Heterotopic pancreas: typical and atypical imaging findings

An ensemble machine learning model assists in the diagnosis of gastric ectopic pancreas and gastric stromal tumors

OBJECTIVE

To develop an ensemble machine learning (eML) model using multiphase computed tomography (MPCT) for distinguishing between gastric ectopic pancreas (GEP) and gastric stromal tumors (GIST) in lesions < 3 cm.

METHODS

In this study, we retrospectively collected MPCT images from 138 patients between April 2017 and June 2023 across two centers. Cohort 1 comprised 94 patients divided into a training cohort and an internal validation cohort, while the 44 patients from Cohort 2 constituted the external validation cohort. Deep learning (DL) models were constructed based on the lesion region, and radiomics features were extracted to develop radiomics models, which were later integrated into the fusion model. Model performance was assessed through the analysis of the area under the receiver operating characteristic curve (AUROC). The diagnostic efficacy of the optimal model was compared with that of a radiologist. Additionally, the radiologist with the assistance of the eML model provides a secondary diagnosis, to assess the potential clinical value of the model.

RESULTS

After evaluation using an external validation cohort, the radiomics model demonstrated the highest performance in the venous phase, achieving AUROC of 0.87. The DL model showed optimal performance in the non-contrast phase, with AUROC of 0.81. The eML achieved the best performance across all models, with AUROC of 0.90. The use of eML-assisted analysis resulted in a significant improvement in the junior radiologist's accuracy, rising from 0.77 to 0.93 (p < 0.05). However, the senior radiologist's accuracy, while improving from 0.86 to 0.95, did not exhibit a statistically significant difference.

CONCLUSION

eML model based on MPCT can effectively distinguish between GEPs and GISTs < 3 cm.

CRITICAL RELEVANCE STATEMENT

The multiphase CT-based fusion model, incorporating radiomics and DL technology, proves effective in distinguishing between GEP and gastric stromal tumors, serving as a valuable tool to enhance diagnoses and offering references for clinical decision-making.

KEY POINTS

No studies yet differentiated these tumors via radiomics or DL. Radiomics and DL methodologies unveil potentially distinct phenotypes within lesions. Quantitative analysis on CT for GIST and ectopic pancreas. Ensemble learning aids accurate diagnoses, assisting treatment decisions.

Heterotopic pancreas in the gallbladder: A case report

BACKGROUND

Heterotopic pancreas (HP) refers to pancreatic tissue located in areas with no vascular or anatomical connection to the pancreas. HP occurs mostly in the stomach, duodenum, and colon, and rarely in the gallbladder.

CASE SUMMARY

A 57-year-old woman was referred to our hospital complaining of right upper quadrant discomfort for 3 years. An abdominal computed tomography scan revealed adenomyomatosis with a thickened fundus of the gallbladder. The patient underwent a laparoscopic cholecystectomy, and pathological examination unexpectedly showed heterotopic pancreatic tissue in the gallbladder. The patient had a favorable recovery and was discharged on postoperative day 3. She did not report any symptoms or complications at the 6-mo postoperative follow-up. Pathologists should pay close attention to such pancreatic tissue and carefully examine it for dysplasia or malignancy.

CONCLUSION

This case provides more information about HP in the gallbladder, a rare occurrence.

Clinical features and treatment of heterotopic pancreas in children: a multi-center retrospective study

OBJECTIVE

Heterotopic pancreas, an uncommon condition in children, can present with diagnostic and treatment challenges. This study aimed to evaluate the clinical features and treatment options for this disorder in pediatric patients.

METHODS

We conducted a retrospective analysis, including patients diagnosed with heterotopic pancreas at four tertiary hospitals between January 2000 and June 2022. Patients were categorized into symptomatic and asymptomatic groups based on clinical presentation. Clinical parameters, including age at surgery, lesion size and site, surgical or endoscopic approach, pathological findings, and outcome, were statistically analyzed.

RESULTS

The study included 88 patients with heterotopic pancreas. Among them, 22 were symptomatic, and 41 were aged one year or younger. The heterotopic pancreas was commonly located in Meckel's diverticulum (46.59%), jejunum (20.45%), umbilicus (10.23%),ileum (7.95%), and stomach (6.82%). Sixty-six patients had concomitant diseases. Thirty-three patients had heterotopic pancreas located in the Meckel's diverticulum, with 80.49% of cases accompanied by gastric mucosa heterotopia (GMH). Patients without accompanying GMH had a higher prevalence of heterotopic pancreas-related symptoms (75%). Treatment modalities included removal of the lesions by open surgery, laparoscopic or laparoscopic assisted surgery, or endoscopic surgery based on patient's age, the lesion site and size, and coexisting diseases.

CONCLUSIONS

Only one-fourth of the patients with heterotopic pancreas presented with symptoms. Those located in the Meckel's diverticulum have commonly accompanying GMH. Open surgical, laparoscopic surgical or endoscopic resection of the heterotopic pancreas is recommended due to potential complications. Future prospective multicenter studies are warranted to establish rational treatment options.

Adenocarcinoma developing from gastric heterotopic pancreas: a case report and short review

Heterotopic pancreas is a relatively rare condition that may be associated to clinical complaints or signs. Here, we report a case of gastric heterotopic pancreas assictaed to ductal adenocarcinoma. Obstructive jaundice was the initial symptom prompting medical intervention. A 73-year-old male patient presented with yellow staining of the skin and sclera, and dull epigastric pain. Contrast-enhanced computed tomography showed stenosis of the extrahepatic distal bile duct and mass lesions of the antrum. The patient underwent tumor resection, distal gastrectomy (Billroth II), and common bile duct exploration. Postoperative pathological examination revealed an adenocarcinoma located in the wall of the gastric antrum. Immunohistochemical results suggested that the tumor originated from the pancreas. Heterologous pancreatic tissue and a dilated pancreatic duct were found in the tumor. These findings suggest malignant transformation of the gastric heterotopic pancreas. Of note, jaundice as clinical complaint for adenocarcinoma associated to gastric heterotopic pancreas.

