Adenocarcinoma arising in association with gastric heterotopic pancreas: A case report and review of the literature

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.

Aberrant pancreas adenocarcinoma in the stomach: A case report and literature review

RATIONALE

Aberrant pancreatic tissue in the gastrointestinal tract is a relatively common finding. However, malignant transformation is extremely rare. Herein, we report a case of ectopic pancreatic ductal adenocarcinoma in the stomach wall.

PATIENT CONCERNS

A 38 year old male presented with nausea, bloating, abdominal distention and weight loss for 4 months.

DIAGNOSES

Endoscopy of upper gastrointestinal tract was performed twice with 2 months interval and a stenotic pyloric part was observed with a suspected submucosal lesion. It was sampled both times, however the pathology findings of the mucosal biopsies were unremarkable with no identifiable neoplastic structures. CT scan and MRI was performed and showed a thickened pyloric wall with a submucosal lesion 15 × 15 mm in diameter. Blood levels of tumor markers carcinoembrionic antigen and carbohydrate antigen 19-9 were within a normal range.

INTERVENTIONS

Pyloric stenosis progressed and the patient underwent a Billroth type I distal gastric resection with D2 lymphadenectomy. Pathologic examination revealed a well differentiated ductal adenocarcinoma arising in the heterotopic pancreatic tissue (Heinrich type III). The resection margins and lymph nodes were free of tumor. The patient received adjuvant chemotherapy with 6 courses of XELOX.

OUTCOMES

No disease recurrence is reported in 12 months follow-up.

LESSONS

Aberrant pancreatic ductal adenocarcinoma in the stomach is a rare finding, however this pathology should be included in the differential diagnosis of gastric submucosal lesion causing pyloric stenosis.

Clinical classification of symptomatic heterotopic pancreas of the stomach and duodenum: A case series and systematic literature review

BACKGROUND

Heterotopic pancreas (HP) is an aberrant anatomic malformation that occurs most commonly in the upper gastrointestinal tract. While the majority of heterotopic pancreatic lesions are asymptomatic, many manifest severe clinical symptoms which require surgical or endoscopic intervention. Understanding of the clinical manifestations and symptoms of HP is limited due to the lack of large volume studies in the literature. The purpose of this study is to review symptomatic cases at a single center and compare these to a systematic review of the literature in order to characterize common clinical manifestations and treatment of this disease.

AIM

To classify the common clinical manifestations of heterotopic pancreas.

METHODS

A retrospective review was conducted of pathologic samples containing heterotopic pancreas from 2000-2018. Review was limited to HP of the upper gastrointestinal tract due to the frequency of presentation in this location. Symptomatic patients were identified from review of the medical records and clinical symptoms were tabulated. These were compared to a systematic review of the literature utilizing PubMed and Embase searches for papers pertaining to heterotopic pancreas. Publications describing symptomatic presentation of HP were selected for review. Information including demographics, symptoms, presentation and treatment were compiled and analyzed.

RESULTS

Twenty-nine patient were identified with HP at a single center, with six of these identified has having clinical symptoms. Clinical manifestations included, gastrointestinal bleeding, gastric ulceration with/without perforation, pancreatitis, and gastric outlet obstruction. Systemic review of the literature yielded 232 publications detailing symptomatic cases with only 20 studies describing ten or more patients. Single and multi-patient studies were combined to form a cohort of 934 symptomatic patients. The majority of patients presented with abdominal pain (67%) combined with one of the following clinical categories: (1) Dyspepsia, (n = 445, 48%); (2) Pancreatitis (n = 260, 28%); (3) Gastrointestinal bleeding (n = 80, 9%); and (4) Gastric outlet obstruction (n = 80, 9%). The majority of cases (n = 832, 90%) underwent surgical or endoscopic resection with 85% reporting resolution or improvement in their symptoms.

CONCLUSION

Heterotopic pancreas can cause significant clinical symptoms in the upper gastrointestinal tract. Better understanding and classification of this disease may result in more accurate identification and treatment of this malformation.

Congenital anomalies of the gastrointestinal tract: the liver, extrahepatic biliary tree and pancreas

Congenital anomalies of the liver, biliary tree and pancreas are rare birth defects, some of which are characterized by a marked variation in geographical incidence. Morphogenesis of the hepatobiliary and pancreatic structures initiates from two tubular endodermal evaginations of the most distal portion of the foregut. The pancreas develops from a larger dorsal and a smaller ventral outpouching; emergence of the two buds will eventually lead to the fusion of the duct system. A small part of the remaining ventral diverticulum divides into a "pars cystica" and "pars hepatica", giving rise to the cystic duct and gallbladder and the liver lobes, respectively. Disruption or malfunctioning of the complex mechanisms leading to the development of liver, gallbladder, biliary tree and pancreas can result in numerous, albeit fortunately relatively rare, congenital anomalies in these organs. The type and severity of anomalies often depend on the exact moment in which disruption or alteration of the embryological mechanisms takes place. Many theories have been brought forward to explain their embryological basis; however, no agreement has yet been reached for most of them. While in some cases pathological evaluation might be more centered on macroscopic evaluation, in other instances small biopsies will be the keystone to understanding organ function and treatment results in the context of congenital anomalies. Thus, knowledge of the existence and histopathological characteristics of some of the more common conditions is mandatory for every pathologist working in the field of gastrointestinal pathology.

Primary pancreatic cancer of the jejunum: a case report and brief review of literature

The variable clinical presentation of heterotopic pancreatic (HP) tissue and its malignant transformation makes the diagnosis very challenging. These lesions are very rare, usually not suspected upon initial presentation and for the most part, are diagnosed incidentally on review of pathology following surgical resection. In this study, we are reporting an adenocarcinoma arising from jejunal heterotopic pancreatic tissue in a 59-year-old female and a brief review of previously reported cases.

Asymptomatic gastric adenomyoma and heterotopic pancreas in a patient with pancreatic cancer: A case report and review of the literature

BACKGROUND

Gastric adenomyoma (GA) is a rare submucosal benign neoplasm that occurs mostly in the gastric antrum and is often misdiagnosed. No standard treatment has been established for this disease in cases of malignancy.

