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

Ectopic pancreas induced ileocecal intussusception: A rare case report

Introduction and importance: Ectopic pancreas is not uncommon, but ileocecal intussusception caused by ectopic pancreas is extremely rare. Thus far, only approximately 10 cases have been reported. Case presentation: Herein, we report a 47-year-old male who presented with abdominal distension and discomfort without apparent cause, accompanied by nausea but no vomiting or other symptoms. The patient's vital signs were stable, and examination revealed increased bowel sounds, tympanic percussion of the abdomen, and tenderness in the lower right abdomen. After laparoscopic exploration, an irreducible intestinal obstruction was found, which subsequently required open surgery. Pathological examination of the resected portion revealed that the patient's ileocecal intussusception was caused by ectopic pancreas. Clinical discussion: Prior to receiving the pathological report, we were not aware that the patient's abdominal pain may have been attributed to ileocecal intussusception induced by ectopic pancreas. This posed challenges in diagnosis and treatment, underscoring the importance of raising awareness among our colleagues through this case report. Conclusion: Our findings emphasize the need to consider the possibility of abdominal pain caused by ileocecal intussusception induced by ectopic pancreas during the investigation of abdominal pain.

Heterotopic pancreas in Meckel's diverticulum causing perforation in an infant: a case report

Perforation of Meckel's diverticulum caused by heterotopic pancreas is a rare condition. Despite recent improvements in imaging studies, Meckel"'s diverticulitis and heterotopic pancreas are difficult to diagnose preoperatively and are often diagnosed during autopsy or laparotomy. Symptomatic patients are typically >1 year, and cases of infants displaying symptoms are rarely reported. We report a rare case of heterotopic pancreas in Meckel's diverticulum causing perforation in an infant. In cases of infants presenting with unexplained acute abdominal pain, there should be a high index of suspicion for congenital gastrointestinal malformations. Prompt action in the form of exploratory laparotomy or laparoscopy is crucial to prevent the escalation of complications and to definitively confirm the diagnosis.

Esophageal Atresia and Gastric Ectopic Pancreas: Is There a Real Association?

OBJECTIVE

 Heterotopic pancreas (HP) is a condition in which there is well-differentiated pancreatic tissue that lacks any anatomic or vascular contact with the pancreatic gland. It normally arises from the stomach but can be found in other locations. Although it is usually asymptomatic, obstructive symptoms, bleeding, or malignant degeneration can occur. The incidence is very low, but it is significantly more common in patients with esophageal atresia (EA). The aim of this study is to evaluate the incidence of HP in patients with and without EA and to compare the results in both groups.

MATERIAL AND METHODS

 We conducted a 2-year prospective study in pediatric patients who benefited from an upper gastrointestinal endoscopy. Patients were divided into two groups: group "A" comprised patients with EA and group "B" those without EA. The variables analyzed were the clinical presentation, presence of HP, location, associated malformations, genetic disorders, and management.

RESULTS

 A total of 192 consecutive patients were included in the study: 51 (26.6%) in group A and 141 (73.4%) in group B. Indications for endoscopy in group B were eosinophilic esophagitis in 37 (19.2%) patients, celiac disease in 23 (11.95%) patients, and other disorders in 81 (42.2%) patients. Gastric HP was found in seven patients, all of them in group A. All lesions were hosted in the prepyloric antrum. The prevalence of HP in groups A and B was 13.7 and 0%, respectively (p < 0.05). Female gender was predominant in patients with AE and HP, this result being statistically significant (p = 0.044). No other associated malformation or genetic syndrome studied showed association with HP. Only one patient debuted with upper gastrointestinal (GI) bleeding and required excision, while six patients were asymptomatic. The mean follow-up was 54 months (range: 45-78 months).

CONCLUSION

 The incidence of gastric HP is more common in patients with EA, with the female gender being a risk factor for their association. Active search and follow-up is recommended as it may become symptomatic anytime and need resection.

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.