Heterotopic Pancreas: Unusual Cause of Usual Diarrhoea

Heterotopic pancreas (HP) also known as ectopic pancreas, pancreatic crest or accessory pancreas is the normal pancreatic tissue, found in a remote area other than its natural location, with no anatomic or vascular connection to main pancreatic tissue. It is a rare congenital anomaly and has been reported at many locations such as stomach (antrum) and small intestine. HP is usually an incidental finding and asymptomatic, however there are reports of pancreatitis, obstruction, perforation and malignant transformation as uncommon manifestations. Diagnosis of HP is primarily based on histological examination either by biopsy or surgical excision. Surgery is the standard treatment for symptomatic HP patients. Herein, we present a case of a 58-year-old female, who presented to us with intractable diarrhoea due to HP in the jejunum and underwent minimally invasive surgery for definitive diagnosis and treatment.

Development of a multi-phase CT-based radiomics model to differentiate heterotopic pancreas from gastrointestinal stromal tumor

BACKGROUND

To investigate whether CT-based radiomics can effectively differentiate between heterotopic pancreas (HP) and gastrointestinal stromal tumor (GIST), and whether different resampling methods can affect the model's performance.

METHODS

Multi-phase CT radiological data were retrospectively collected from 94 patients. Of these, 40 with HP and 54 with GISTs were enrolled between April 2017 and November 2021. One experienced radiologist manually delineated the volume of interest and then resampled the voxel size of the images to 0.5 × 0.5 × 0.5 mm3, 1 × 1 × 1 mm3, and 2 × 2 × 2 mm3, respectively. Radiomics features were extracted using PyRadiomics, resulting in 1218 features from each phase image. The datasets were randomly divided into training set (n = 66) and validation set (n = 28) at a 7:3 ratio. After applying multiple feature selection methods, the optimal features were screened. Radial basis kernel function-based support vector machine (RBF-SVM) was used as the classifier, and model performance was evaluated using the area under the receiver operating curve (AUC) analysis, as well as accuracy, sensitivity, and specificity.

RESULTS

The combined phase model performed better than the other phase models, and the resampling method of 0.5 × 0.5 × 0.5 mm3 achieved the highest performance with an AUC of 0.953 (0.881-1), accuracy of 0.929, sensitivity of 0.938, and specificity of 0.917 in the validation set. The Delong test showed no significant difference in AUCs among the three resampling methods, with p > 0.05.

CONCLUSIONS

Radiomics can effectively differentiate between HP and GISTs on CT images, and the diagnostic performance of radiomics is minimally affected by different resampling methods.

A CT-based nomogram established for differentiating gastrointestinal heterotopic pancreas from gastrointestinal stromal tumor: compared with a machine-learning model

OBJECTIVE

To identify CT features and establish a nomogram, compared with a machine learning-based model for distinguishing gastrointestinal heterotopic pancreas (HP) from gastrointestinal stromal tumor (GIST).

MATERIALS AND METHODS

This retrospective study included 148 patients with pathologically confirmed HP (n = 48) and GIST (n = 100) in the stomach or small intestine that were less than 3 cm in size. Clinical information and CT characteristics were collected. A nomogram on account of lasso regression and multivariate logistic regression, and a RandomForest (RF) model based on significant variables in univariate analyses were established. Receiver operating characteristic (ROC) curve, mean area under the curve (AUC), calibration curve and decision curve analysis (DCA) were carried out to evaluate and compare the diagnostic ability of models.

RESULTS

The nomogram identified five CT features as independent predictors of HP diagnosis: age, location, LD/SD ratio, duct-like structure, and HU lesion/pancreas A. Five features were included in RF model and ranked according to their relevance to the differential diagnosis: LD/SD ratio, HU lesion/pancreas A, location, peritumoral hypodensity line and age. The nomogram and RF model yielded AUC of 0.951 (95% CI: 0.842-0.993) and 0.894 (95% CI: 0.766-0.966), respectively. The DeLong test found no statistically significant difference in diagnostic performance (p > 0.05), but DCA revealed that the nomogram surpassed the RF model in clinical usefulness.

CONCLUSION

Two diagnostic prediction models based on a nomogram as well as RF method were reliable and easy-to-use for distinguishing between HP and GIST, which might also assist treatment planning.

Pancreatic adenocarcinoma arising from an ectopic pancreas in a cat

An 8-year-old male neutered Korean shorthair cat presented with chronic vomiting. Radiographically, an oval-shaped soft tissue abdominal mass caudoventral to the left kidney was detected. On ultrasonography, the hypoechoic mass was well-defined with thick, irregular, and hyperechoic margins and had no continuity with the pancreas or other adjacent organs. The mass was surgically excised. Areas of atypical pancreatic acinar epithelial cells were identified histopathologically. Postoperative CT demonstrated a normal pancreas in the expected anatomical region. Based on diagnostic imaging, surgical and histopathology findings, the mass was diagnosed as a well-differentiated pancreatic acinar cell adenocarcinoma arising from ectopic pancreatic tissue.

Acute peritonitis caused by the acute pancreatitis of an ectopic pancreas in a jejunal duplication, in an adult with intestinal malrotation: a case report

BACKGROUND

Intestinal duplication and ectopic pancreas are two rare independent congenital anomalies. Few reports describe cases of patients with ectopic pancreas in an intestinal duplication causing acute peritonitis.

CASE PRESENTATION

A 31-year-old man was admitted to the hospital for epigastric pain. The patient was diagnosed with acute peritonitis caused by the acute pancreatitis of an ectopic pancreas in a jejunal duplication, with intestinal malrotation. The patient underwent the partial resection of the jejunum and Ladd's procedure. The histopathological findings indicated ectopic pancreatitis in the jejunal duplication.

CONCLUSIONS

We presented the case of acute peritonitis caused by the acute pancreatitis of an ectopic pancreas in a jejunal duplication in an adult with intestinal malrotation. Surgery is the primary treatment and is necessary for a definitive diagnosis.