CASE SUMMARY

A 75-year-old woman with a 10-year history of hypertension was admitted to the Emergency Department of our hospital complaining of paroxysmal exacerbation of acute abdominal pain for 1 d with no apparent cause. Enhanced computed tomography and magnetic resonance imaging indicated a mass in the caudal pancreas, cholecystitis, and cholecystic polypus. Gastrointestinal endoscopy showed a mass arising from the gastric antrum. Due to the imaging findings, pancreatic cancer (PC), gastric lesion, cholecystitis, and cholecystic polypus were our primary consideration. Radical pancreatectomy, splenectomy, and cholecystectomy were performed successfully, and the gastric tumor was locally resected. Postoperative paraffin specimens confirmed the diagnosis of caudal PC, GA, and heterotopic pancreas (HP). Unfortunately, the patient died 13 mo later due to PC metastases to the liver, lung, and adrenal glands.

CONCLUSION

GA is a rare benign disease, especially when occurring with HP. It may stem from the same origin as HP. This is the first case report to date of a patient suffering from the simultaneous occurrence of GA, HP, and PC. GA is a lesion that can mimic other benign or malignant gastrointestinal diseases; thus, a definitive diagnosis depends on postoperative pathological biopsy. Although GA and HP are both benign lesions, they should be resected because there is a chance of malignancy. Additional research should be conducted to better understand these submucosal lesions.

Pancreatic-type Mixed Acinar-neuroendocrine Carcinoma of the Stomach: A Case Report and Literature Review

BACKGROUND

Pancreatic-type mixed acinar-neuroendocrine carcinoma (PMANEC) in the stomach is very rare. We report a case of PMANEC that was initially misdiagnosed as a gastric neuroendocrine tumor.

CASE REPORT

A 63-year-old female was found to have a gastric mass by histology and immunohistochemistry. The tumor had a heterogenous histology, with areas resembling pancreatic acinar cell carcinoma and other areas exhibiting neuroendocrine features. Only the neuroendocrine component was present in the initial biopsy, resulting in the erroneous diagnosis of gastric neuroendocrine tumor. Evaluation of the final resected tumor revealed cells expressing pancreatic exocrine markers, including trypsin and chymotrypsin and BCL10 immune signaling adaptor. Large areas of the tumor (>30%) were also positive for chromogranin A and synaptophysin. The final diagnosis was PMANEC.

CONCLUSION

This type of gastric cancer is rare and may cause diagnostic difficulty, especially if only the neuroendocrine component of the tumor is sampled in a biopsy.

Gastric Adenocarcinoma Arising from Heterotopic Pancreas Presenting as Gastric Outlet Obstruction 10 Years after the First Diagnosis

Gastric heterotopic pancreas is a relatively uncommon incidental finding. On the other hand, the presentation of gastric adenocarcinoma arising from a heterotopic pancreas is rare. This paper reports a case of gastric adenocarcinoma arising from a heterotopic pancreas that presented as a gastric outlet obstruction 10 years after the initial diagnosis of a suspicious submucosal tumor. Endoscopy revealed a pyloric stricture with prepyloric wall thickening and a complete gastric outlet obstruction. Abdominal and pelvic computed tomography exposed a severely distended gastric lumen at the antrum with heterogeneously enhancing circumferential wall thickening in the prepyloric antrum and pylorus. Because conservative treatment was ineffective and a malignancy could not be excluded, laparoscopic subtotal gastrectomy with a gastrojejunostomy was performed for histological confirmation and treatment. The histopathology diagnosis was advanced gastric carcinoma arising from heterotopic pancreatic tissue.

Jejunal Intussusception Due to Heterotopic Pancreas: A Case Report

Intussusception in adults is rare. Even more unusual is jejunal intussusception secondary to a heterotopic pancreas. The presence of pancreatic tissue in an ectopic location and lacking contiguity with the main pancreatic gland is defined as pancreatic heterotopia. It is very rarely symptomatic and usually diagnosed incidentally during surgical intervention for other conditions. We report the case of a 78-year-old lady who presented with a history of constipation, abdominal pain, and vomiting. A CT scan revealed features of a proximal jejunojejunal intussusception secondary to a small soft tissue density lead point. After laparotomy and segmental jejunal resection, histopathology confirmed the diagnosis of ectopic pancreatic tissue as the lead point. Although uncommon, heterotopic pancreatic tissue should be included in the differential diagnosis for proximal small bowel intussusception.

Ectopic pancreas appearing as a giant gastric cyst mimicking gastric lymphangioma: a case report and a brief review

Background

Ectopic pancreas (EP) is defined as pancreatic tissue that lacks anatomical or vascular communication with the normal body of the pancreas. Despite improvements in diagnostic endoscopy and imaging studies, differentiating ectopic pancreatic tissue from gastric submucosal diseases remains a challenge.

Case presentation

Here, we present a case of a 44-year-old woman with severe epigastric pain. Initially, gastric lymphangioma was highly suspected due to a well-demarcated protruding mass with a large size that occurred in the submucosal layer of the gastric antrum and appeared as a cystic lesion. The final correct diagnosis of gastric EP was made during surgery.

Conclusion

Gastric EP with serous oligocystic adenoma appearing as a giant gastric cyst is extremely rare. The difficulty of making an accurate diagnosis and differential diagnosis is highlighted, which may provide additional clinical experience for the diagnosis of EP with serous oligocystic adenoma in the stomach.

CT differentiation of gastric ectopic pancreas from gastric stromal tumor

Background

Gastric ectopic pancreas (GEPs) is a rare developmental anomaly which is difficult to differentiate it from submucosal tumor such as gastric stromal tumor (GST) by imaging methods. Since the treatments of the GEPs and GST are totally different, a correct diagnosis is essential. Therefore, we retrospectively investigated the CT features of them to help us deepen the understanding of GEPs and GST.

Methods

This study enrolled 17 GEPs and 119 GST, which were proven pathologically. We assessed clinical and CT features to identify significant differential features of GEPs from GST using univariate and multivariate analyses.

Results

In univariate analysis, among all clinicoradiologic features, features of age, symptom, tumor marker, location, contour, peritumoral infiltration or fat-line of peritumor, necrosis, calcification, CT attenuation value of unenhancement phase/arterial phase/portal venous phase (CTu/CTa/CTp), the CT attenuation value of arterial phase/portal venous phase minus that of unenhanced phase (DEAP/DEPP), long diameter (LD), short diameter (SD) were considered statistically significant for the differentiation of them. And the multivariate analysis revealed that location, peritumoral infiltration or fat-line of peritumor, necrosis and DEPP were independent factors affecting the identification of them. In addition, ROC analysis showed that the test efficiency of CTp was perfect (AUC = 0.900).

Conclusion

Location, the presence of peritumoral infiltration or fat-line of peritumor, necrosis and DEPP are useful CT differentiators of GEPs from GST. In addition, the test efficiency of CTp in differentiating them was perfect (AUC = 0.900).

