The Peptidoglycan Recognition Protein 1 confers immune evasive properties on pancreatic cancer stem cells.

OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) has limited therapeutic options, particularly with immune checkpoint inhibitors. Highly chemoresistant 'stem-like' cells, known as cancer stem cells (CSCs), are implicated in PDAC aggressiveness. Thus, comprehending how this subset of cells evades the immune system is crucial for advancing novel therapies. DESIGN: We used the KPC mouse model (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre) and primary tumour cell lines to investigate putative CSC populations. Transcriptomic analyses were conducted to pinpoint new genes involved in immune evasion. Overexpressing and knockout cell lines were established with lentiviral vectors. Subsequent in vitro coculture assays, in vivo mouse and zebrafish tumorigenesis studies, and in silico database approaches were performed. RESULTS: Using the KPC mouse model, we functionally confirmed a population of cells marked by EpCAM, Sca-1 and CD133 as authentic CSCs and investigated their transcriptional profile. Immune evasion signatures/genes, notably the gene peptidoglycan recognition protein 1 (PGLYRP1), were significantly overexpressed in these CSCs. Modulating PGLYRP1 impacted CSC immune evasion, affecting their resistance to macrophage-mediated and T-cell-mediated killing and their tumourigenesis in immunocompetent mice. Mechanistically, tumour necrosis factor alpha (TNFα)-regulated PGLYRP1 expression interferes with the immune tumour microenvironment (TME) landscape, promoting myeloid cell-derived immunosuppression and activated T-cell death. Importantly, these findings were not only replicated in human models, but clinically, secreted PGLYRP1 levels were significantly elevated in patients with PDAC. CONCLUSIONS: This study establishes PGLYRP1 as a novel CSC-associated marker crucial for immune evasion, particularly against macrophage phagocytosis and T-cell killing, presenting it as a promising target for PDAC immunotherapy.

C-reactive protein postoperative values to predict clinically relevant postoperative pancreatic fistula after distal pancreatectomy.

INTRODUCTION: despite significant medical and technological advances, the incidence of postoperative pancreatic fistula (POPF) after distal pancreatectomy (DP) is reported to be between 3-45 %. The main objective of this study was to analyze the early post-surgical risk factors for developing POPF after DP. MATERIAL AND METHODS: a retrospective observational study was performed on a prospective basis of patients undergoing DP in a tertiary hospital from January 2011 to December 2021. Sociodemographic, preoperative analytical, tumor-related and postoperative complications variables were analyzed. RESULTS: of the 52 patients analyzed, 71.8 % of the sample had postoperative drains amylase elevation. However, 25.7 % of the total had grade-B and/or grade-C POPF. Univariate logistic regression with the variables studied showed the following as risk factors for B-C or clinically relevant POPF: amylase values in drainage at the 5th postoperative day (POD) (p = 0.097; 1.01 [1-1.01]), preoperative BMI (p = 0.015; 1.27 [1.04-1.55]) and C-reactive protein (CRP) value at the 3rd POD (p = 0.034; 1.01 [1.01-1.02]). The ROC curve of CRP value at the 3rd POD showed an area under the curve of 0.764 (95 % CI: 0.6-0.93) and the best cut-off point was 190 mg/l (sensitivity 89 % and specificity 67 %). CONCLUSIONS: CRP value at the 3rd POD is a predictive factor for POPF after DP. Early detection of patients at risk of POPF based on these characteristics could have an impact on their postoperative management.

Circulating tumor cells (Ctc) and kras mutant circulating free Dna (cfdna) detection in peripheral blood as biomarkers in patients diagnosed with exocrine pancreatic cancer.