Expression and clinicopathological characteristics of PDX1, PTF1A, and SALL4 in large and small ducts of ectopic pancreas located in gastro-duodenum and jejunum

An ectopic pancreas is defined as pancreatic tissue outside its normal location, anatomically separated from the pancreas. The transcription factor pancreas/duodenum homeobox protein 1 (PDX1) is involved in maintaining the pancreas and functions in early pancreatic development, beta cell differentiation, and endocrine non beta cells. Pancreatic transcription factor 1 subunit alpha (PTF1A) affects exocrine cell formation and regulation of acinar cell identity, and is expressed in exocrine cells as a transcription factor. The depletion of SALL4 disrupts self-renewal and induces differentiation. To clarify which of PDX1, PTF1A, or SALL4 determines the difference in Heinrich's classification, we examined the localization and number of positive cells. We analyzed the differential expression of PDX1, PTF1A, and SALL4 in large and small ducts in ectopic pancreas by immunohistochemistry. Results showed that the number of PTF1A-positive cells in large ducts was more widespread in type I than in type II in the gastro-duodenum, and more SALL4-positive cells were noticed in large ducts than in small ducts in the gastro-duodenum of type II. Our results revealed that PTF1A might promote exocrine differentiation in developing the pancreatic tissues, and that those with widespread expression differentiate into exocrine cells.

Cystic dystrophy in heterotopic pancreas

Cystic dystrophy in heterotopic pancreas, or paraduodenal pancreatitis, is a rare and complicated presentation involving heterotopic pancreatic tissue in the duodenal wall. This condition is present in 5% of the general population but disease mainly affects middle-aged alcoholic-smoking men with chronic pancreatitis (CP). It may be purely duodenal or segmental (pancreatico-duodenopathy). Its pathophysiology arises from alcohol toxicity with obstruction of small ducts of heterotopic pancreatic tissue present in the duodenal wall and the pancreatic-duodenal sulcus, leading to repeated episodes of pancreatitis. The symptomatology includes episodes of acute pancreatitis, weight loss, and vomiting due to duodenal obstruction. Imaging shows thickening of the wall of the second portion of the duodenum with multiple small cysts. A stepwise therapeutic approach is preferred. Conservative medical treatment is favored in first intention (analgesics, continuous enteral feeding, somatostatin analogues), which allows complete symptomatic regression in 57% of cases associated with a 5% rate of complications (arterial thrombosis and diabetes). Endoscopic treatment may also be associated with conservative measures. Surgery achieves a complete regression of symptoms in 79% of cases but with a 20% rate of complications. Surgery is indicated in case of therapeutic failure or in case of doubt about a malignant tumor. Pancreaticoduodenectomy and duodenal resection with pancreatic preservation (PPDR) seem to be the most effective treatments. PPDR has also been proposed as a first-line treatment for purely duodenal location of paraduodenal pancreatitis, thereby preventing progression to an extended segmental form.

Gastric outlet obstruction caused by heterotopic pancreas in a patient with alcohol use disorder

INTRODUCTION AND IMPORTANCE

Heterotopic Pancreas (HP) is defined by the presence of pancreatic tissue in an anatomically distinct location from the main pancreas. While often clinically silent, it may present symptomatically. If located in the gastric antrum, HP may cause gastric outlet obstruction (GOO). The objective of this paper is to present a rare case of HP in the gastric antrum causing GOO.

CASE PRESENTATION

Herein, we report a 43-year-old man who presented with abdominal pain and non-bilious emesis in the setting of COVID-19 infection and alcohol consumption. During the initial workup, computed-tomography (CT) was non-specific but demonstrated GOO, concerning for cancer. Cold forceps biopsies taken during esophagogastroduodenoscopy (EGD) confirmed benign HP. Since the patient was symptomatic from gastric outlet compression, he underwent resection via laparoscopic distal gastrectomy and Billroth II gastrojejunostomy. At 1-month postoperative follow-up, the patient recovered uneventfully. We hypothesized that GOO by HP in this case may have been associated with cumulative effects of alcohol consumption and COVID-19 infection on the ectopic tissue.

CLINICAL DISCUSSION

HP is rare and difficult to diagnose preoperatively. When located in gastric antrum, HP can cause GOO, mimicking gastric malignancy. Combination of EGD/EUS, biopsy/FNA, and surgical resection are necessary to definitively make the diagnosis. Finally, it is important to consider that heterotopic pancreatitis or structural changes in HP may occur due to classic pancreatic stressors like alcohol and viral infections.

CONCLUSION

HP may cause GOO presenting with non-bilious emesis and abdominal pain, mistaken for malignancy on CT imaging.

Localization and Laparoscopic Excision of Gastric Heterotopic Pancreas in a Child by Endoscopic SPOT® Tattooing

Heterotopic pancreas (HP) is defined as pancreatic tissue lacking vascular or anatomic connection with the normal pancreas. Surgical resection is often indicated for symptomatic gastric HP. However, intraoperative identification of gastric HP is often difficult during laparoscopic surgery. Herein, we describe a patient with gastric HP, which was marked with SPOT^® dye (GI Supply, Camp Hill, PA, USA). The dye was seen clearly laparoscopically facilitating total excision of the lesion. The final pathology report confirmed the presence of heterotopic pancreatic tissue including pancreatic acini, small pancreatic ducts tissue with islets of Langerhans in the deep gastric submucosal area. There were no postoperative complications, and the patient was symptom-free. To the best of our knowledge, this was the first case report in the literature in which endoscopic tattooing of gastric HP before laparoscopic resection was performed. This method of localization was simple and reliable in children.

Gastric ectopic pancreas in magnetic resonance imaging: A review of 2 cases

Gastric ectopic pancreas (EP) is an uncommon congenital anomaly in which pancreatic tissue with no anatomic connection to the main pancreas is found in the stomach. Gastric EP is often discovered incidentally when a nonspecific submucosal tumor is found in endoscopic studies or other imaging examinations. Tissue characterization by biopsy or fine-needle aspiration is required as endoscopic findings alone cannot exclude malignancy. The authors present 2 cases of gastric EP incidentally detected on endoscopy, which underwent further characterization by magnetic resonance imaging (MRI). In both cases, MRI showed submucosal gastric lesions, isointense to the orthotopic pancreas in all sequences, including hyperintensity on T1-weighted images. Furthermore, the lesions showed bright arterial phase enhancement, paralleling the native pancreas. MRI may provide the best non-invasive imaging method for evaluating gastric submucosal lesions. This report intends to show that EP shows a characteristic MR appearance that allows differentiation from other submucosal lesions.

