in sphere culture and during chemotherapy, strongly expressed pluripotency-associated genes, were highly metastatic and showed long-term in vivo tumorigenicity, even at the single-cell level. Autofluorescence was due to riboflavin accumulation in membrane-bounded cytoplasmic structures bearing ATP-dependent ABCG2 transporters. In summary, we identified and characterized an intrinsic autofluorescent phenotype in CSCs of diverse epithelial cancers and used this marker to isolate and characterize these cells.

Chloroquine targets pancreatic cancer stem cells via inhibition of CXCR4 and hedgehog signaling.

Pancreatic ductal adenocarcinoma is one of the deadliest carcinomas and is characterized by highly tumorigenic and metastatic cancer stem cells (CSC). CSCs evade available therapies, which preferentially target highly proliferative and more differentiated progenies, leaving behind CSCs as a putative source for disease relapse. Thus, to identify potentially more effective treatment regimens, we screened established and new compounds for their ability to eliminate CSCs in primary pancreatic cancer (stem) cells in vitro and corresponding patient-derived pancreatic cancer tissue xenografts in vivo. Intriguingly, we found that in vitro treatment with the antimalarial agent chloroquine significantly decreased CSCs, translating into diminished in vivo tumorigenicity and invasiveness in a large panel of pancreatic cancers. In vivo treatment in combination with gemcitabine was capable of more effectively eliminating established tumors and improved overall survival. The inhibitory effect of chloroquine was not related to inhibition of autophagy, but was due to inhibition of CXCL12/CXCR4 signaling, resulting in reduced phosphorylation of ERK and STAT3. Furthermore, chloroquine showed potent inhibition of hedgehog signaling by decreasing the production of Smoothened, translating into a significant reduction in sonic hedgehog-induced chemotaxis and downregulation of downstream targets in CSCs and the surrounding stroma. Our study demonstrates that via to date unreported effects, chloroquine is an effective adjuvant therapy to chemotherapy, offering more efficient tumor elimination and improved cure rates. Chloroquine should be further explored in the clinical setting as its success may help to more rapidly improve the poor prognosis of patients with pancreatic cancer.

Interleukin-13 exerts autocrine growth-promoting effects on human pancreatic cancer, and its expression correlates with a propensity for lymph node metastases.

BACKGROUND AND AIMS: Interleukin-13 (IL-13) is an anti-inflammatory cytokine produced in cells of hematopoetic origin. It is not known whether pancreatic cancer cells produce IL-13 or whether IL-13 can modulate pancreatic cancer cell growth and influence the frequency of lymph node metastases. MATERIALS AND METHODS: Cell growth and signaling were analyzed by cell counting, colorimetric proliferation assays, fluorescent-activated cell sorting, and in vitro kinase activity assays. IL-13 expression and secretion were determined by Northern blot analysis and enzyme-linked immunosorbent assay, respectively. Localization of IL-13 and its transmembrane receptor (IL-4R) in primary pancreatic ductal adenocarcinoma (PDAC) was characterized by immunohistochemistry. RESULTS: IL-13 enhanced the growth of ASPC-1, CAPAN-1, and COLO-357 cells. This was associated with enhanced p44/42 mitogen-activated protein kinase (MAPK) phoshorylation. In contrast to p44/42 MAPK, phosphatidylinositol 3-kinase activity was also induced in IL-13-unresponsive MIA PaCa-2, PANC-1, and T3M4 cells. All cells expressed and secreted IL-13. Neutralizing IL-13 antibodies inhibited the growth of ASPC-1 and CAPAN-1 cells. Immunohistochemical analysis of resected primary ductal adenocarcinoma specimens revealed high levels of IL-13 in 30 of 70 cases and its transmembrane receptor (IL-4R) in 28 of 70 cases, respectively. Fifteen of 16 specimens (94%) exhibiting high IL-13 and IL-4R coexpression had lymph node metastases, while only 30 of the remaining 54 samples (56%) had positive lymph nodes (p = 0.0134). CONCLUSION: IL-13 can act as an autocrine growth factor in PDAC. Endogenous expression of IL-13 in conjunction with IL-4R in the cancer cells seems to facilitate lymph node metastasis.

In vivo characterization of proliferation for discriminating cancer from pancreatic pseudotumors.