BACKGROUND: Pancreatic cancer remains one of the most difficult cancers to treat with the poorest prognosis. The key to improving survival rates in this disease is early detection and monitoring of disseminated and residual disease. However, this is hindered due to lack reliable diagnostic and predictive markers which mean that the majority of patients succumb to their condition within a few months. METHODS: We present a pilot study of the detection circulating free DNA (cfDNA) combined with tumor specific mutation detection by digital PCR as a novel minimally invasive biomarker in pancreatic ductal adenocarcinoma (PDAC). This was compared to the detection of CTC by the CellSearch® system and a novel CTC enrichment strategy based on CD45 positive cell depletion. The aim of the study was to assess tumor specific DNA detection in plasma and CTC detection as prognostic markers in PDAC. RESULTS: We detected KRAS mutant cfDNA in 26% of patients of all stages and this correlated strongly with Overall Survival (OS), 60 days (95% CI: 19-317) for KRAS mutation positive vs 772 days for KRAS mutation negative (95% CI: 416-1127). Although, the presence of CTC detected by the CellSearch® system did correlate significantly with OS, 88 days (95% CI: 27-206) CTC positive vs 393 days CTC negative (95% CI: 284-501), CTC were detected in only 20% of patients, the majority of which had metastatic disease, whereas KRAS mutant cfDNA was detected in patients with both resectable and advanced disease. CONCLUSIONS: Tumor specific cfDNA detection and CTC detection are promising markers for the management of patients with PDAC, although there is a need to validate these results in a larger patient cohort and optimize the detection of CTC in PDAC by applying the appropriate markers for their detection.

Impact of Standard Versus Low Pneumoperitoneum Pressure on Peritoneal Environment in Laparoscopic Cholecystectomy. Randomized Clinical Trial.

BACKGROUND: High CO 2 pneumoperitoneum pressure during laparoscopy adversely affects the peritoneal environment. This study hypothesized that low pneumoperitoneum pressure may be linked to less peritoneal damage and possibly to better clinical outcomes. MATERIALS AND METHODS: One hundred patients undergoing scheduled laparoscopic cholecystectomy were randomized 1:1 to low or to standard pneumoperitoneum pressure. Peritoneal biopsies were performed at baseline time and 1 hour after peritoneum insufflation in all patients. The primary outcome was peritoneal remodeling biomarkers and apoptotic index. Secondary outcomes included biomarker differences at the studied times and some clinical variables such as length of hospital stay, and quality and safety issues related to the procedure. RESULTS: Peritoneal IL6 after 1 hour of surgery was significantly higher in the standard than in the low-pressure group (4.26±1.34 vs. 3.24±1.21; P =0.001). On the contrary, levels of connective tissue growth factor and plasminogen activator inhibitor-I were higher in the low-pressure group (0.89±0.61 vs. 0.61±0.84; P =0.025, and 0.74±0.89 vs. 0.24±1.15; P =0.028, respectively). Regarding apoptotic index, similar levels were found in both groups and were 44.0±10.9 and 42.5±17.8 in low and standard pressure groups, respectively. None of the secondary outcomes showed differences between the 2 groups. CONCLUSIONS: Peritoneal inflammation after laparoscopic cholecystectomy is higher when surgery is performed under standard pressure. Adhesion formation seems to be less in this group. The majority of patients undergoing surgery under low pressure were operated under optimal workspace conditions, regardless of the surgeon's expertise.

The best linear unbiased prediction (BLUP) method as a tool to estimate the lifetime risk of pancreatic ductal adenocarcinoma in high-risk individuals with no known pathogenic germline variants.

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related death in the Western world. The number of diagnosed cases and the mortality rate are almost equal as the majority of patients present with advanced disease at diagnosis. Between 4 and 10% of pancreatic cancer cases have an apparent hereditary background, known as hereditary pancreatic cancer (HPC) and familial pancreatic cancer (FPC), when the genetic basis is unknown. Surveillance of high-risk individuals (HRI) from these families by imaging aims to detect PDAC at an early stage to improve prognosis. However, the genetic basis is unknown in the majority of HRIs, with only around 10-13% of families carrying known pathogenic germline mutations. The aim of this study was to assess an individual's genetic cancer risk based on sex and personal and family history of cancer. The Best Linear Unbiased Prediction (BLUP) methodology was used to estimate an individual's predicted risk of developing cancer during their lifetime. The model uses different demographic factors in order to estimate heritability. A reliable estimation of heritability for pancreatic cancer of 0.27 on the liability scale, and 0.07 at the observed data scale as obtained, which is different from zero, indicating a polygenic inheritance pattern of PDAC. BLUP was able to correctly discriminate PDAC cases from healthy individuals and those with other cancer types. Thus, providing an additional tool to assess PDAC risk HRI with an assumed genetic predisposition in the absence of known pathogenic germline mutations.

The Spanish Familial Pancreatic Cancer Registry (PANGENFAM): a decade follow-up of individuals at high-risk for pancreatic cancer.