Radiologic Review of Small Bowel Malignancies and Their Mimicking Lesions

Because of their small size, small bowel malignancies are often easily missed when radiologists read CT images, which can lead to errors in the normal small bowel due to their similar enhancement to the small bowel or non-specific enhancement. In addition, small bowel malignancies are sometimes mistaken for masses of other origins, such as the uterus, rectum, or omentum. In this article, we describe various small-bowel malignancies, their mimicking lesions and the typical and atypical features on CT imaging along with their clinical manifestations.

Case report of retroperitoneal ectopic pancreas with adrenal adenoma

Background

Ectopic pancreas is a congenital anomaly in which pancreatic tissue is anatomically separated from the main gland and without vascular or ductal continuity. A case of retroperitoneal ectopic pancreas with adrenal adenoma has never yet been reported.

Case Presentation

A 54-year-old man presented three masses in the left retroperitoneum, and two of them were resected. The pathologic findings were a retroperitoneal ectopic pancreas with adrenal adenoma.

Conclusion

We report an extremely rare case of a retroperitoneal ectopic pancreas and its characterization with dynamic gadolinium-enhanced magnetic resonance imaging (MRI).

Pancreatic Heterotopia in the Small Bowel: A Case Report and Literature Review

ABSTRACT

Diagnosing pancreatic heterotopia (PH) is challenging, because it is a rare congenital anomaly. We report the case of a 66-year-old man who presented with ileus and jejunal PH diagnosed using single-balloon enteroscopy. Reviewing 178 cases of small intestinal PH in the literature showed that (1) PH mostly occurred at the duodenum (61.8%), followed by the jejunum (22.5%) and ileum (14.6%); (2) patients with ileal PH were younger (mean, 40.7 vs 54.6 years; P < 0.001), while those with jejunal PH were older (mean, 59.5 vs 51.7 years; P = 0.006); (3) most patients with jejunal PH were females, while those with duodenal or ileal PH were predominantly males (M:F = 0.8:1 vs 2.5:1; P = 0.003); (4) asymptomatic cases were rare (15.2% vs 83.4% in small and nonsmall bowel, respectively); (5) most patients with ileal PH presented with bleeding (61.5%), while the remaining had abdominal pain (42.8%); (6) emergent operation was performed in 11 cases (6.2%), mainly at the jejunum (12.5%) and Meckel's diverticulum (25%); and (7) Heinrich's classification may be inconclusive. Enteroscopy was performed in only 6 cases (3.4%), and earlier diagnosis and further minimally invasive procedures could have been achieved with enteroscopy.

Laparoscopic surgery for duodenal perforation due to a diverticulum with heterotopic pancreas: a case report

BACKGROUND

Heterotopic pancreas (HP) refers to the presence of abnormally located pancreatic tissue without any anatomic or vascular continuity with the main body of the pancreas. HP can occur in the gastrointestinal tract and be complicated by gastrointestinal bleeding, pancreatitis, obstruction, or malignant generation. Specifically, perforation of the gastrointestinal tract because of HP is extremely rare.

CASE PRESENTATION

A 91-year-old woman was diagnosed with duodenal perforation, and an emergency laparoscopic operation was performed. The operative findings indicated a tumor and duodenal wall perforation. The tumor and the perforated site were resected with a linear stapler. Histopathological examination revealed the presence of HP tissue in the submucosal layer around the diverticulum without any signs of inflammation. The perforated site was not covered by HP tissues, and the duodenal wall might have been weaker than the other areas, which could have caused the internal pressure to increase and led to the perforation.

CONCLUSIONS

Preoperative HP diagnosis is difficult, and it is crucial to consider HP as the differential diagnosis in gastrointestinal perforations. The duodenal diverticula can be perforated due to increased internal pressure of the duodenum caused by the imbalanced localization of HP.

Malignant transformation of heterotopic pancreas as middle esophagus adenocarcinoma—A rare case report and comprehensive literature review

Heterotopic pancreas is a rare congenital abnormality that occurs during the growth and development process. It can be found in any part of the digestive tract, but the most common sites are the stomach, duodenum, and jejunum. Malignant transformation especially in the esophagus is rare. Here, we aim to report an unusual case of mid‐esophageal adenocarcinoma that originated from a heterotopic pancreas.

Insight into gastrointestinal heterotopic pancreas: imaging evaluation and differential diagnosis

Heterotopic pancreas (HP) is an uncommon congenital abnormality in the developmental process of the pancreas, with gastrointestinal heterotopic pancreas (GHP) being the most common HP. The clinical manifestations of GHP may have variable patterns of presentation, dictated by both the anatomic location and the functional ability of the lesion. The most common imaging modality in detecting GHP is computed tomography (CT), while gastrointestinal barium fluoroscopy, endoscopic ultrasonography, and magnetic resonance imaging (MRI) are also applied. The density and enhancement patterns of GHP are consistent with histological classifications. GHP with a predominantly acinar tissue component manifests homogeneous and marked enhancement on CT images, whereas a predominantly ductal GHP presents heterogeneous and mild enhancement. On MRI, the appearance and signal intensity of GHP were paralleled to the normal pancreas on all sequences and were characterized by T1-weighted high signal and early marked enhancement. This article provides a comprehensive review of the histopathology, clinical manifestations, imaging features of various modalities, and differential diagnosis of GHP. It is hoped that this review will improve clinicians' knowledge of GHP and aid in accurate preoperative diagnosis, thereby reducing the misdiagnosis rate.