Gastric heterotopic pancreas in children: A prospective endoscopic study

PURPOSE

To document the prevalence and variable appearance of gastric heterotopic pancreas (HP) in children undergoing upper gastrointestinal (GI) endoscopy.

METHODS

A prospective 4-year study of children undergoing flexible upper GI endoscopy in a single institution.

RESULTS

A total of 607 upper GI endoscopies were performed in 478 pediatric patients during the 4-year period. Eleven children (6 girls, 5 boys) aged 2.9 to 16.9 years had endoscopic features typical of gastric HP. All but one lesion was located in the gastric antrum and most appeared as an umbilicated submucosal nodule measuring 1-2 cm in diameter. Five of 13 children with repaired esophageal atresia (EA) and two of nine children with trisomy 21 had gastric HP. The prevalence of endoscopically visualized gastric HP in children without a history of EA or trisomy 21 was 1.1%.

CONCLUSIONS

Gastric HP is present in about 1% of pediatric upper GI endoscopies. It is significantly more common in patients with EA and may also be associated with trisomy 21. Gastric HP typically appears as a single 1-2 cm antral submucosal nodule, usually with a central pit. Recognition of this lesion is important to avoid misdiagnosis and inappropriate treatment.

LEVEL OF EVIDENCE

Level II (diagnostic).

Evaluation and management of a pancreatic rest noted during pre-bariatric surgery screening endoscopy

INTRODUCTION

Pancreatic rest (PR) is an ectopic pancreatic lesion that is usually found incidentally on endoscopy or surgery. While most lesions do not have clinical significance, some patients are symptomatic and rarely, PR can predispose to malignancy. With the growing popularity of bariatric surgery, it has been unclear how to manage PR found on screening endoscopies, prior to bariatric surgery. Through review of the current literature, we propose an algorithm for clinicians to evaluate and manage PR found on screening endoscopies prior to bariatric surgery.

METHODS

We performed a literature search in PubMed pertaining to PR, clinical characteristics, risk of malignant transformation, endoscopic characteristics, histological descriptions, and resection techniques. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we found 33 published articles from 2001 to 2019, including case reports, case series, retrospective cohorts, and a review paper.

RESULTS

PR is commonly found incidentally in the gastric antrum. Larger lesions have a higher risk of being symptomatic or predisposing to malignant transformation. Endoscopic ultrasound (EUS) can assist in the diagnosis of PR and guide resection technique. Certain histological characteristics, such as Heinrich class, grading of neoplasia, and genetic alterations, can determine malignancy risk of PR. Resection technique, either endoscopically or surgically, should be based on lesion size, depth of wall invasion, and the endoscopists' level of skill in endoscopic resection.

CONCLUSIONS

Proper evaluation and treatment of PR should be considered because of the risk for symptoms and malignant transformation. Symptomatic lesions and those at risk for malignant transformation should be considered for resection. EUS can guide the diagnosis and type of resection, either endoscopically through EMR or ESD or surgically through sleeve gastrectomy or Roux-en-Y gastric bypass (RYGB).

Adenocarcinoma with intraductal papillary mucinous neoplasm arising in a duodenal heterotopic pancreas: a case report

A woman in her 70 s was diagnosed with a tumor in her duodenal wall during a routine visit for diabetes. She subsequently underwent subtotal stomach-preserving pancreatoduodenectomy. Histologically, the tumor was present mainly in the duodenal wall, and atypical cystic ducts were seen in the muscularis propria and subserosa. Invasive well-differentiated adenocarcinoma was seen in the duodenal submucosal and mucosal layers. Heterotopic pancreatic tissue was seen within the tumor, and atypical epithelium had proliferated and replaced the cystic ductal epithelium of the heterotopic pancreas. Therefore, adenocarcinoma with intraductal papillary mucinous neoplasm arising in duodenal heterotopic pancreas was the final histopathological diagnosis, which is considered rare.

A Rare Case of Well-Differentiated Neuroendocrine Tumor Arising From a Jejunal Pancreatic Heterotopia

Pancreatic heterotopia is a well-described entity occurring at multiple abdominal sites, most commonly the stomach and small intestine. They can develop similar disease processes as the pancreas ranging from acute pancreatitis, cyst formation, or neoplasms, most commonly ductal adenocarcinoma. Neuroendocrine tumors (NETs) arising in pancreatic heterotopias are exceedingly rare with only 3 prior published cases. In this article, we describe the first reported case of a NET arising in a jejunal pancreatic heterotopia in a 59-year-old woman presenting with abdominal pain and diarrhea. The submucosal tumor was composed of a well-differentiated NET (World Health Organization grade 1) directly intermixed with a heterotopic pancreas consisting of acinar cells, islet cells, and ducts. This case illustrates that NETs can occur in association with pancreatic heterotopias at any site. Also, the importance for pathologists to recognize that pancreatic heterotopias can give rise to a variety of neoplasms and is not limited to ductal adenocarcinoma.

Heterotopic pancreas adenocarcinoma in the stomach: A case report and literature review

BACKGROUND

Heterotopic pancreas is a common lesion found in the gastrointestinal tract and is usually considered a benign disease. Reports of malignant change of heterotopic pancreas are scarce.

CASE SUMMARY

A 44-year-old Chinese female underwent a gastroscopy to assess abdominal distension that had persisted for 2 months. A protruding lesion in the gastric antrum was revealed but no malignant tissue was found in the biopsy specimen. The patient's symptom persisted and progressed to repeated vomiting. Endoscopy after 4 months revealed obstruction of the gastric outlet caused by the protruding lesion. A distal gastrectomy was performed. Histopathological examination of the surgical specimen showed the malignant transformation of aberrant pancreas in the stomach. Chemotherapy consisting of folinic acid, fluorouracil, and oxaliplatin was administered for three cycles, and was changed to gemcitabine monotherapy because of adverse effects and increased serum tumor marker levels. The patient remained asymptomatic during a 12-month follow-up.

CONCLUSION

Pancreatic heterotopy should be considered as source of a potentially malignant lesion, and early treatment or close monitoring for aberrant pancreas is recommended.

Rare gastric outlet obstruction owing to ectopic pancreas: a case report and literature review

The ectopic pancreas is often observed in the gastrointestinal tract, and is typically asymptomatic. A 28-year-old woman was referred to our hospital following repeated vomiting after every meal. Following gastroscopy, contrast-enhanced computed tomography (CE-CT), and endoscopic ultrasonography (EUS), she was diagnosed with gastric outlet obstruction, also known as pyloric obstruction, caused by a giant submucosal cystic tumor. The condition was successfully treated with EUS-guided cystic drainage, and she was diagnosed with a cystic tumor originating from the ectopic pancreas. The tumor shrank following EUS-guided cystic drainage, and her obstructive symptoms resolved. In cases with overgrowth of the ectopic pancreas, the differential diagnosis of malignancy is important but challenging. Herein, we report a unique final pathology of this rare case and discuss the findings with a literature review.