The Spanish Familial Pancreatic Cancer Registry (PANGENFAM) was established in 2009 and aims to characterize the genotype and phenotype of familial pancreatic cancer (FPC). Furthermore, an early detection screening program for pancreatic ductal adenocarcinoma (PDAC) is provided to healthy high-risk individuals from FPC and hereditary pancreatic cancer families (first-degree relatives). This article describes our experience over the last 10 years in high-risk screening. Hereditary and familial pancreatic cancer families were identified through the oncology and gastroenterology units. High-risk individuals underwent annual screening with endoscopic ultrasound (EUS) and magnetic resonance (MRI) from age 40 or 10 years younger than the youngest affected family member. Results: PANGENFAM has enrolled 290 individuals from 143 families, including 52 PDAC cases and 238 high-risk individuals. All high-risk individuals eligible for screening were offered to enter the surveillance program, with 143 currently participating. Pancreatic abnormalities were detected in 94 individuals (median age 53 years (29-83), with common findings including cystic lesions and inhomogeneous parenchyma. Imaging test concordance was 66%. Surgical intervention was performed in 4 high-risk individuals following highly suspicious lesions detected by imaging. PANGENFAM is a valuable resource for science innovation, such as biobanking, with clinical and imaging data available for analysis. For high-risk families, it may offer a potential for early diagnosis. Collaboration with other national and international registries is needed to increase our understanding of the disease biology and to standardize criteria for inclusion and follow-up, optimizing cost-effectiveness and efficacy.

Repeated pancreatic resection for pancreatic metastases from renal cell Carcinoma: A Spanish multicenter study (PANMEKID).

BACKGROUND AND OBJECTIVES: Recurrent isolated pancreatic metastasis from Renal Cell Carcinoma (RCC) after pancreatic resection is rare. The purpose of our study is to describe a series of cases of relapse of pancreatic metastasis from renal cancer in the pancreatic remnant and its surgical treatment with a repeated pancreatic resection, and to analyse the results of both overall and disease-free survival. METHODS: Multicenter retrospective study of patients undergoing pancreatic resection for RCC pancreatic metastases, from January 2010 to May 2020. Patients were grouped into two groups depending on whether they received a single pancreatic resection (SPS) or iterative pancreatic resection. Data on short and long-term outcome after pancreatic resection were collected. RESULTS: The study included 131 pancreatic resections performed in 116 patients. Thus, iterative pancreatic surgery (IPS) was performed in 15 patients. The mean length of time between the first pancreatic surgery and the second was 48.9 months (95 % CI: 22.2-56.9). There were no differences in the rate of postoperative complications. The DFS rates at 1, 3 and 5 years were 86 %, 78 % and 78 % vs 75 %, 50 % and 37 % in the IPS and SPS group respectively (p = 0.179). OS rates at 1, 3, 5 and 7 years were 100 %, 100 %, 100 % and 75 % in the IPS group vs 95 %, 85 %, 80 % and 68 % in the SPS group (p = 0.895). CONCLUSION: Repeated pancreatic resection in case of relapse of pancreatic metastasis of RCC in the pancreatic remnant is justified, since it achieves OS results similar to those obtained after the first resection.

Establishment of Pancreatic Cancer-Derived Tumor Organoids and Fibroblasts From Fresh Tissue.

Tumor organoids are three-dimensional (3D) ex vivo tumor models that recapitulate the biological key features of the original primary tumor tissues. Patient-derived tumor organoids have been used in translational cancer research and can be applied to assess treatment sensitivity and resistance, cell-cell interactions, and tumor cell interactions with the tumor microenvironment. Tumor organoids are complex culture systems that require advanced cell culture techniques and culture media with specific growth factor cocktails and a biological basement membrane that mimics the extracellular environment. The ability to establish primary tumor cultures highly depends on the tissue of origin, the cellularity, and the clinical features of the tumor, such as the tumor grade. Furthermore, tissue sample collection, material quality and quantity, as well as correct biobanking and storage are crucial elements of this procedure. The technical capabilities of the laboratory are also crucial factors to consider. Here, we report a validated SOP/protocol that is technically and economically feasible for the culture of ex vivo tumor organoids from fresh tissue samples of pancreatic adenocarcinoma origin, either from fresh primary resected patient donor tissue or patient-derived xenografts (PDX). The technique described herein can be performed in laboratories with basic tissue culture and mouse facilities and is tailored for wide application in the translational oncology field.