Incidental Jejunal Lesion Necessitating Intraoperative Change of Plan During Bariatric Surgery: a Video Case Report

Incidental gastric and small bowel lesions are commonly encountered during bariatric surgery. Resection of these lesions with negative margins in the same sitting is curative; however, this may necessitate intraoperative change of plan. We present a 44-year-old super obese lady in whom an exophytic jejunal mass was found at 80 cm from the ligament of Treitz, which necessitated a change of procedure from one anastomosis gastric bypass (OAGB) to Roux-en-Y gastric bypass (RYGB). The final pathology was ectopic pancreatic tissue. Running the small bowel during initial diagnostic laparoscopy should be a routine step before division of stomach, to avoid technical complexities when operative plan is changed in order to resect an incidentaloma. Bariatric surgeons should be well versed with all the standard bariatric procedures.

Malignant Transformation of Heterotopic Pancreatic Tissue in a Patient with BRCA2 Mutation

Background: Malignant transformation of heterotopic pancreatic tissue is a rare entity with only several case reports published in the scientific literature. Adjuvant chemotherapy following oncological resection for lesions with nodal metastasis has not been well described and there are no guidelines available to guide the management of these patients. Case Presentation: We present a case of gastric heterotopic pancreatic carcinoma with nodal metastasis in a young patient with breast cancer gene (BRCA) 2 mutation. He had undergone a laparoscopic wedge resection for a gastric lesion initially thought to be a gastrointestinal stroma tumor. Given the involvement of the wedge resection margins, the patient underwent a distal gastrectomy with oncological lymph nodal clearance. One out of the 33 harvested lymph nodes harboured micrometastasis while the main gastrectomy specimen did not have any residual malignancy. Following the histological diagnosis, he received an adjuvant chemotherapy regime akin to that prescribed for locally advanced pancreatic adenocarcinoma with good response. This is, to our knowledge, also the first such case report in a patient with BRCA2 mutation. Conclusions: Pre-operative diagnostic confirmation is challenging and endoscopic procedures pose significant false negatives. Reports of nodal metastasis following oncological resection are limited and there are no guidelines regarding adjuvant therapies. We would recommend a chemotherapy regimen similar to that for primary locally advanced pancreatic carcinoma in patients found to have nodal metastasis.

Use of computed tomography for distinguishing heterotopic pancreas from gastrointestinal stromal tumor and leiomyoma

PURPOSE

To determine whether morphologic features and semiquantitative parameters of computed tomography (CT) could be used to distinguish heterotopic pancreas from gastrointestinal stromal tumor (GIST) and leiomyoma.

METHODS

This retrospective study evaluated CT images of heterotopic pancreases (n = 28), GISTs (n = 57), and leiomyomas (n = 26) located in the upper gastrointestinal tract. Morphologic imaging features of lesions were analyzed, including location, contour, margin, attenuation, growth pattern, enhancement type, enhancement degree, enlarged vessels feeding or draining the mass, hyperenhancement of the overlying mucosa, low intralesional attenuation, calcification, and a duct-like structure. Semiquantitative parameters included long diameter (LD), short diameter (SD), LD/SD ratio, and lesion and aorta CT values during plain CT (Lp and Ap), arterial phase (La and Aa), and venous phase (Lv and Av). Diagnostic performance of these findings and parameters were evaluated by receiver operating characteristic (ROC) analysis.

RESULTS

Morphologic CT findings (including lesion contour, margin, attenuation, growth pattern, enhancement type, and enhancement degree) and semiquantitative parameters except for LD/SD were demonstrated to be significant for differentiating heterotopic pancreas from GIST and leiomyoma (all P < 0.01). Of these, location, low intralesional attenuation, duct-like structure and LD, SD, Lv, and Sv values showed good diagnostic performance with the areas under curve (AUC) higher than 0.70. The presence of a duct-like structure demonstrated the best diagnostic ability with AUC of 0.929 [95% confidence interval (CI) 0.864-0.969], sensitivity of 5.7% (95% CI 67.3-96.0), and specificity of 100% (95% CI 95.7-100), respectively. When the three morphologic features (location, low intralesional attenuation, duct-like structure) were used in combination, the AUC was improved to 0.980 (95% CI 0.952-1).

CONCLUSION

CT features, especially the morphologic features, could be used to differentiate heterotopic pancreas from GIST and leiomyoma in the upper gastrointestinal tract and, thus, provide a more accurate method for non-invasive preoperative diagnosis. Additionally, the presence of a duct-like structure demonstrated to be a reliable indicator for heterotopic pancreas among the morphologic and semiquantitative CT features.

Intramural ectopic pancreatic tissue of the stomach: A case report of an uncommon origin of a non-cancerous gastric tumour

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Ectopic pancreatic tissue is a rare incidental finding during abdominal surgery.

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80% of the lesions are unifocal and less than 3 cm in size.

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The most frequent site is the stomach, followed by duodenum and proximal jejunum.

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The imaging modalities and endoscopic biopsy often remain inconclusive.

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Only resection and and histopathologic examination provide the definitve diagnosis.

Introduction

Ectopic pancreatic tissue is often incidentally encountered during abdominal surgery. We report a case of an incidental finding during a laparoscopic appendectomy, the approach to diagnosis and management of this.

The work has been reported in line with the SCARE criteria.

Presentation of case

A 32 year-old woman was diagnosed with an intramural pre-pyloric mass during a laparoscopic appendectomy. The lesion was identified on a subsequent computed tomography as a homogenous mass on the greater curvature. Upper esophagho-gastro-duodenoscopy was normal. The intramural mass was confirmed by an endoscopic sonography and the fine needle biopsy showed aspecific inflammatory cells. A laparoscopic wedge resection was realized. Histopathologic examination confirmed the diagnosis of an ectopic pancreatic tissue.

Discussion

The management of ectopic pancreas poses a medical challenge. The diagnostic quiver consists of radiologic exams and endoscopy, in combination with a direct biopsy of the lesion.

Conclusion

Despite the plethora of diagnostic modalities available, a definitive diagnosis for heterotopic pancreas often remains elusive, requiring more invasive diagnostic means. Although ample information is available in literature, there are currently no evidence-based guidelines regarding diagnosis and management of heterotopic pancreas.