Adenocarcinoma arising from heterotopic pancreas at the first portion of the duodenum: a case report

Malignant transformation of a heterotopic pancreas in the duodenum is very rare. To our knowledge, only 15 cases have been reported worldwide, including the present case. We herein report a rare case of malignant transformation of a heterotopic pancreas in the duodenum along with a review of the literature.A 65-year-old man was admitted to our hospital for evaluation of dyspepsia and vomiting. Esophagogastroduodenoscopy showed a stricture of the duodenal bulb. Laparoscopic distal gastrectomy was performed. Although a duodenal tumor had not been suspected, histopathological examination of the surgical specimen showed adenocarcinoma arising from a heterotopic pancreas (Heinrich type III) in the duodenum. Four months postoperatively, the patient received adjuvant chemotherapy. He was still alive without recurrence at 24 months of follow-up.Adenocarcinoma arising in a heterotopic pancreas is rare; therefore, preoperative diagnosis is difficult to obtain. Effective management of a heterotopic pancreas depends on the presence or absence of symptoms. Awareness of the possibility of malignant change in a heterotopic pancreas of the duodenum prior to surgery is helpful for the diagnosis and appropriate management of such patients.

Pancreatic Heterotopia at the Gastroesophageal Junction: A Case Report and Review of the Literature

Pancreatic heterotopia is characterized by the presence of pancreatic tissue in a location outside of its typical anatomical position. Symptoms of pancreatic heterotopia vary based on the location of the ectopic tissue. It is commonly asymptomatic and often diagnosed incidentally during routine endoscopy. Clinically significant pancreatic heterotopia is often secondary to inflammation, bleeding, obstruction, and malignant transformation. The most common location of heterotopic pancreas is within 5 cm of the pylorus usually on the greater curvature. Involvement of the gastroesophageal junction is extremely rare. In this report, we describe the case of a 57-year-old woman who was diagnosed with ectopic pancreatic tissue at the gastroesophageal junction by esophagogastroduodenoscopy after presenting with symptoms of dyspepsia.

Extensive heterotopic pancreas in a rare site: A case report and a review of literature

RATIONALE

Heterotopic pancreas is a pancreatic tissue that occurs outside the normal anatomical site, the most common site is antrum. Due to the lack of specific imaging and endoscopic signs, heterotopic pancreas especially those occurring in the rare site, are often misdiagnosed, and leading to unnecessary surgical treatment. Endoscopic incisional biopsy and endoscopic ultrasound-guided fine-needle aspiration are effective means for diagnosing heterotopic pancreas. We reports a case of extensive heterotopic pancreas in a rare site, which was finally diagnosed by this way.

PATIENT CONCERNS

A 62-year-old man was admitted due to the presence of an angular notch lesion, which was suspected as gastric cancer before. He denied any history of tumor or gastric disease.

DIAGNOSES

No abnormality was found in the physical examination and laboratory testing after admission. Computed tomography showed localized thickening of the gastric wall measuring 30 mm in the long diameter. Gastroscope revealed a nodular-like submucosal protuberance at the angular notch with size of about 3*4 cm. Ultrasonic gastroscope showed that the lesion was located in the submucosa. The lesion exhibited mixed echogenicity. The diagnosis can not be identified.

INTERVENTIONS

2 times of incision biopsy were performed to make a clear diagnosis. Finally, appropriate tissue specimens were obtained for pathology testing.

OUTCOMES

The patient was diagnosed as heterotopic pancreas according to pathology. He was recommended to undergo observation and regular follow-ups rather than surgery. Then he was discharged home with no discomfort.

LESSONS

Heterotopic pancreas occurring in the angular notch is extremely rare, the site is scarcely reported in the relevant literature. Therefore, it is easy to be misdiagnosed. In the cases of an vague diagnosis, endoscopic incisional biopsy or endoscopic ultrasound-guided fine-needle aspiration may be a good choice.

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.

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.

Ultrasonic Features of Uncommon Congenital Heterotopic Colon and Pancreas in the Neck: An Extremely Rare Case Report

Congenital heterotopic colon and pancreas localized to the neck has not been reported. Herein, we describe an extremely uncommon case of congenital heterotopic colon and pancreas aberrantly presented within a cyst on the neck, and the thickened wall of the cyst on ultrasound may represent an important ultrasonic feature.

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).

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.

A case report of esophageal heterotopic pancreas presenting as recurrent mediastinal abscess, treated by minimally invasive esophagectomy

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Heterotopic pancreas is a rare congenital anomaly.