Pancreatic metastases from renal cell carcinoma. Postoperative outcome after surgical treatment in a Spanish multicenter study (PANMEKID).

BACKGROUND: Renal Cell Carcinoma (RCC) occasionally spreads to the pancreas. The purpose of our study is to evaluate the short and long-term results of a multicenter series in order to determine the effect of surgical treatment on the prognosis of these patients. METHODS: Multicenter retrospective study of patients undergoing surgery for RCC pancreatic metastases, from January 2010 to May 2020. Variables related to the primary tumor, demographics, clinical characteristics of metastasis, location in the pancreas, type of pancreatic resection performed and data on short and long-term evolution after pancreatic resection were collected. RESULTS: The study included 116 patients. The mean time between nephrectomy and pancreatic metastases' resection was 87.35 months (ICR: 1.51-332.55). Distal pancreatectomy was the most performed technique employed (50 %). Postoperative morbidity was observed in 60.9 % of cases (Clavien-Dindo greater than IIIa in 14 %). The median follow-up time was 43 months (13-78). Overall survival (OS) rates at 1, 3, and 5 years were 96 %, 88 %, and 83 %, respectively. The disease-free survival (DFS) rate at 1, 3, and 5 years was 73 %, 49 %, and 35 %, respectively. Significant prognostic factors of relapse were a disease free interval of less than 10 years (2.05 [1.13-3.72], p 0.02) and a history of previous extrapancreatic metastasis (2.44 [1.22-4.86], p 0.01). CONCLUSIONS: Pancreatic resection if metastatic RCC is found in the pancreas is warranted to achieve higher overall survival and disease-free survival, even if extrapancreatic metastases were previously removed. The existence of intrapancreatic multifocal compromise does not always warrant the performance of a total pancreatectomy in order to improve survival.

Anterograde intraoperative pancreatic stent placement and round ligament patch to prevent pancreatic fistula after distal pancreatectomy. / Colocación intraoperatoria anterógrada de stent pancreático y plastia de ligamento redondo para prevenir la fístula pancreática tras la pancreatectomía distal.

Postoperative pancreatic fistula in distal pancreatectomy is one of the most important complications in this surgery and it is associated with high morbidity and mortality. Pancreatic fistula after distal pancreatectomy remains an unsolved problem and none preventive procedure has been shown effectively. We present a new technique that combine pancreatic stent placement with round ligament autologous patch over pancreatic edge. A guide is introduced through Wirsung duct prior to stent placement. After stent assessment, Wirsung duct is closed. Finally, falciform ligament autologous patch is placed over pancreatic edge. After 6-8 weeks, the stent is removed by oral endoscopy. This technique introduces a new issue on the pancreatic fistula prevention.

Preoperative clinical model to predict myocardial injury after non-cardiac surgery: a retrospective analysis from the MANAGE cohort in a Spanish hospital.

OBJECTIVES: To determine preoperative factors associated to myocardial injury after non-cardiac surgery (MINS) and to develop a prediction model of MINS. DESIGN: Retrospective analysis. SETTING: Tertiary hospital in Spain. PARTICIPANTS: Patients aged ≥45 years undergoing major non-cardiac surgery and with at least two measures of troponin levels within the first 3 days of the postoperative period. All patients were screened for the MANAGE trial. PRIMARY AND SECONDARY OUTCOME MEASURES: We used multivariable logistic regression analysis to study risk factors associated with MINS and created a score predicting the preoperative risk for MINS and a nomogram to facilitate bed-side use. We used Least Absolute Shrinkage and Selection Operator method to choose the factors included in the predictive model with MINS as dependent variable. The predictive ability of the model was evaluated. Discrimination was assessed with the area under the receiver operating characteristic curve (AUC) and calibration was visually assessed using calibration plots representing deciles of predicted probability of MINS against the observed rate in each risk group and the calibration-in-the-large (CITL) and the calibration slope. We created a nomogram to facilitate obtaining risk estimates for patients at pre-anaesthesia evaluation. RESULTS: Our cohort included 3633 patients recruited from 9 September 2014 to 17 July 2017. The incidence of MINS was 9%. Preoperative risk factors that increased the risk of MINS were age, American Status Anaesthesiology classification and vascular surgery. The predictive model showed good performance in terms of discrimination (AUC=0.720; 95% CI: 0.69 to 0.75) and calibration slope=1.043 (95% CI: 0.90 to 1.18) and CITL=0.00 (95% CI: -0.12 to 0.12). CONCLUSIONS: Our predictive model based on routinely preoperative information is highly affordable and might be a useful tool to identify moderate-high risk patients before surgery. However, external validation is needed before implementation.