Nesidioblastosis Associated with Pancreatic Heterotopia as a Differential Diagnosis of Hypoglycemia: A Literature Review and Case Report

Patient: Male, 32-year-old

Final Diagnosis: Nesidioblastosis

Symptoms: Hypoglycemia

Medication:—

Clinical Procedure: Distal pancreatectomy • magnetic resonance image • selective arterial calcium stimulation test with hepatic venous sampling

Specialty: Endocrinology and Metabolic

Pancreatitis in the developmentally anomalous pancreas

Developmental anomalies of the pancreas include more common entities such as pancreas divisum and annular pancreas, and unusual entities such as heterotopic pancreas. While these anomalies can present a diagnostic challenge to the radiologist, when the pancreatic tissue involved in these processes develops pancreatitis, the radiographic appearance can present a diagnostic dilemma. Awareness of these pancreatic anomalies and familiarity with their appearance when inflamed is necessary to distinguish pancreatitis in the developmentally anomalous pancreas from other inflammatory or neoplastic processes.

Loss of GATA4 causes ectopic pancreas in the stomach

Pancreatic heterotopia is defined as pancreatic tissue outside its normal location in the body and anatomically separated from the pancreas. In this work we have analyzed the stomach glandular epithelium of Gata4 ^flox/flox ; Pdx1-Cre mice (Gata4KO mice). We found that Gata4KO glandular epithelium displays an atypical morphology similar to the cornified squamous epithelium and exhibits upregulation of forestomach markers. The developing gastric units fail to form properly, and the glandular epithelial cells do not express markers of gastric gland in the absence of GATA4. Of interest, the developing glands of the Gata4KO stomach express pancreatic cell markers. Furthermore, a mass of pancreatic tissue located in the subserosa of the Gata4KO stomach is observed at adult stages. Heterotopic pancreas found in Gata4-deficient mice contains all three pancreatic cell lineages: ductal, acinar, and endocrine. Moreover, Gata4 expression is downregulated in ectopic pancreatic tissue of some human biopsy samples. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Heterotopic pancreas in the gastrointestinal tract in children: a single-center experience and a review of the literature

Background

Heterotopic pancreas, that is the abnormal localization of a well-differentiated pancreatic tissue, is a rare occurrence in pediatric patients. Most lesions are found incidentally; in some circumstances, the presence of heterotopic pancreas may cause gastrointestinal symptoms, such as obstructive symptoms or bleeding.

Patients and methods

The clinical notes of patients with histological diagnosis of heterotopic pancreas treated at Meyer Children’s Hospital between 2009 and 2017 have been retrospectively examined.

Four variables have been examined: clinical presentation, age at diagnosis, timing of surgery and localization of the heterotopic pancreas. Patients have been classified accordingly.

Results

Fourteen patients were diagnosed with heterotopic pancreas at a single institution. In half cases, heterotopic pancreas caused symptoms that warranted surgical exploration. Symptomatic patients were significantly older than patients in whom heterotopic pancreas was an incidental finding (mean age 9 years and 5 months vs 2 years and 9 months; p = 0.02). Heterotopic pancreas was more frequently found in patients who underwent urgent surgical procedure than in patients who underwent elective surgery (2.61% vs 0.22%; p < 0.0001). In all cases, foci of heterotopic pancreas were resected.

Conclusion

Heterotopic pancreas is usually discovered in the submucosa of the stomach, duodenum and small bowel. Heterotopic tissue may cause symptoms related to mechanical complications, bleeding from the surrounding intestinal mucosa or, occasionally, to the development of malignancy.

Heterotopic tissue is a rare but clinically relevant cause of gastrointestinal symptoms. The presence of heterotopic tissue should be considered in children with gastrointestinal symptoms of unclear origin and surgical resection is advisable.

Ectopic pancreas in the ileum: An unusual condition and our experience

BACKGROUND

Ectopic pancreas in the ileum, including lesions within Meckel diverticulum, can cause severe manifestations and complications; yet, it was seldom reported in English literature.

AIM

This study aimed to raise awareness and provide information for better clinical management of this rare yet serious condition.

METHODS

A total of 1713 cases of small bowel resection were performed in our hospital between 2009 and 2018, among which 10 cases of ileac ectopic pancreas were identified. A comprehensive retrospective review of the 10 cases was taken.

RESULTS

Five lesions were located in the ileum wall and 5 were within Meckel diverticulum. Two lesions within Meckel diverticulum were incidental; the remaining 8 lesions were all associated with abdominal pain, gastrointestinal bleeding, and anemia. Of the 5 patients with lesions in the ileum wall, computed tomography uniformly revealed ileoileal intussusceptions with masses as lead points. Capsule endoscopies were performed in 6 cases, of which 3 showed positive findings. Double-balloon enteroscopy was conducted in one case and revealed an ileal diverticulum. Therapeutically, the offending bowel segments were removed, and intussusceptions were restored except for one case in which diverticulectomy was applied. No relapse or sequela was observed in the follow-up.

CONCLUSIONS

Ileac ectopic pancreas can be seen in the ileum wall or Meckel diverticulum. The majority of the lesions found in clinical practice present with abdominal pain, gastrointestinal bleeding, and anemia. Lesions in the ileum wall often cause ileoileal intussusception. Computed tomography, capsule endoscopy, and double-balloon enteroscopy are helpful preoperative examinations. Segmental small bowel resection is the treatment of choice.

A case report and literature review: incidental jejunal ectopic pancreatic tissue in an emergency bowel exploration for suspected intussusception

Heterotopic pancreas (HP) is defined as pancreatic tissue which is an anatomically separate entity from the main pancreas and free from the organ's vascular or ductal continuity. Most cases of HP are asymptomatic and are diagnosed incidentally upon laparotomy or on autopsy. The diagnosis of HP can be extremely difficult. A few imaging modalities which include Magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) may show characteristic features of HP. However, definitive diagnosis is made by histopathology. Conversely, these modalities may not differentiate a malignant neoplasm from a benign mass. Surgical excision is thought to be curative for HP. In this case report, we present a 62-year-old female with acute myelocytic leukemia on induction chemotherapy who developed abdominal pain during her hospital admission and was referred to the general surgery department. Abdominal computed tomography (CT) was done and showed signs of small bowel obstruction, perforation, and overlapping jejunoileal segments suggestive of intussusception. Upon surgical exploration two small bowel perforations were repaired, one iatrogenic and one pathological. On bowel run a jejunal mass was found, excised, and upon histopathology confirmed to be a mixed endocrine and exocrine heterotopic pancreatic choristoma. Definitive diagnosis of heterotopic pancreatic tissue is made by histopathology, and surgical excision is potentially curative. In conclusion, we recommend excising HP if found incidentally upon surgery as the diagnosis of HP and exclusion of neoplasm may not be possible without a histological specimen.