Ectopic pancreatitis in the antral stomach causing gastric outlet obstruction: a case of successful resection

Ectopic pancreas is a congenital developmental anomaly that may be caused by embryologic errors. The pathogenetic details of ectopic pancreas remain unclear, but it has gradually been determined to originate at the gene level. DNA errors during embryological development cause ectopic pancreas. Ectopic pancreas is generally asymptomatic and harmless throughout the patient's entire life; in very rare cases, however, it can be symptomatic and harmful, causing pain, fever, bleeding, and other adverse effects. We herein report an unusual case involving a 52-year-old Japanese woman who presented with nausea and vomiting due to inflammation of an ectopic pancreas in the gastric antrum. Ectopic pancreatitis caused severe pyloric stenosis, and she was unable to ingest food or water even after admission to the internal medicine ward. Ectopic pancreatitis is a very rare clinical condition, but clinicians should be cautious of this uncommon disease in patients who develop gastric outlet obstruction without cancer or ulcers. The present case report is clinically significant because surgical treatment (distal partial gastrectomy) relieved the patient's serious distress rapidly and successfully after unsuccessful conservative treatments for acute ectopic pancreatitis. Antrectomy (distal partial gastrectomy) might be useful for ectopic pancreas, especially in case of gastric outlet obstruction due to the ectopic pancreatitis.

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.

The malignancy among gastric submucosal tumor

The origin and characteristics of most submucosal tumors (SMTs) cannot easily be confirmed by gastrointestinal endoscopy or other radiological examinations. Excluding GISTs, for those other gastric SMTs, most of which are deemed benign, the necessity and timing of intervention has been ignored. Thus, the malignancy of gastric SMTs still remains unknown. In order to summarize the malignancy of these gastric SMTs, we reviewed literatures and analyzed cases of gastric SMTs including heterotopic pancreas, leiomyoma, schwannoma, glomus tumor, hemangioendothelioma, granular cell tumor (GCT), lipoma, hemangiopericytoma, lymphangioma and neurofibroma. In these literatures, there are cases of malignancy among heterotopic pancreas, leiomyoma, schwannoma, glomus tumor, hemangioendothelioma and GCT. As a result, it suggests that although most of gastric SMTs are considered benign, there are still possibilities of malignancy, which requires our attention, even active intervention and long-term follow-up.

Endoscopic management of gastric outlet obstruction disease

Gastric outlet obstruction (GOO) is a clinical syndrome characterized by a variety of symptoms. It may be caused by motor disorders and by benign or malignant mechanical disease. Endoscopic management of benign disease is mainly based on balloon dilation, augmented by the use of covered self-expanding metal stents (SEMS) in refractory disease. Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) is increasingly used as an alternative method, although more studies with longer follow up are needed before it can be considered as a recommended therapy. Surgery remains the last resort. Endoscopic management of malignant GOO is based on SEMS placement as an alternative to palliative surgery, because it is a cost-effective method. The use of a covered or uncovered stent depends on patient-related variables, which include the stricture site, concomitant involvement of the bile duct, the patient's prognosis, probably the tumor type, and the use of chemotherapy. EUS-GE is a promising technique but needs more studies with longer follow up before any firm conclusions can be drawn.

Endoscopic management of gastric outlet obstruction disease

Gastric outlet obstruction (GOO) is a clinical syndrome characterized by a variety of symptoms. It may be caused by motor disorders and by benign or malignant mechanical disease. Endoscopic management of benign disease is mainly based on balloon dilation, augmented by the use of covered self-expanding metal stents (SEMS) in refractory disease. Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) is increasingly used as an alternative method, although more studies with longer follow up are needed before it can be considered as a recommended therapy. Surgery remains the last resort. Endoscopic management of malignant GOO is based on SEMS placement as an alternative to palliative surgery, because it is a cost-effective method. The use of a covered or uncovered stent depends on patient-related variables, which include the stricture site, concomitant involvement of the bile duct, the patient’s prognosis, probably the tumor type, and the use of chemotherapy. EUS-GE is a promising technique but needs more studies with longer follow up before any firm conclusions can be drawn.

Gastric Heterotopic Pancreas Presenting as Abdominal Pain with Acute and Chronic Pancreatitis in the Resected Specimen

Heterotopic pancreas, also known as ectopic pancreas, is pancreatic tissue located outside the pancreatic parenchyma without vascular or ductal communication with the gland. Ectopic pancreas is rarely symptomatic, typically detected incidentally at surgery or autopsy. Eighty-five to 90% are in the upper GI tract, especially the gastric antrum. We report a 54-year-old man with symptomatic gastric heterotopic pancreas presenting as recurrent, initially undiagnosed, abdominal pain. Surgery revealed heterotopic pancreas including excretory ducts, acini, and islet cells. Evidence of acute pancreatitis was present, marked by inflammation and abscess formation. Chronic pancreatitis was diagnosed by fibrosis and dilated ducts containing proteinaceous material. Submucosal location with normal overlying mucosa on endoscopy increases risks of delayed or missed diagnosis. Complications include GI bleeding, acute or chronic pancreatitis, pancreatic necrosis, pseudocyst, gastric outlet obstruction, perforation, and, rarely, pancreatic carcinoma. This rare disorder mimics more common diseases. Low suspicion, nondiagnostic imaging or endoscopy contribute to frequent diagnostic delay.

Malignant Transformation of Ectopic Pancreas

Malignant transformation of ectopic pancreas tissue is a diagnostic challenge as clinical symptoms and radiographic features of these tumors are non-specific. Given the rarity of these lesions, it is usually neither suspected nor included in the diagnostic workup of different tumors. We conducted a comprehensive literature review regarding malignancy arising from ectopic pancreas for a better understanding of its frequency, clinicopathological features, and prognosis. A literature search was performed in three major databases: PubMed, Cochrane, and Web of Science. Fifty-four well-documented cases of malignant ectopic pancreas were identified in the published literature. Our analysis provided the following observations: (1) there was a slight predominance of males over females; (2) most patients with malignant transformation of ectopic pancreas were middle-aged; (3) most commonly, the tumor was located in the stomach; (4) most tumors were adenocarcinomas; (5) most frequently, the malignancy arose within a type I heterotopia according to Heinrich classification; (6) macroscopically, a subepithelial-like appearance was most frequently observed; and (7) improved prognosis for ectopic pancreatic malignancies in comparison with reported survival data for orthotopic pancreatic cancer. Even if the majority of cases of ectopic pancreas are incidental findings and malignant transformation is a rare event, pancreatic heterotopy should be considered as a source of potentially malignant lesions.

