Serum Metabolite Biomarkers for Pancreatic Tumors: Neuroendocrine and Pancreatic Ductal Adenocarcinomas-A Preliminary Study.

BACKGROUND: Pancreatic cancer is the most common pancreatic solid malignancy with an aggressive clinical course and low survival rate. There are a limited number of reliable prognostic biomarkers and a need to understand the pathogenesis of pancreatic tumors; neuroendocrine (PNET) and pancreatic ductal adenocarcinomas (PDAC) encouraged us to analyze the serum metabolome of pancreatic tumors and disturbances in the metabolism of PDAC and PNET. METHODS: Using the AbsoluteIDQ® p180 kit (Biocrates Life Sciences AG, Innsbruck, Austria) with liquid chromatography-mass spectrometry (LC-MS), we identified changes in metabolite profiles and disrupted metabolic pathways serum of NET and PDAC patients. RESULTS: The concentration of six metabolites showed statistically significant differences between the control group and PDAC patients (p.adj < 0.05). Glutamine (Gln), acetylcarnitine (C2), and citrulline (Cit) presented a lower concentration in the serum of PDAC patients, while phosphatidylcholine aa C32:0 (PC aa C32:0), sphingomyelin C26:1 (SM C26:1), and glutamic acid (Glu) achieved higher concentrations compared to serum samples from healthy individuals. Five of the tested metabolites: C2 (FC = 8.67), and serotonin (FC = 2.68) reached higher concentration values in the PNET serum samples compared to PDAC, while phosphatidylcholine aa C34:1 (PC aa C34:1) (FC = -1.46 (0.68)) had a higher concentration in the PDAC samples. The area under the curves (AUC) of the receiver operating characteristic (ROC) curves presented diagnostic power to discriminate pancreatic tumor patients, which were highest for acylcarnitines: C2 with AUC = 0.93, serotonin with AUC = 0.85, and PC aa C34:1 with AUC = 0.86. CONCLUSIONS: The observations presented provide better insight into the metabolism of pancreatic tumors, and improve the diagnosis and classification of tumors. Serum-circulating metabolites can be easily monitored without invasive procedures and show the present clinical patients' condition, helping with pharmacological treatment or dietary strategies.

Update of the diagnostic and therapeutic guidelines for gastro-entero-pancreatic neuroendocrine neoplasms (recommended by the Polish Network of Neuroendocrine Tumours) [Aktualizacja zalecen ogólnych dotyczacych postepowania diagnostyczno-terapeutycznego w nowotworach neuroendokrynnych ukladu pokarmowego (rekomendowane przez Polska Siec Guzów Neuroendokrynnych)].

Continuous progress in the diagnostics and treatment of neuroendocrine neoplasms (NENs), the emerging results of new clinical trials, and the new guidelines issued by medical societies have prompted experts from the Polish Network of Neuroendocrine Tumours to update the 2017 recommendations regarding the management of neuroendocrine neoplasms. This article presents the general recommendations for the management of NENs, resulting from the findings of the experts participating in the Fourth Round Table Conference, entitled "Polish Guidelines for the Diagnostics and Treatment of Neuroendocrine Neoplasms of the gastrointestinal tract, Zelechów, June 2021". Drawing from the extensive experience of centres treating these cancers, we hope that we have managed to formulate the optimal method of treating patients with NENs, applying the latest reports and achievements in the field of medicine, which can be effectively implemented in our country. The respective parts of this work present the approach to the management of: NENs of the stomach and duodenum (including gastrinoma), pancreas, small intestine, and appendix, as well as large intestine.

Pancreatic neuroendocrine neoplasms - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne trzustki - uaktualnione zasady diagnostyki i leczenia (rekomendowane przez Polska Siec Guzów Neuroendokrynych)].

In this paper, we present the current guidelines for the diagnostics and management of pancreatic neuroendocrine neoplasms (PanNENs) developed by Polish experts providing care for these patients in everyday clinical practice. In oncological diagnostics, in addition to biochemical tests, molecular identification with the use of NETest liquid biopsy and circulating microRNAs is gaining importance. Both anatomical and functional examinations (including new radiopharmaceuticals) are used in imaging diagnostics. Histopathological diagnosis along with immunohistochemical examination still constitute the basis for therapeutic decisions. Whenever possible, surgical procedure is the treatment of choice. Pharmacological management including biotherapy, radioisotope therapy, targeted molecular therapy and chemotherapy are important methods of systemic therapy. Treatment of PanNENs requires a multidisciplinary team of specialists in the field of neuroendocrine neoplasms.