A unique case of ectopic pancreas presenting as jejunal malignance

Ectopic pancreas is defined as pancreatic tissues having no anatomic or vascular connections with the orthotopic pancreas. It is difficult for clinicians to diagnose this disease without performing a histopathological examination because it lacks specific clinical manifestations. This case report is of a 46-year-old woman who presented with epigastric pain. She had elevated serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 72-4 (CA72-4). Abdominal contrast-enhanced computed tomography (CT) revealed a persistently enhanced mass in the proximal jejunum, which was confirmed as ectopic pancreas via histopathological examination. Her serum CEA and CA72-4 levels were restored to normal ranges after resecting the jejunal ectopic pancreas. This is the first reported case of ectopic pancreas causing an elevation in serum CEA and CA-724 levels; this report supports the metaplasia theory and suggests that jejunal masses should be cautiously diagnosed for avoiding unnecessary concerns among patients and their families.

Endoscopic submucosal dissection for gastric ectopic pancreas: a single-center experience

BACKGROUND AND OBJECTIVE

Endoscopic submucosal dissection (ESD) is a minimal invasive technology and could allow "en bloc" resection for superficial gastric tumors. The aim of this study is to evaluate the safety and feasibility of ESD for gastric ectopic pancreas (EP).

METHODS

A total of 93 patients diagnosed with ectopic pancreas who underwent ESD between January 2011 and June 2017 were enrolled. The demographic, clinical, and endoscopic data were collected and analyzed.

RESULTS

The average maximal diameter of lesions was 1.01 (range 0.4-3.0) cm with mean age of patients which was 39.75 (range 15-66) years. Overall, all of procedures en bloc was successful. The median operative time was 76.87 (range 30-160) min. A total of 12 patients experienced complications. In seven patients, bleeding occurred during the operation and was treated using hot biopsy forceps or metal clip. Five cases suffered from pneumoperitoneum which was managed well. The mean length of postoperative hospital stay was 5.7 (range 2-17) days. There was no relapse in any cases during the follow-up.

CONCLUSION

ESD appears to be a safe and feasible approach for curative treatment in gastric ectopic pancreas. Larger studies are needed to identify the role and the outcomes of ESD in another center.

CT features of asymptomatic heterotopic pancreas in jejunal mesentery

Heterotopic pancreas (HP) is localized pancreatic tissue that has no relation to orthotopic pancreas and has its own channel and vascular structures. Usually, the submucosa is located in the upper gastrointestinal tract; mesenteric placement is rarely reported. It is frequently asymptomatic and is detected incidentally in imaging, laparotomies, or autopsies. Rarely, pancreatitis may be the cause of small bowel obstruction, massive gastrointestinal bleeding, and malignant transformation. However, this has usually been reported in localized submucosal HP cases. The imaging findings are typical, and the diagnosis can be verified without the need for a histopathological diagnosis. In this case report, we aimed to present the imaging findings of asymptomatic HP located in the proximal jejunum mesentery of a 44-year-old woman. To avoid unnecessary surgical procedures, the characteristic imaging findings of HP are understood and should be considered in the differential diagnosis of masses seen in the mesentery.

Heterotopic Pancreas: Histopathologic Features, Imaging Findings, and Complications

Heterotopic pancreas is a congenital anomaly in which pancreatic tissue is anatomically separate from the main gland. The most common locations of this displacement include the upper gastrointestinal tract-specifically, the stomach, duodenum, and proximal jejunum. Less common sites are the esophagus, ileum, Meckel diverticulum, biliary tree, mesentery, and spleen. Uncomplicated heterotopic pancreas is typically asymptomatic, with the lesion being discovered incidentally during an unrelated surgery, during an imaging examination, or at autopsy. The most common computed tomographic appearance of heterotopic pancreas is that of a small oval intramural mass with microlobulated margins and an endoluminal growth pattern. The attenuation and enhancement characteristics of these lesions parallel their histologic composition. Acinus-dominant lesions demonstrate avid homogeneous enhancement after intravenous contrast material administration, whereas duct-dominant lesions are hypovascular and heterogeneous. At magnetic resonance imaging, the heterotopic pancreas is isointense to the orthotopic pancreas, with characteristic T1 hyperintensity and early avid enhancement after intravenous gadolinium-based contrast material administration. Heterotopic pancreatic tissue has a rudimentary ductal system in which an orifice is sometimes visible at imaging as a central umbilication of the lesion. Complications of heterotopic pancreas include pancreatitis, pseudocyst formation, malignant degeneration, gastrointestinal bleeding, bowel obstruction, and intussusception. Certain complications may be erroneously diagnosed as malignancy. Paraduodenal pancreatitis is thought to be due to cystic degeneration of heterotopic pancreatic tissue in the medial wall of the duodenum. Recognizing the characteristic imaging features of heterotopic pancreas aids in differentiating it from cancer and thus in avoiding unnecessary surgery. ^© RSNA, 2017.

Diagnosis of Mesenteric Ectopic Pancreas by Secretin-Enhanced Magnetic Resonance Cholangiopancreatography

Ectopic pancreas (EP) is defined as pancreatic tissue found outside its usual anatomical position, with no ductal or vascular communication with the native pancreas.We report the case of a 59-year-old woman with a mesenteric jejunal EP initially suspected on computed tomography and confirmed by secretin-enhanced magnetic resonance cholangiopancreatography.Mesenteric EP is a very rare finding with nonspecific clinical presentation, so that, classic radiological findings have not been well described previously.