Malformations, choristomas, and hamartomas of the gastrointestinal tract and pancreas

Congenital and hamartomatous lesions of the gastrointestinal tract cause diagnostic challenges for surgical pathologists. Many of these are merely histologic curiosities, whereas others have substantial clinical implications because they herald cancer syndromes or associated anomalies. Although a comprehensive discussion of all developmental abnormalities that can occur in the gastrointestinal tract is beyond the scope of a single manuscript, some entities are more likely to be encountered by surgical pathologists, have important clinical consequences, or pose diagnostic difficulties. The purpose of this review is to discuss the more common malformations and choristomas, as well as hamartomatous lesions that may be clinically important due to their risk for cancer development, frequent associations with heritable cancer syndromes and other anomalies, or potential to simulate other entities.

Pancreatic intraepithelial neoplasia in heterotopic pancreas: incidentally diagnosed on endoscopic mucosal resection of a duodenal polyp

Heterotopic pancreas is the presence of pancreatic tissue outside its normal location. It can develop similar pathological conditions that develop in the normal pancreas, including adenocarcinoma and its precursor lesions. Due to the rarity of the condition, the diagnosis can be challenging, and treatment is not well established. ​We present a 47-year-old female patient referred for endoscopic resection of a 2 cm polyp in the second part of her duodenum. Complete endoscopic mucosal resection (EMR) was performed, with pathology revealing low-grade pancreatic intraepithelial neoplasia (PanIN) in heterotopic pancreatic tissue. To the best of our knowledge, this is the first case of heterotopic pancreas with low-grade PanIN in the duodenum to be incidentally diagnosed and treated with EMR.

Gastric Heterotopic Pancreas: Computed Tomography With Clinicopathologic Correlation

Asymptomatic heterotopic pancreas (HP) is benign and can be monitored long term without further intervention. Heterotopic pancreas is sometimes surgically resected because it can be difficult to distinguish HP from neoplastic submucosal masses such as gastrointestinal stromal tumors. Although it is not very common, HP should be considered in the differential diagnosis when diagnosing extramucosal gastric masses to avoid unnecessary intervention. We review gastric HP with pathologic correlation to help with diagnosing HP on computed tomography.

Heterotopic Pancreas of the Gastrointestinal Tract and Associated Precursor and Cancerous Lesions: Systematic Pathologic Studies of 165 Cases

Heterotopic pancreas (HP) can be detected by accompanying symptoms or incidentally during gastrointestinal (GI) tract tumor resection. We compared clinicopathologic features among 165 resected HPs (57 gastric [35%], 56 duodenal [34%], 30 omental [18%], and 22 jejunal [13%]). Symptomatic HPs (79/135 GI tract wall HPs, 59%) were larger (P=0.05), more common in younger patients and in a gastric location (both P<0.001), and more frequently associated with lymphoid cuffs (P=0.03) than incidentally found HPs. Gastric/jejunal HPs were more frequently symptomatic (P<0.001), deeply located (P=0.03), and associated with lymphoid cuffs (P=0.008) and pancreatic intraepithelial neoplasia/intraductal papillary mucinous neoplasms (PanIN/IPMN; P=0.001) than duodenal HPs. HP was frequently associated with acinar-ductal metaplasias (117/135 GI tract wall HPs, 87%) and PanINs/IPMNs (68/135, 50%); those with PanINs/IPMNs were larger (P<0.001), more frequently located in stomach (P=0.001), had deeper wall involvement (P=0.03), and more often showed infiltrative growth (P<0.001) and lymphoid cuffs (P=0.02). Four HPs containing PanINs abutted adenocarcinomas, all expressing wild-type KRAS and intact SMAD4/DPC4 expression. Thus, symptomatic HP is associated with younger age, larger size, gastric location, and lymphoid cuffs. HPs containing PanINs/IPMNs (usually low grade) are larger and more common in stomach, have deeper wall location, and show infiltrative growth and lymphoid cuffs. Adenocarcinomas are rarely observed adjacent to HPs with PanINs/IPMNs. KRAS mutational and SMAD4/DPC4 immunohistochemical studies can discriminate between adenocarcinoma derived from HP and concurrent adenocarcinoma with HP.

Clinical impact of duodenal pancreatic heterotopia - Is there a need for surgical treatment?

BACKGROUND

Pancreatic heterotopia (PH) is defined as ectopic pancreatic tissue outside the normal pancreas and its vasculature and duct system. Most frequently, PH is detected incidentally by histopathological examination. The aim of the present study was to analyze a large single-center series of duodenal PH with respect to the clinical presentation.

METHODS

A prospective pancreatic database was retrospectively analyzed for cases of PH of the duodenum. All pancreatic and duodenal resections performed between January 2000 and October 2015 were included and screened for histopathologically proven duodenal PH. PH was classified according to Heinrich's classification (Type I acini, ducts, and islet cells; Type II acini and ducts; Type III only ducts).

RESULTS

A total of 1274 pancreatic and duodenal resections were performed within the study period, and 67 cases of PH (5.3%) were identified. The respective patients were predominantly male (72%) and either underwent pancreatoduodenectomy (n = 60); a limited pancreas resection with partial duodenal resection (n = 4); distal pancreatectomy with partial duodenal resection (n = 1); total pancreatectomy (n = 1); or enucleation (n = 1). Whereas 65 patients (83.5%) were asymptomatic, 11 patients (18.4%) presented with symptoms related to PH (most frequently with abdominal pain [72%] and duodenal obstruction [55%]). Of those, seven patients (63.6%) had chronic pancreatitis in the heterotopic pancreas. The risk of malignant transformation into adenocarcinoma was 2.9%.

CONCLUSIONS

PH is found in approximately 5% of pancreatic or duodenal resections and is generally asymptomatic. Chronic pancreatitis is not uncommon in heterotopic pancreatic tissue, and even there is a risk of malignant transformation. PH should be considered for the differential diagnosis of duodenal lesions and surgery should be considered, especially in symptomatic cases.