Gastroduodenal neuroendocrine neoplasms including gastrinoma - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne zoladka i dwunastnicy z uwzglednieniem gastrinoma - uaktualnione zasady postepowania (rekomendowane przez Polska Siec Guzów Neuroendokrynnych)].

After another meeting of experts of the Polish Network of Neuroendocrine Tumours, updated recommendations for the management of patients with gastric and duodenal neuroendocrine neoplasms, including gastrinoma, have been issued. As before, the epidemiology, pathogenesis and clinical symptoms of these neoplasms have been discussed, as well as the principles of diagnostic procedures, including biochemical and histopathological diagnostics and tumour localisation, highlighting the changes introduced in the recommendations. Updated principles of therapeutic management have also been presented, including endoscopic and surgical treatment, and the options of pharmacological and radioisotope treatment. The importance of monitoring patients with gastric and duodenal NENs, including gastrinoma, has also been emphasised.

Colorectal neuroendocrine neoplasms - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne jelita grubego - uaktualnione zasady diagnostyki i leczenia (rekomendowane przez Polska Siec Guzów Neuroendokrynych)].

Colorectal neuroendocrine neoplasm (CRNEN), especially rectal tumours, are diagnosed with increased frequency due to the widespread use of colonoscopy, including screening examinations. It is important to constantly update and promote the principles of optimal diagnostics and treatment of these neoplasms. Based on the latest literature and arrangements made at the working meeting of the Polish Network of Neuroendocrine Tumours (June 2021), this paper includes updated and supplemented data and guidelines for the management of CRNEN originally published in Endokrynologia Polska 2017; 68: 250-260.

Neuroendocrine neoplasms of the small intestine and the appendix - update of the diagnostic and therapeutic guidelines (recommended by the Polish Network of Neuroendocrine Tumours) [Nowotwory neuroendokrynne jelita cienkiego i wyrostka robaczkowego - uaktualnione zasady diagnostyki i leczenia (rekomendowane przez Polska Siec Guzów Neuroendokrynnych)].

Updated Polish recommendations for the management of patients with neuroendocrine neoplasms (NENs) of the small intestine (SINENs) and of the appendix (ANENs) are presented here. The small intestine, and especially the ileum, is one of the most common locations for these neoplasms. Most of them are well-differentiated and slow-growing tumours; uncommonly - neuroendocrine carcinomas. Their symptoms may be untypical and their diagnosis may be delayed or accidental. Najczesciej pierwsza manifestacja ANEN jest jego ostre zapalenie. Typical symptoms of carcinoid syndrome occur in approximately 20-30% of SINENs patients with distant metastases. In laboratory diagnostics the assessment of 5-hydroxyindoleacetic acid concentration is helpful in the diagnosis of carcinoid syndrome. The most commonly used imaging methods are ultrasound examination, computed tomography, magnetic resonance imaging, colonoscopy and somatostatin receptor imaging. Histopathological examination is crucial for the proper diagnosis and treatment of patients with SINENs and ANENs. The treatment of choice is a surgical procedure, either radical or palliative. Long-acting somatostatin analogues (SSAs) are essential in the medical treatment of functional and non-functional SINENs. In patients with SINENs, at the stage dissemination with progression during SSAs treatment, with high expression of somatostatin receptors, radioisotope therapy should be considered first followed by targeted therapies - everolimus. After the exhaustion of the above available therapies, chemotherapy may be considered in selected cases. Recommendations for patient monitoring are also presented.

Skin Metastases of Gastrointestinal Neuroendocrine Tumors - Literature Review.