Gastrointestinal stromal tumors: actin expression, a new prognostic factor?

The aim of this study is to analyze the clinical outcome of gastrointestinal stromal tumors (GISTs) and to determine new prognostic factors. We perform a retrospective study of all the patients diagnosed with GIST in any location and operated on between 2000 and 2008 at our institution. We analyzed 35 patients, 16 males (45.7%) and 19 females (54.3%), with a mean age of 64 +/- 13.8 years. The tumors were located in the stomach in 22 patients (62.9%), in the small bowel in 10 (28.6%), and the retroperitoneum in three (8.6%). Referring to gastric GIST, endoscopy revealed an ulceration in the mucosa in five cases, suggesting an epithelial neoplasm. In all these cases, pathology of the biopsy specimen was nonconclusive. Survival rate at 1 and 5 years was 94.3 and 88.6 per cent, respectively. Disease-free survival at 1 and 2 years was 91.4 and 88.6 per cent, respectively. Analyzing prognostic factors, a lower disease-free survival was observed among patients with constitutional syndrome at diagnosis (P = 0.000), small bowel GIST (P = 0.037), and tumors not expressing actin (P = 0.015). A lower global survival was observed among men (P = 0,036), patients with an abdominal mass (P = 0.033) or with constitutional syndrome (P = 0.007) at diagnosis and tumors at a retroperitoneal location (P = 0.0002). Gastric GIST may be confused with epithelial neoplasms, modifying the surgery. In our patients, masculine gender, constitutional syndrome and abdominal mass at diagnosis, small bowel and retroperitoneal location, and actin negative tumors are bad prognostic factors.

Clinical outcome at ten years after laparoscopic fundoplication: Nissen versus Toupet.

Laparoscopic surgery has become the elective approach for the surgical treatment of gastroesophageal reflux disease in the last decade. Outcome data beyond 10 years are available for open fundoplication, with good-to-excellent results, but few studies report long-term follow-up after laparoscopic fundoplication. We performed a retrospective study of all the patients that underwent laparoscopic Nissen and Toupet fundoplications as antireflux surgery between 1995 and 1998 in our institution. To evaluate the long-term results, a face-to-face interview was performed in 2009. One hundred and six patients were included in the study. Surgical techniques performed were Nissen fundoplication (NF) in 56 patients and Toupet (TF) in 50. Complication rate was 4 per cent in both groups (nonsignificant [NS]). Two patients (4%) of NF required reoperation because of dysphagia. After 10 years, 10 per cent of the patients remain symptomatic in both groups. Fifteen per cent of NF take daily inhibitors of the proton pump versus 14 per cent of TF (NS). Twenty per cent of NF refer dysphagia, all of them without evidence of stenosis at endoscopy or contrasted studies. The satisfaction rate of the patients was 96 per cent in NF and 98 per cent in TF. Laparoscopic Toupet fundoplication seems to be as safe and long-term effective as Nissen, but with a lower incidence of postoperative dysphagia. In our experience Toupet fundoplication should be the elective approach for the surgical treatment of gastroesophageal reflux disease.

Relevance of positive resection margins in ductal pancreatic adenocarcinoma and prognostic factors. / Relevancia del margen de resección positivo en adenocarcinoma ductal de páncreas y otros factores pronósticos.

INTRODUCTION: Currently, R1 resection is defined by the presence of tumor cells within <1mm of the resection margin. The main aim of this study was to analyze the impact of positive margins (R1) on survival outcomes in pancreatic cancer. METHODS: We performed a retrospective analysis with multivariate regression analysis of a prospective database from 2008-2017, which included resection margin status, expanded resection margin (R1<1mm), vascular resection, lymphatic involvement, surgical complications, tumor differentiation grade and adjuvant treatment. RESULTS: A total of 80 patients were analyzed: 42 (52%) R1; 38 (48%) R0. No differences were found in the composition of the two groups except for the vascular resection, which was more frequent in the R1 group: 12 (21%) vs 2 (3%). Overall survival in the R0 group was 19 months vs 24 months in the R1 group (p=0.13). Wide R1 (R1<1mm) had an overall survival of 21 months versus 31 months in wide R0 (p=0.55). In the multivariate analysis, only lymph node involvement (p=0.02, HR=2.88), tumor differentiation (p=0.02, HR=3.2) and adjuvant therapy (p<0.01; HR=0.21) were found to be factors related to survival. CONCLUSIONS: R1 resection is not an independent risk factor. Lymph node involvement, differentiation grade and adjuvant treatment are prognostic factors. The benefit of expanding the resection margins should be demonstrated. More studies are needed to assess the impact of the resection margin.