Ectopic Pancreas Imitating Gastrointestinal Stromal Tumor (GIST) In The Stomach

Ectopic pancreas is a rare congenital disorder defined as pancreatic tissue lacking vascular or anatomic communication with the normal body of the pancreas. Most cases of ectopic pancreas are asymptomatic, but it may become clinically evident depending on the size, location and the pathological changes similar to those observed in case of the normal pancreas. It is often an incidental finding and can be located at different sites in the gastrointestinal tract. The most common locations are: the stomach, duodenum or the proximal part of small intestine. The risk of malignancy, bleeding and occlusion are the most serious complications. Despite the development in diagnostics, it still remains a challenge for the clinician to differentiate it from neoplasm. In this report, we described a case of 28-years old woman who presented recurrent epigastric pain. The upper gastrointestinal endoscopy revealed gastrointestinal stromal tumor on the border of the body and antrum of the back wall of great curvature of the stomach. The histopathological examination after surgery showed heterotopic pancreatic tissue. Ectopic pancreas should be considered in the differential diagnosis of gastric mass lesions.

Minimally Invasive Management of Ectopic Pancreas

BACKGROUND

The management of ectopic pancreas is not well defined. This study aims to determine the prevalence of symptomatic ectopic pancreas and identify those who may benefit from treatment, with a particular focus on robotically assisted surgical management.

METHODS

Our institutional pathology database was queried to identify a cohort of ectopic pancreas specimens. Additional clinical data regarding clinical symptomatology, diagnostic studies, and treatment were obtained through chart review.

RESULTS

Nineteen cases of ectopic pancreas were found incidentally during surgery for another condition or found incidentally in a pathologic specimen (65.5%). Eleven patients (37.9%) reported prior symptoms, notably abdominal pain and/or gastrointestinal bleeding. The most common locations for ectopic pancreas were the duodenum and small bowel (31% and 27.6%, respectively). Three out of 29 cases (10.3%) had no symptoms, but had evidence of preneoplastic changes on pathology, while one harbored pancreatic cancer. Over the years, treatment of ectopic pancreas has shifted from open to laparoscopic and more recently to robotic surgery.

CONCLUSIONS

Our experience is in line with existing evidence supporting surgical treatment of symptomatic or complicated ectopic pancreas. In the current era, minimally invasive and robotic surgery can be used safely and successfully for treatment of ectopic pancreas.

Ectopic pancreatic tissue in the stomach: Case report

Introduction: Ectopic pancreas is a rare developmental anomaly. It is a presence of pancreatic tissue without anatomic or vascular continuity with the normally developed pancreas. The most common heterotopic site is the stomach commonly involving antrum and prepyloric region on the greater curvature or posterior wall. Ectopic pancreas is diagnosed by endoscopic ultrasound, gastroscopy and biopsy, CT scan and MRI of the abdomen, a definitive diagnosis is verified by histopathological examination. Treatment is surgical. Case report: A 56-year-old woman presented with epigastric pain, nausea and fatigue. Esophagogastroduodenoscopy showed submucosal mass in the prepyloric region, biopsy was performed. Histopathological findings described normal gastric mucosa. Endoscopic ultrasonography and CT of the abdomen showed submucosal tumor, 18 mm in diameter, located in the prepyloric region. Surgical treatment was indicated. Gastrotomy with total extraction of tumor was performed. Histopathology findings showed ectopic pancreatic tissue in the submucosal and muscular layer of the stomach. Postoperatively patient fully recovered, and in the 2 year follow-up did not develop any symptoms related to gastrointestinal tract. Conclusion: Although presentation of ectopic pancreatic tissue in stomach is a very rare condition, it should be considered during gastroitestinal diagnostic in patients with nonspecific gastrointestinal symptomatology. In most of cases, for this patients, surgery is curative and definitive solution.

Heterotopic pancreatic pseudocyst radiologically mimicking gastrointestinal stromal tumor

Heterotopic pancreas is a relatively common variant of foregut embryologic dystopia that can be described as pancreatic tissue found outside the normal anatomic location, being independent from vascular supply of normal pancreas. Having all features of pancreatic tissue except for the major duct structures, this ectopic tissue may be clinically recognized when pathologic changes take place. Inflammation, hemorrhagic or obstructive states, and eventually malignancy-related problems may become a diagnostic challenge for clinician and finally lead to consequences of misdiagnosis. In this article we will discuss a case of heterotopic pancreatic tissue located in gastric cardia, which was diagnosed preoperatively as gastrointestinal stromal tumor.

Early Gastric Cancer Just above a Heterotopic Pancreas

We report the first case of early gastric cancer just above a heterotopic pancreas for which the differential diagnosis was carcinoma arising from heterotopic pancreas. Routine upper gastrointestinal endoscopy in an 83-year-old man with sigmoid colon cancer revealed a gastric cancer in the lesser curvature of the antrum. Endoscopic ultrasonography (EUS) for evaluating the depth of tumor invasion revealed a hypoechoic mass in the submucosal layer. The depth of tumor invasion was diagnosed as muscularis propria. Distal gastrectomy and sigmoidectomy were performed. Histologically, the resected specimen of the stomach unexpectedly revealed a heterotopic pancreas just below the gastric cancer. They were not linked, and the heterotopic pancreas had no dysplasia. The gastric cancer had slightly invaded the submucosa. The hypoechoic mass on EUS was not the invasive tumor but the heterotopic pancreas. The preoperative staging of the gastric cancer on EUS was confounded by the presence of the heterotopic pancreas just below the gastric cancer.

Hepatoid adenocarcinoma arising from heterotopic pancreas of the ileum: A case report

INTRODUCTION

Hepatoid adenocarcinoma (HAC) is a rare neoplasm with a striking morphologic similarity to hepatocellular carcinoma. The most common sites of HAC are the stomach, lung, and pancreas.

CASE REPORT

Here we report a rare case of HAC arising from the heterotopic pancreas (Heinrich type II) in the ileum with lymph node metastasis. A 56-year-old man was admitted to our hospital presenting with bloody stools under no obvious predisposing causes. The colonoscopy and the gastroscopy showed no pathological findings. A computed tomography scan showed an intussusception of ileum. Then partial resection of ileum was performed with end-to-end anastomosis and appendectomy. Histopathological examination showed a malignant transformation of heterotopic pancreas (Heinrich type II) in the ileum. We made the diagnosis of HAC based on clinical pathological features and immunochemical staining. The patient received chemotherapy and died 9 months later.

CONCLUSION

To our best knowledge, this is the first reported case of HAC originated from a heterotopic pancreas in the ileum. The clinical pathological features and immunochemical staining are important for correct diagnosis of HAC.

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.