<b> Introduction:</b> Gastrointestinal neuroendocrine neoplasms arise from cells of the diffuse endocrine system (DES) located in the digestive tract. They are often diagnosed in an advanced stage, when distant metastases appear. Skin metastases of neuroendocrine tumors are extremely rare. </br></br> <b>Aim:</b> The aim of the study was to collect and analyze cases of skin metastases of gastrointestinal neuroendocrine neoplasms. </br></br> <b>Materials and methods:</b> A literature search across PubMed and Medline databases from 1969 up to 2021 was performed. We reviewed English literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. The following keywords were used: "neuroendocrine tumor", "neuroendocrine neoplasm", "neuroendocrine carcinoma", "NET", "NEN", "skin and cutaneous metastases", "lymph nodes". The characteristics of patients, grading, tumor localization and other data that was found in publications were assessed. Case reports and case series were included. </br></br> <b>Results:</b> The initial search strategy yielded 14 results in PubMed and 3 in the Medline database. We removed duplicates after we imported the citations with a citation manager. We found 17 publications concerning skin metastases of neuroendocrine neoplasms. The analysis of 18 cases concerned 13 NECs and 5 NETs. In most cases, the metastases are small, painless and located on the scalp or lower extremities. Skin metastases may be the first symptom of the disease. The pancreas is the most common primary tumor site.</br></br> <b>Conclusions:</b> NEN metastases to the skin are often diagnosed with disseminated neoplastic process, which is associated with poor prognosis and high mortality. NET metastases to the skin may occur with an unknown primary site. Skin metastases of neuroendocrine tumors should be considered during the diagnosis of skin tumors.

Evaluation of Risk Factors for Distant and Lymph Node Metastasis of Pancreatic Neuroendocrine Tumors.

Purpose: Metastases of pancreatic neuroendocrine tumors (pNETs) can be found at the time of diagnosis in 20-50% of cases. Small asymptomatic tumors may be left for observation; however, they can metastasize. The aim of the study was to evaluate risk factors for distant and lymph node metastases of pNETs. Patients and methods: One hundred and fourteen patients with postoperatively confirmed pNET were analyzed retrospectively in a single ENETS Center of Excellence. The relationship between location, size, differentiation of the tumor, and occurrence of lymph node and distant metastases was analyzed. Results: pNETs' location was pancreatic head - 38 (33.3%), body or tail - 68 (59.7%), and 8 (7.0%) involved the entire organ. Fifty-six (49.1%) tumors were graded G1, 50 (43.9%) G2, and 8 (7.0%) G3. Seventy-two (63.2%) tumors were ≥2 cm in diameter, and 42 (36.8%) <2 cm. Twenty-two (19.3%) patients had distant metastases and 47 (41.2%) had lymph node metastases. In ≥2 cm tumors distant and lymph node metastases were more frequent (p < 0.05). Distant metastases incidence was significantly higher in distally located tumors (p = 0.01) and in G2 and G3 tumors (p < 0.01). In 9.5% of <2cm tumors, distant metastases were present at diagnosis. Conclusion: Distant metastases are more often found in larger, distally located pNETs grade G2 and G3, while a higher occurrence of lymph node metastases seems to be associated only with larger tumor size. A considerable number of tumors <2 cm in size have distant metastases already at the diagnosis, which might indicate the need for careful qualification of smaller lesions for observation.

Which Suture to Choose in Hepato-Pancreatic-Biliary Surgery? Assessment of the Influence of Pancreatic Juice and Bile on the Resistance of Suturing Materials-In Vitro Research.

(1) Background: The choice of appropriate surgical suture during operation is of great significance. Currently, there are no objective studies regarding the resistance of commonly used sutures in biliary tract surgery. (2) Methods: This fact leads one to conduct research concerning the resistance of the sutures (Polydioxanone, Poliglecaprone, Poliglactin 910, and their analogues coated with antibacterial triclosan) in the environment of sterile and contaminated bile and pancreatic juice. Tensile strength was tested at days 0, 7, 14, 21, and 28 of research. The study was performed in in vitro conditions for 28 days. (3) Results: Pancreatic juice and bile has a significant influence on the tensile strength of each suture. (4) Conclusions: The study indicated that sutures made of polydioxanone had the best qualities during the entire experiment.

A Single-Center Retrospective Study of Selected Clinical Parameters and Intraoperative Fluid Management of Patients Undergoing Pancreatoduodenectomy.