Lumen-apposing metal stents versus biliary fully-covered metal stents for EUS-guided drainage of pancreatic fluid collections: a case control study: Meeting presentations: European Society of Gastrointestinal Endoscopy ESGE Days 2018.

Background and study aims Endoscopic ultrasound (EUS)-guided drainage has become first-line treatment for pancreatic fluid collections (PFC). The aim of this study was to compare the effectiveness and safety of biliary fully-covered self-expandable metal stents (BFCSEMS) and lumen-apposing metal stents with electrocautery (EC-LAMS). Patients and methods From April 2008 to March 2017, consecutive patients with symptomatic PFC drained under EUS-guidance with metal stents were included. Patients drained with EC-LAMS were considered the study group and those drained with BFCSEMS the control group. Two primary endpoints were evaluated: effectiveness (defined as reduction of ≥ 50 % of PFC size in cross-sectional imaging and improvement of symptoms 6 months after the transmural drainage) and safety. Results Thirty patients were drained with EC-LAMS and 60 patients with BFCSEMS. Patients and PFC baseline characteristics in both groups were similar. Use of a coaxial double pigtail plastic stent and a nasocystic lavage catheter was significantly less frequent in patients drained with EC-LAMS (33 % vs. 100 %, and 13 % vs. 58 %, respectively; P  < 0.0001). Technical success was 100 % in both groups. Procedure time was < 30 minutes in all patients drained with EC-LAMS and over 30 minutes in all patients drained with BFCSEMS ( P  = 0.0001). Clinical success was higher with a tendency to significance in patients drained with EC-LAMS (96 % vs. 82 %, P  = 0.055) and the adverse event rate was lower (4 % vs. 18 %, P  = 0.04). No case of procedure-related mortality was recorded. Conclusions EC-LAMS and BFCSEMS are both effective for EUS-guided drainage of PFC. However, EC-LAMS requires less time to be performed and appears to be safer.

Volvulus of the small bowel in adults.

The volvulus of the small bowel is a surgical emergency, causing small bowel obstruction. We performed a retrospective study of all the patients diagnosed and treated with small bowel volvulus between 1977 and 2007 at our institution. One hundred twenty-nine patients were analyzed. Thirty-nine patients presented primary volvulus and 90 secondary ones. The most frequent symptom was sudden abdominal pain. CT scan was the best diagnostic method with an accuracy of 83 per cent. Necrotic small bowel loops appeared in 46.5 per cent of the patients. Eighteen patients had postoperative complications (14%). Mortality rate was 9.3 per cent. A higher mortality is observed among patients with previous abdominal surgeries and cardiopathies. Necrotic loops are associated with higher mortality and incidence of surgical complications; patients with diabetes are associated with a higher incidence of necrotic loops. Cardiopathies are associated with more frequent medical and surgical complications. Recurrence rate was 3.9 per cent associated with simple devolvulation. Primary volvulus are more frequent among males and patients with diabetes. Jejunal location is associated with primary volvulus and these correlate with a higher incidence of necrotic loops. Primary volvulus presents a higher incidence of surgical complications. A bowel obstruction with sudden abdominal pain must be suspicious of small bowel volvulus. The main aim is to achieve an early diagnosis to prevent a necrotic small bowel. CT scan is the imaging test with the best diagnostic accuracy. Primary volvulus, the presence of necrotic loops, and patients with cardiopathies, diabetes mellitus, and with previous abdominal surgery are associated with a worse outcome.

Fourth-portion duodenal diverticulum causing massive upper gastrointestinal bleeding.

Most duodenal diverticula are asymptomatic, incidentally discovered at endoscopy or barium studies. Upper gastrointestinal bleeding has been described, but it is an infrequent complication. We describe the 14th case reported in the literature of massive upper gastrointestinal bleeding originating from a duodenal diverticulum.