Heterotopic pancreatic rests: imaging features, complications, and unifying concepts

OBJECTIVE

The spectrum of pancreatic heterotopia will be reviewed, including clinical features, potential complications, and imaging manifestations. This will also include a review of various entities associated with pancreatic heterotopia such as groove pancreatitis and cystic dystrophy of gastroduodenal heterotopic pancreas. These entities were previously thought of as distinct histopathologic entities but now appear to represent manifestations of pancreatic heterotopia.

CONCLUSION

Pancreatic heterotopia and heterotopic pancreatitis can have a wide range of appearances. Several entities, which were previously thought to be distinct, can be considered manifestations of pancreatic heterotopia and heterotopic pancreatitis.

Heterotopic pancreas: a clinicopathological study of 184 cases from a single high-volume medical center in China

Heterotopic pancreas (HP) is often an incidental finding during operative or endoscopic procedures and described in case reports and small series in the literature. Large clinicopathological studies with a systematic analysis remain lacking. Herein, we identified 184 (0.18%; 184/99 544) consecutive histology-proven HP cases of 89 770 surgical resections and 9774 upper endoscopic biopsies carried out at a single medical center in China. Each case was diagnosed by unequivocal identification of pancreatic acini at a location outside the pancreas. The patients' median age was 49 years (range, 14-82) with a slight female predominance (male/female ratio, 0.94). Clinical presentation at diagnosis was nonspecific. Preoperatively, most (54.9%; 101/184) HP lesions were misdiagnosed. Only 26 HP lesions (14.1%) were correctly diagnosed, all in the stomach except for 1 in the duodenum; 57 (31%) were detected during operative procedures for other conditions. The most frequent location of HP was, in descending order, the stomach (97; 52.7%), small intestine (48; 26%), lesser and greater curvature omentum (18; 10%), spleen and hilar region (5; 2.7%), porta hepatis (2; 1%), gallbladder (1; 0.5%), peridistal esophageal tissue (4; 2.2%), and mesentery (7; 3.8%). The size of HP varied from smaller than 0.5 cm (35.3%), 0.6 to 1 cm (34.8%), to larger than 1.1 cm (29.9%). Because of difficulty in preoperative diagnosis, careful workup for upper gastrointestinal diseases with HP as a differential diagnosis may increase the chance of accurate diagnosis and appropriate patient management.

Ektopinė (heterotopinė) kasa plonosios žarnos pasaite: klinikinio atvejo pristatymas ir literatūros apžvalga

Ektopinė kasa (EK) – reta įgimta anomalija, kai normalus kasos audinys yra už kasos ribų. Heterotopinis kasos audinys plonosios žarnos pasaite yra ypač retai sutinkamas EK tipas. EK dažniausiai aptinkama įvairiose virškinamojo trakto dalyse atsitiktinai.

Paprastai EK yra simptomų nesukelianti anomalija, tačiau kliniškai gali pasireikšti atsiradus komplikacijoms, tokioms kaip uždegimas, kraujavimas, obstrukcija ar supiktybėjus. Simptomų išsivystymas priklauso nuo EK dydžio, lokalizacijos bei patologinių audinio pokyčių, kurie taip pat būdingi ir normaliam kasos audiniui. Operacinis gydymas nėra indikuotinas, nebent esant komplikacijoms, todėl labai svarbi tiksli priešoperacinė diagnozė siekiant išvengti nereikalingų intervencijų.

Mes pristatome retą klinikinį atvejį, kada EK lokalizavosi plonosios žarnos pasaite. Pateikiame paciento kompiuterinės tomografijos tyrimo vaizdus. Šis klinikinis atvejis parodo, kad ektopinis kasos audinys visada turėtų būti įtrauktas į gastrointestinių navikų diferencinę diagnostiką.

Gastric obstruction due to intramural pseudocyst associated with heterotopic pancreas

An unusual case of gastric outlet obstruction caused by a gastric intramural pseudocyst associated with heterotopic pancreas is illustrated. Heterotopic pancreas is defined as the presence of aberrant pancreatic tissue that is anatomically and vascularly distinct from the pancreas itself (Liu et al. Am Surg. 78:E141-3, 2012). Heterotopic pancreatic tissue has been reported in many locations along the gastrointestinal tract, identified most commonly in the stomach where it is usually an asymptomatic anatomic curiosity than a source of clinical concern. We encountered an unusual instance in which heterotopic pancreas in the distal stomach was associated with heterotopic pancreatitis and intramural pseudocyst formation that led to gastric obstruction.

Endoscopic removal of symptomatic gastric heterotopic pancreas: a report of nine cases

AIMS

The aim of this study was to evaluate the efficacy and safety of endoscopic removal of symptomatic gastric heterotopic pancreas (HP).

PATIENTS AND METHODS

From January 2010 to December 2011, 9 patients with suspected symptomatic HP were enrolled in the study. Endoscopic ultrasonography was performed to clarify the HP tissue location and to choose the endoscopic resection method. Endoscopic mucosal resection or endoscopic submucosal dissection was performed to remove the HP tissue. Symptoms in the enrolled patients were assessed before and after endoscopic removal of the HP tissue. Tumor pathology and complications were recorded after the treatment. A standard follow-up was scheduled at 1 week and 2 months after treatment.

RESULTS

Removal of suspected HP with endoscopic mucosal resection or endoscopic submucosal dissection was successful in all 9 cases. Abdominal pain, leukocytosis, and bleeding occurred in 6 patients, 2 patients, and 1 patient, respectively, after treatment and were relieved by symptomatic treatment. There were no other unpredictable complications. The symptoms related to HP, including epigastric pain, bloating, and postprandial fullness, were relieved significantly after the treatment. During follow-up, there was no recurrence of HP in any patient.

CONCLUSIONS

Endoscopic removal appears to be a safe and effective method to treat gastric lesions suspected to be HP with symptoms. The symptoms, such as epigastric pain, bloating, and postprandial fullness were well resolved after endoscopic treatment.

Spectrum of imaging manifestations in non-neoplastic gastric pathologies

This article illustrates a wide spectrum of non-neoplastic gastric pathologies on cross-sectional imaging. Salient features of inflammatory, infectious, vascular, traumatic, and miscellaneous conditions of the stomach have been discussed and imaging clues to reach an accurate diagnosis are stressed upon.