BACKGROUND Pancreatoduodenectomy is an extensive procedure with a very high risk of complications. Appropriate intraoperative fluid therapy is a subject of ongoing debate. The aim of this retrospective study was to analyze the relationship between selected preoperative parameters, intraoperative fluid therapy, and catecholamines administration during pancreatoduodenectomy. MATERIAL AND METHODS From 2011 through 2017, among pancreatoduodenectomies performed at a single university hospital, 192 patients met the inclusion criteria of the study: 105 (54.7%) males and 87 (45.3%) females with a mean age of 60.06 (±11.63) years. Correlations were assessed between sex, age, body mass index (BMI), selected comorbidities, surgery duration, American Society of Anesthesiologists (ASA) Physical Status (PS) scale, preoperative endoscopic retrograde cholangiopancreatography (ERCP) and intraoperative catecholamine administration, intraoperative fluid supply, red blood cell (RBC) concentrate and fresh frozen plasma (FFP) supply, blood loss, and diuresis. RESULTS A need for catecholamines has been shown to be more frequent in smokers (P=0.01), patients with cardiovascular comorbidities (P=0.037), high ASA PS scores (P=0.003), and preoperative ERCP (P=0.011). The need for intraoperative transfusion of RBC concentrate was more frequent in smokers (P=0.005). Surgical time was significantly longer in males (P=0.014). Among females, liberal intraoperative fluid therapy (>7.9 ml/kg/h) was more frequent in patients with thyroid comorbidities (P=0.003). CONCLUSIONS The findings of this retrospective study demonstrate the influence of comorbidities, ASA PS class, and catecholamine use on fluid therapy during pancreatoduodenectomy.

Utility of fistula risk score in assessing the risk of postoperative pancreatic fistula occurrence and other significant complications after different types of pancreatic neuroendocrine tumor resections.

Purpose: This study was performed to evaluate the utility of the fistula risk score (FRS) and its components in predicting the occurrence of postoperative pancreatic fistula and other significant postoperative complications after resections of pancreatic neuroendocrine tumors. Methods: Retrospective analysis of 131 patients operated on for pancreatic neuroendocrine tumors between 2015 and 2021 was performed. The correlation of the FRS scale with the occurrence of postoperative pancreatic fistulas and postoperative complications according to the Clavien-Dindo classification was analyzed; only in 109 cases of distal resections and pancreatoduodenectomies (PD). Results: Soft pancreatic texture and intraoperative blood loss of >700 mL are risk factors for clinically significant pancreatic fistula (P = 0.001 and P = 0.001, respectively) and significant postoperative complications (P = 0.016 and P = 0.001, respectively). Wirsung duct diameter (WDD) was associated only with the occurrence of postoperative pancreatic fistula (P = 0.013). FRS scale is associated with the occurrence of pancreatic fistulas and clinically significant postoperative complications in cases of distal resections and PDs (P < 0.001 and P = 0.005, respectively). Postoperative complications are correlated with the occurrence of fistula type B or C (P < 0.001). Conclusion: Soft pancreatic texture, intraoperative blood loss of >700 mL, and a WDD of ≤3 mm are risk factors for clinically significant postoperative pancreatic fistula. FRS may be applied not only in PDs but also in distal pancreatectomies. Unfortunately, it is not used in total pancreatic resections and enucleations since FRS takes into account the WDD.

Pancreatic neuroendocrine carcinoma metastasis to the skin.

Not required for Clinical Vignette.

Small Intestinal Intussusception Due to Complicated Giant Jejunal Diverticulosis.

Background: Jejunal diverticulosis and jejunal lipomatosis are uncommon conditions. Usually asymptomatic, they may cause severe complications in some cases. Intussusception is unusual in adults, but when diagnosed swiftly it can be treated surgically, usually with good outcome. Case presentation: We present a 60-year-old female patient with a history of chronic malnutrition and anemia, complaining of acute abdominal pain, vomiting and diarrhea. Contrast-enhanced abdominal computed tomography (CT) showed intussusception, multiple giant jejunal diverticula and multiple lipomas. The patient underwent urgent surgery, but radical treatment was not possible due to the extent of the diseases. One month later, another surgery was needed due to ileostomy obstruction caused by lipomas. The patient's condition deteriorated due to malnutrition and concomitant metabolic disorders, which eventually led to her demise. Conclusions: Radical treatment is not always possible in an extensive jejunal disease. Prolonged malnutrition impairs postoperative healing, and therefore surgical or nutritional treatment should be considered in jejunal diverticulosis before the onset of severe complications requiring urgent surgical intervention.

Prospective Evaluation of the NETest as a Liquid Biopsy for Gastroenteropancreatic and Bronchopulmonary Neuroendocrine Tumors: An ENETS Center of Excellence Experience.