UNLABELLED: We have determined the ability of PET with the thymidine analog 3'-deoxy-3'-(18)F-fluorothymidine (FLT) to detect pancreatic cancer and to differentiate malignant from benign pancreatic lesions. METHODS: In this prospective study, (18)F-FLT PET was performed on 31 patients with undefined pancreatic lesions. Routine diagnostic procedures included endoscopic ultrasound, MRI, or multislice helical CT of the upper gastrointestinal tract in all patients. Uptake of (18)F-FLT was evaluated semiquantitatively by calculation of mean and maximal standardized uptake values (SUVs). Results were correlated to the reference methods, which were histopathology (23/31) or cytology/clinical follow-up (8/31). RESULTS: All 10 benign pancreatic lesions were negative on (18)F-FLT PET and showed only background activity (specificity, 100%; 90% confidence interval, 74%-100%). On visual interpretation, 15 of 21 malignant tumors presented as focal (18)F-FLT uptake higher than the surrounding background (sensitivity, 71.4%; 90% confidence interval, 52%-89%). (18)F-FLT PET missed 4 well-differentiated and 2 T1 cancers. Mean (18)F-FLT uptake was 3.1 in all malignant tumors (median, 2.8; range, 1.3-8.5), 3.7 in tumors with visual tracer uptake (median, 3.2; range, 2.1-8.5), and significantly higher in malignant than in benign tumors (mean/median, 1.4; range, 1.2-1.7; P<0.001). For discriminating cancer from benign pancreatic lesions, receiver-operating-characteristic analysis indicated a sensitivity of 81% and specificity of 100% (area under the curve, 0.93) using a mean (18)F-FLT SUV cutoff of 1.8 (maximal (18)F-FLT SUV: area under the curve, 0.92; SUV cutoff, 2.1). CONCLUSION: In this pilot study, focal uptake of the in vivo proliferation marker (18)F-FLT was detected exclusively in malignant tumors. (18)F-FLT PET may therefore be useful as a diagnostic adjunct for differentiating cancer from benign pancreatic lesions.

Metastasis to the pancreas: characterization by morphology and contrast enhancement features on CT and MRI.

AIMS: To investigate the characteristics of metastasis to the pancreas using computed tomography (CT) and magnetic resonance imaging (MRI). METHODS: Twenty-two patients with metastases to the pancreas were examined preoperatively by MRI (7/22) and/or multidetector CT (15/22). Pre- and post-contrast images were acquired and morphology, size, and contrast enhancement of the tumor analyzed. Subsequently, all patients underwent surgery, and the histopathologic findings were compared with the imaging results. RESULTS: In 22 patients, a total of 29 metastases were found on CT and MRI. These metastases originated from renal cell carcinomas (RCC; 22/29), colorectal carcinoma (3/29), and other malignancies (4/29). The metastases differed not in size or location, but in their contrast enhancement characteristics. RCC metastases had either intense homogeneous enhancement (in small lesions) or rim enhancement (in large lesions). Outer regions of colorectal metastases showed no difference from normal pancreatic tissue, whereas the inner area showed hypo-enhancement due to central necrosis. CONCLUSION: Imaging features of metastases from RCC point to their primary origin. While they can be distinguished from primary adenocarcinoma of the pancreas, differentiation from endocrine carcinoma might be difficult. Differentiation of colorectal carcinoma remains to be investigated on larger numbers of cases.

Aberrant gata-3 expression in human pancreatic cancer.

Gata-3 has been shown to specifically alter its expression patterns in different types of cancers. Recent evidence suggests that an interference of Gata-3 exists in the TGF-beta signaling pathway. To determine the role of Gata-3 in pancreatic cancer, pancreatic cancer samples were analyzed in comparison to normal pancreatic tissues. Furthermore, four different pancreatic cancer cell lines with different alterations of the TGF-beta pathway were studied. To evaluate if a potential relationship with TGF-beta signaling pathway exists, we correlated mRNA expression levels with the expression of TGF-betas, TGF-beta receptors, and Smad-3. Finally, we analyzed the influence of TGF-beta on Gata-3 expression in vitro. All pancreatic cancer samples demonstrated a marked overexpression of Gata-3 mRNA and protein. Immunohistochemical staining revealed strong and persistent cytoplasmic Gata-3 immunoreactivity in cancer cells. In an electrophoretic mobility shift assay, a disturbed nuclear translocation was confirmed. The expression of Gata-3 showed a significant correlation with the expression of TGF-betas, TGF-beta receptors, and Smad-3. TGF-beta responsive cell lines showed a downregulation of Gata-3 mRNA upon TGF-beta exposure, whereas in TGF-beta-unresponsive cell lines, Gata-3 mRNA expression persisted at high levels. Furthermore, strong specific upregulation of Gata-3 impaired nuclear translocation and its cooperative action with the TGF-beta pathway, suggesting that Gata-3 plays a central role in human pancreatic cancer.