Gastric fundal heterotopic pancreas mimicking a gastrointestinal stromal tumour (GIST): a case report and a brief review

BACKGROUND

Heterotopic pancreas is a rare congenital condition characterised by pancreatic tissue lacking vascular or anatomic communication with the normal pancreas. Most cases of ectopic pancreas are asymptomatic. The preoperative diagnosis of this condition is difficult.

CASE PRESENTATION

A 50-year-old woman presented with dyspeptic symptoms of 4 years duration. Contrast enhanced CT (computed tomography) scan of abdomen suggested a gastrointestinal stromal tumour in the fundus of the stomach. The patient underwent laparoscopy assisted resection and subsequent histology revealed ectopic pancreatic tissue.

CONCLUSION

Although heterotopic pancreas is a rare lesion diagnosed on histology, it should be considered in the differential diagnosis of gastric mass lesions and in patients presenting with vague upper gastrointestinal symptoms.

Mutational spectrum of intraepithelial neoplasia in pancreatic heterotopia

Heterotopic pancreatic parenchyma recapitulates the normal pancreas in extrapancreatic locations and, on rare occasions, can even give rise to pancreatic adenocarcinoma. The genetic signatures of pancreatic adenocarcinoma and its precursor lesions are well characterized. We explored the genetic alterations in precursor lesions (intraductal papillary mucinous neoplasms [IPMN], pancreatic intraepithelial neoplasia [PanIN]) in patients with pancreatic heterotopias but without concomitant pancreatic ductal adenocarcinomas. This allowed us to determine whether the stereotypical dysplasia--infiltrating carcinoma sequence also occurs in these extrapancreatic foci. Seven cases of heterotopic pancreas with ductal precursor lesions were identified. These included 2 IPMNs with focal high-grade dysplasia and 5 PanINs with low- to moderate-grade dysplasia (PanIN grades 1-2). Neoplastic epithelium was microdissected and genomic DNA was extracted. Sequencing of commonly mutated hotspots (KRAS, TP53, CDKN2A, SMAD4, BRAF, and GNAS) in pancreatic ductal adenocarcinoma and its precursor lesions was performed. Both IPMNs were found to have KRAS codon 12 mutations. The identification of KRAS mutations suggests a genetic pathway shared with IPMN of the pancreas. No mutations were identified in our heterotopic PanINs. One of the possible mechanisms for the development of dysplasia in these lesions is field effect. At the time of these resections, there was no clinical or pathologic evidence of a prior or concomitant pancreatic lesion. However, a clinically undetectable lesion is theoretically possible. Therefore, although a field effect cannot be excluded, there was no evidence for it in this study.

Diagnosis of ectopic pancreas by endoscopic ultrasound with fine-needle aspiration

AIM: To study the clinical, endoscopic, sonographic, and cytologic features of ectopic pancreas (EP).

METHODS: This was a retrospective study performed at an academic referral center including two hospitals. Institutional review board approval was obtained. Patients referred to the University Hospital or Denver Health Medical Center Gastrointestinal Endoscopy Lab for gastroduodenal subepithelial lesions (SEL) with a final diagnosis of EP between January 2009 and December 2013 were identified. Patients in this group were selected for the study if they underwent endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) or deep biopsy. A review of the medical record was performed specifically to review the following information: presenting symptoms, endoscopic and EUS findings, computed tomography or magnetic resonance imaging findings, pathology results, procedure-related adverse events, and subsequent treatments after EUS-FNA. EUS with FNA or deep submucosal biopsy was performed in all patients on an outpatient basais by one of two physicians (Attwell A, Fukami N). Review of all subsequent clinic notes and operative reports was performed in order to determine follow-up and final diagnoses.

RESULTS: Between July 2009 and December 2013, 10 patients [3 males, 7 females, median age 52 (26-64) years] underwent EUS for a gastroduodenal SEL and were diagnosed with EP. One patient was symptomatic. Six (60%) lesions were in the antrum, 3 (30%) in the body, and 1 (10%) in the duodenum. A mucosal dimple was noted in 6 (60%). Mean lesion size was 17 (8-25) mm. Gastrointestinal wall involvement: muscularis mucosae, 10%; submucosa, 70%; muscularis propria, 60%; and serosa, 10%. Nine (90%) lesions were hypoechoic and 5 (50%) were homogenous. A duct was seen in 5 (50%). FNA was attempted in 9 (90%) and successful in 8 (80%) patients after 4 (2-6) passes. Cytology showed acini or ducts in 7 of 8 (88%). Superficial biopsies in 7 patients (70%) showed normal gastric mucosa. Deep endoscopic biopsies were taken in 2 patients and diagnostic in one. One patient (10%) developed pancreatitis after EUS-FNA. Two patients (20%) underwent surgery to relieve symptoms or confirm the diagnosis. The main limitation of the study was the fact that it was retrospective and performed at a single medical center.

CONCLUSION: EUS features of EP include antral location, mucosal dimple, location in layers 3-4, and lesional duct, and FNA or biopsy is accurate and effective.

Pancreatic intraepithelial neoplasia arising from an ectopic pancreas in the small bowel

BACKGROUND

Ectopic pancreatic tissue is relatively uncommon, and is characterized as pancreatic tissue with no contact with the normal pancreas, and with its own ductal system and blood supply. It is usually asymptomatic, and can be incidentally diagnosed by conventional imaging studies.

METHOD

A 69-year-old woman with a prior history of bilateral breast carcinoma presented with ectopic pancreatic intraepithelial neoplasia (PanIN) that was identified incidentally in the small bowel during an oncological resection of a synchronous primary pancreatic adenocarcinoma, and renal cell carcinoma.

RESULTS

The patient underwent subtotal pancreatectomy with splenectomy, regional lymphadenectomy, radical left nephrectomy, and small bowel resection with primary anastomosis of ectopic PanIN-2. She had an uneventful hospitalization and was discharged home on postoperative day 7.

CONCLUSIONS

The occurrence of ectopic PanIN is extremely unusual with only few cases previously reported in the literature. The need for negative margins after surgical resection of ectopic PanIN lesions remains controversial.

Heterotopic pancreas: a rare cause of ileo-ileal intussusception

BACKGROUND

Heterotopic pancreas is a rare developmental anomaly defined as pancreatic tissue found on ectopic sites without contiguity with the main pancreas. An isolated heterotopic pancreas as a cause of bowel intussusception is extremely rare.