BACKGROUND: There is a substantial unmet clinical need for an accurate and effective blood biomarker for neuroendocrine neoplasms (NEN). We therefore evaluated, under real-world conditions in an ENETS Center of Excellence (CoE), the clinical utility of the NETest as a liquid biopsy and compared its utility with chromogranin A (CgA) measurement. METHODS: The cohorts were: gastroenteropancreatic NEN (GEP-NEN; n = 253), bronchopulmonary NEN (BPNEN; n = 64), thymic NEN (n = 1), colon cancer (n = 37), non-small-cell lung cancer (NSCLC; n = 63), benign lung disease (n = 59), and controls (n = 86). In the GEPNEN group, 164 (65%) had image-positive disease (IPD, n = 135) or were image-negative but resection-margin/biopsy-positive (n = 29), and were graded as G1 (n = 106), G2 (n = 49), G3 (n = 7), or no data (n = 2). The remainder (n = 71) had no evidence of disease (NED). In the BPNEN group, 43/64 (67%) had IPD. Histology revealed typical carcinoids (TC, n = 14), atypical carcinoids (AC, n = 14), small-cell lung cancer (SCLC, n = 11), and large-cell neuroendocrine carcinoma (LCNEC, n = 4). Disease status (stable or progressive) was evaluated according to RECIST v1.1. Blood sampling involved NETest (n = 563) and NETest/CgA analysis matched samples (n = 178). NETest was performed by PCR (on a scale of 0-100), with a score ≥20 reflecting a disease-positive status and >40 reflecting progressive disease. CgA positivity was determined by ELISA. Samples were deidentified and measurements blinded. The Kruskal-Wallis, Mann-Whitney U, and McNemar tests, and the area under the curve (AUC) of the receiver-operating characteristics (ROC) were used in the statistical analysis. RESULTS: In the GEPNEN group, NETest was significantly higher (34.4 ± 1.8, p < 0.0001) in disease-positive patients than in patients with NED (10.5 ± 1, p < 0.0001), colon cancer patients (18 ± 4, p < 0.0004), and controls (7 ± 0.5, p < 0.0001). Sensitivity for detecting disease compared to controls was 89% and specificity was 94%. NETest levels were increased in G2 vs. G1 (39 ± 3 vs. 32 ± 2, p = 0.02) and correlated with stage (localized: 26 ± 2 vs. regional/distant: 40 ± 3, p = 0.0002) and progression (55 ± 5 vs. 34 ± 2 in stable disease, p = 0.0005). In the BPNEN group, diagnostic sensitivity was 100% and levels were significantly higher in patients with bronchopulmonary carcinoids (BPC; 30 ± 1.3) who had IPD than in controls (7 ± 0.5, p < 0.0001), patients with NED (24.1 ± 1.3, p < 0.005), and NSCLC patients (17 ± 3, p = 0.0001). NETest levels were higher in patients with poorly differentiated BPNEN (LCNEC + SCLC; 59 ± 7) than in those with BPC (30 ± 1.3, p = 0.0005) or progressive disease (57.8 ± 7), compared to those with stable disease (29.4 ± 1, p < 0.0001). The AUC for differentiating disease from controls was 0.87 in the GEPNEN group and 0.99 in BPC patients (p < 0.0001). Matched CgA analysis was performed in 178 patients. In the GEPNEN group (n = 135), NETest was significantly more accurate for detecting disease (99%) than CgA positivity (53%; McNemar test χ2 = 87, p < 0.0001). In the BPNEN group (n = 43), NETest was significantly more accurate for disease detection (100%) than CgA positivity (26%; McNemar's test χ2 = 30, p < 0.0001). CONCLUSIONS: The NETest is an accurate diagnostic for GEPNEN and BPNEN. It exhibits tumor biology correlation with grading, staging, and progression. CgA as a biomarker is significantly less accurate than NETest. The NETest has substantial clinical utility that can facilitate patient management.

Differences between Well-Differentiated Neuroendocrine Tumors and Ductal Adenocarcinomas of the Pancreas Assessed by Multi-Omics Profiling.

Most pancreatic neuroendocrine tumors (PNETs) are indolent, while pancreatic ductal adenocarcinomas (PDACs) are particularly aggressive. To elucidate the basis for this difference and to establish the biomarkers, by using the deep sequencing, we analyzed somatic variants across coding regions of 409 cancer genes and measured mRNA/miRNA expression in nine PNETs, eight PDACs, and four intestinal neuroendocrine tumors (INETs). There were 153 unique somatic variants considered pathogenic or likely pathogenic, found in 50, 57, and 24 genes in PDACs, PNETs, and INETs, respectively. Ten and 11 genes contained a pathogenic mutation in at least one sample of all tumor types and in PDACs and PNETs, respectively, while 28, 34, and 11 genes were found to be mutated exclusively in PDACs, PNETs, and INETs, respectively. The mRNA and miRNA transcriptomes of PDACs and NETs were distinct: from 54 to 1659 differentially expressed mRNAs and from 117 to 250 differentially expressed miRNAs exhibited high discrimination ability and resulted in models with an area under the receiver operating characteristics curve (AUC-ROC) >0.9 for both miRNA and mRNA. Given the miRNAs high stability, we proposed exploring that class of RNA as new pancreatic tumor biomarkers.

Primarily resectable pancreatic adenocarcinoma - to operate or to refer the patient to an oncologist?

The aim of this work is to investigate the optimal therapeutic sequence of resectable pancreatic cancer - primary surgery with adjuvant therapy or neoadjuvant followed by resection. Application of the neoadjuvant approach in routine treatment of pancreatic cancer is rapidly growing every year, despite the lack of final results from randomized trials. Recent advancements in the adjuvant therapy, due to the more effective chemotherapy regimens, favor the upfront surgery strategy. On the other hand, theoretical background and metaanalyses favor the neoadjuvant strategy. Currently, primary resection with adjuvant chemotherapy remains the standard approach in resectable pancreatic cancer, but the first recommendations considering the neoadjuvant approach as an option seem to arise among the scientific societies with a global impact. Preliminary results of Prodige 24 study and PREOPANC-1 trial demonstrates that both options are worth further evaluation in clinical trials. Their results should soon provide more answers to this important clinical questions.

Pancreaticopleural and pancreaticomediastinal fistula extending to the cervical region, with dysphagia as initial symptom: A case report.

RATIONALE: Pancreaticopleural and pancreaticomediastinal fistulas are rare complications of pancreatitis. They are often misdiagnosed and there are no strict guidelines of treatment. In this study, we present a brief report of a combined pancreaticopleural and pancreaticomediastinal fistula extending to the cervical region, causing dysphagia and cervical swelling as initial symptoms. PATIENT CONCERNS: A 36-year-old female with history of alcohol abuse and pancreatitis presented progressing dysphagia and mild dyspnea on admission. DIAGNOSIS: Chest X-ray and chest and abdominal computed tomography scan (CT) indicated pancreaticopleural fistula combined with pancreaticomediastinal fistula, a diagnosis confirmed by high amylase levels in pleural fluid. INTERVENTIONS: Conservative treatment was administered and ERCP was performed but pancreatic duct stenting was impossible. The patient presented rapid anterior cervical swelling with progressing dysphagia and dyspnea. CT showed fistula penetration to the cervical region. The patient underwent urgent surgery and pancreaticojejunal anastomosis was performed. OUTCOMES: The surgery led to recovery. Six months later, the patient reported good health and weight gain. LESSONS: Coexistence of pancreaticopleural and pancreaticomediastinal fistula with cervical penetration is an extremely rare pancreatitis complication. It presents with dysphagia and anterior cervical swelling as initial symptoms. It is important to consider this complication in all patients with history of pancreatitis, presenting with dysphagia.

Roux-en-Y duodenojejunostomy improves gastric emptying in experimental obstruction of the distal duodenum.

INTRODUCTION: We undertook a comparative survey of gastric emptying (GE) kinetics after two variants of bypass surgery for upper bowel obstruction. MATERIAL & METHODS: In 10 dogs with experimental upper bowel obstruction, five were randomized to obtain gastrojejunal anastomosis (GA), and the other five received Roux-en-Y duodenojejunal anastomosis (DA). Duplicate scintigraphic measurements of GE of a solid meal were accomplished in every animal before surgery and during the early (2-3 weeks), medium (3 months), and late (6 months) post-operative period. The GE curves were fitted with a power-exponential function to derive the GE half time T½, and the curve shape parameter S. RESULTS: Early after surgery T½ slightly decreased by -18±21 min in the DA group and lengthened by 91±37 min in the GA group (p = 0.042). In both groups an increase in the S parameter was found then. In either group T½ gradually declined towards the basal value during the medium and late post-operative period. On the other hand, net differences relative to the basal situation in the S values appeared to be positive in the GA group (0.32±0.11 at 3 months; 0.64±0.19 at six months), and negative in the DA group (-0.30±0.09 at 3 months; -0.01±0.20 at six months). Hence a statistically significant contrast was found between those differences: p = 0.0022 at 3 months, and p = 0.045 at six months after the surgery. CONCLUSION: Roux-en-Y duodenojejunal anastomosis appears to be superior to the classical gastrojejunal anastomosis while restoring patency of the gastrointestinal passage in the case of upper bowel obstruction.