CASE REPORT

A case of 47-year old male with multiple episodes of melena, constipation and abdominal pain for one year duration is presented. CT eneterography revealed a large circumferential lesion involving the terminal ileum that acted as a leading point to an ileo-ileal intussusception. The resection of the lesion and related bowel segment was carried out. The histopathological examination confirmed the excised lesion as a heterotopic pancreatic tissue.

CONCLUSIONS

Though a rare entity, heterotopic pancreas should be considered in the differential diagnosis of bowel intussusception.

Acute ectopic pancreatitis occurring after endoscopic biopsy in a gastric ectopic pancreas

Ectopic pancreas is a congenital anomaly and the most common type of ectopic tissue in the gastrointestinal tract. Most patients with an ectopic pancreas are asymptomatic and rarely have complications. Ectopic pancreatitis after an endoscopic biopsy has not been reported. We report a patient who developed acute ectopic pancreatitis in the stomach after an endoscopic biopsy. A 71-year-old male patient presented with a subepithelial tumor (SET) in the stomach and had no symptoms. Endoscopic ultrasonography demonstrated a 30-mm hypoechoic mural mass, lobulated margins, and anechoic duct-like lesions. To obtain proper tissue specimen, endoscopic biopsy was performed through the opening on the surface of the mass. The pathologic results confirmed an ectopic pancreas. One day after the endoscopic biopsy, he developed persistent epigastric pain. His serum amylase and lipase elevated. Computed tomography of the abdomen showed swelling of the SET and diffuse edema of the gastric wall. His condition was diagnosed as acute ectopic pancreatitis occurring after endoscopic biopsy.

Induction of acute ectopic pancreatitis by endoscopic ultrasound with fine-needle aspiration

Ectopic pancreas rarely causes symptoms or complications. We analyzed 2 atypical cases of ectopic pancreas associated with acute ectopic pancreatitis, 1 of which was induced by endoscopic ultrasound with fine-needle aspiration (EUS-FNA). The patients were seen at a tertiary medical center where they had undergone computed tomography, esophagogastroduodenoscopy, and EUS-FNA analyses. They initially received conservative medical treatment and were later treated by surgery. Both patients were diagnosed with ectopic pancreas of the stomach on the basis of computed tomography, esophagogastroduodenoscopy, or EUS-FNA. Surgical resection cured both patients and confirmed the diagnosis of ectopic pancreas. Acute ectopic pancreatitis is an unusual complication of ectopic pancreas that can be induced by EUS-FNA and diagnosed and cured with surgery.

Ectopic tissue consisting of a mixture of glandular gastric, intestinal, and exocrine pancreatic tissue in the forestomach of a rat

The development of ectopic gastric, intestinal, or pancreatic tissue in the gastrointestinal tract is extremely rare in rats, although it is fairly common in humans. In this report, we describe an unusual case in which a mixture of different types of ectopic tissue was found in the forestomach of a rat. A solitary white nodular/polypoid structure, which measured 5 mm in size, was detected on the luminal surface of the greater curvature of the forestomach in an 8-week-old female Crl:CD(SD) rat. A histological examination revealed that the lesion contained ectopic glandular gastric tissue, including gastric surface mucous cells, parietal cells, and pyloric gland cells, which was confirmed by immunohistochemistry. Moreover, the lesion also contained villin-positive columnar intestinal absorptive cells and chymotrypsin-positive pancreatic exocrine tissue. To the best of our knowledge, this is the first study to detect a mixture of ectopic glandular gastric, intestinal, and exocrine pancreatic tissue in a rat.

Congenital variants and anomalies of the pancreas and pancreatic duct: imaging by magnetic resonance cholangiopancreaticography and multidetector computed tomography

Though congenital anomalies of the pancreas and pancreatic duct are relatively uncommon and they are often discovered as an incidental finding in asymptomatic patients, some of these anomalies may lead to various clinical symptoms such as recurrent abdominal pain, nausea and vomiting. Recognition of these anomalies is important because these anomalies may be a surgically correctable cause of recurrent pancreatitis or the cause of gastric outlet obstruction. An awareness of these anomalies may help in surgical planning and prevent inadvertent ductal injury. The purpose of this article is to review normal pancreatic embryology, the appearance of ductal anatomic variants and developmental anomalies of the pancreas, with emphasis on magnetic resonance cholangiopancreaticography and multidetector computed tomography.

Intraductal papillary mucinous neoplasm originating from a jejunal heterotopic pancreas: report of a case

We report a rare case of an intraductal papillary mucinous neoplasm (IPMN) originating from a jejunal heterotopic pancreas, found incidentally during surgery. A 75-year-old woman was referred to our department for surgical treatment of an abdominal aortic aneurysm (AAA) and a concurrent oropharyngeal tumor. During surgery to correct the AAA, we found a jejunal tumor incidentally and performed partial resection of the jejunum. Microscopically, the jejunal tumor showed dilated ducts containing intraluminal papillae lined with mucinous epithelium with low-grade cytological and architectural atypia within the pancreatic tissue. Immunohistochemical staining revealed MUC1 (-), MUC2 (-), MUC5AC (+), and MUC6 (-) proteins. To the best of our knowledge, only six cases of IPMN originating from a heterotopic pancreas have been reported in English, and this is the first report of an IPMN originating from a jejunal heterotopic pancreas.

The prevalence of pancreatic acinar differentiation in gastric adenocarcinoma: report of a case and immunohistochemical study of 111 additional cases

Although pancreatic acinar metaplasia in the gastric mucosa is well recognized in chronic gastritis, gastric carcinoma with acinar differentiation is very rare. We encountered a case of gastric adenocarcinoma with prominent histologic and immunohistochemical features of pancreatic acinar differentiation in the absence of identifiable heterotopic pancreatic tissue. Distinct glandular and diffuse patterns of adenocarcinoma were also present, and there was focal mucin production. The tumor strongly expressed pancreatic exocrine enzymes trypsin and chymotrypsin, and focal neuroendocrine staining was also present. To investigate the prevalence of acinar differentiation in histologically typical gastric cancers, we performed immunohistochemical staining for trypsin and chymotrypsin on a tissue microarray containing 111 conventional gastric adenocarcinomas (60 intestinal, 28 mixed, 22 diffuse type, and 1 undifferentiated). No obvious morphologic evidence of acinar differentiation was identified in any of the 111 cases. Although some cases showed equivocal staining for at least 1 pancreatic exocrine enzyme on the initial tissue microarray sections, repeat immunohistochemical staining on representative whole-tissue sections failed to reproduce positive staining. Thus, acinar differentiation is rare in gastric adenocarcinomas, other than in histologically unusual cases such as the one we report, and in others from the literature, which are reviewed.