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Patients may present with complications such as inflammation and abscess.

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The management depends on size, ability to exclude other etiologies and symptoms.

Introduction

Heterotopic pancreas is a rare congenital anomaly. We report a case of esophageal heterotopic pancreas complicated by recurrent mediastinal abscess and treated by minimally invasive resection.

Presentation of case

A 31-year-old woman was admitted with a history of recurrent chest pain, dysphagia, and heartburn. CT scan revealed focal confined collection in the lower mediastinum surrounding esophagus. Endoscopic ultrasound revealed a subepithelial lesion. The patient was treated by minimally invasive esophagectomy and made an uneventful postoperative recovery.

Discussion

The management of subepithelial lesions would depend on their size, ability to exclude other etiologies and their associated symptoms. The patient, in this case, was obviously symptomatic and accurate differentiation from malignant etiologies could not be accurately made.

Conclusion

Although pancreatic heterotopia is rare, it should be remembered in the differential diagnosis of various gastrointestinal lesions.

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.

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.

Mesenteric heterotopic pancreas in a pediatric patient: A case report and review of literature

Heterotopic pancreas (HP) is a congenital anomaly defined as pancreatic tissue that has no contact with the orthotopic pancreas and its own duct system and vascular supply. The most common locations of HP are the upper gastrointestinal tract, specifically, the stomach, duodenum, and proximal jejunum. Involvement of the mesentery is rare. Here, we describe a rare case of mesenteric heterotopic pancreas (MHP) in a 12-year-old girl who presented with acute abdomen. The patient underwent emergency laparotomy, and the mass and adjacent small bowel were resected. Results of the postoperative histopathologic examination confirmed the diagnosis of MHP. Observation of the patient for 12 mo postoperatively showed no evidence of recurrence. Preoperative diagnosis of HP is difficult, even in a symptomatic patient. Increased awareness and understanding of the image characteristics of MHP will aid in correct preoperative diagnosis and appropriate patient management.

[Heterotopic tissue in the gastrointestinal tract]

Heterotopia of the gastrointestinal tract is a common finding. This is due to the complex embryogenesis and the relative ease to detect heterotopic tissue during endoscopy. The reason for biopsy is mostly to rule out neoplasms or to define specific causes of inflammation. Heterotopic tissue can occur in any location of the gastrointestinal tract. The most frequent are gastric heterotopia, pancreatic heterotopia, and heterotopia of Brunner's gland. On rare occasions, heterotopic tissue of salivary gland type as well as heterotopias of apocrine glands, thyroid, and prostatic tissue have been described. The most frequently involved organs are the small intestine, in particular the duodenum, the esophagus, and the stomach. Heterotopia of the large bowel occurs exclusively in the rectum. Most heterotopias do not cause symptoms and are easily diagnosed by biopsy and histology. However, depending on location, size, and the kind of underlying heterotopic tissue, they may cause significant complications, such as inflammation, ulceration and perforation, obstruction, intussusception, and severe life-threatening bleeding. Another rare but significant complication is neoplasia. Gastric heterotopias may give rise to pyloric gland adenomas within the bowel or rarely adenocarcinomas of the esophagus. Pancreatic heterotopia can be complicated by ductal type pancreatic adenocarcinomas, by acinus cell carcinomas, by intraductal papillary mucinous neoplasias, and also by endocrine tumors. The present paper summarizes our current knowledge about heterotopias in a topographic clinico-pathological manner.

Gastric heterotopic pancreas and stromal tumors smaller than 3 cm in diameter: clinical and computed tomography findings

BACKGROUND

Identifying gastric heterotopic pancreas and stromal tumors is difficult. Few studies have reported computed tomography (CT) findings for differentiating lesions less than 3 cm in diameter. In this study, we aimed to identify clinical characteristics and CT findings that can differentiate gastric heterotopic pancreatic lesions from stromal tumors less than 3 cm in diameter.

METHODS

A total of 132 patients with pathologically confirmed gastric heterotopic pancreas (n = 66) and stromal tumors (n = 66) were included. Each group was divided into primary (n = 50) and validation cohort (n = 16). Clinical characteristics and CT findings were retrospectively reviewed. CT findings included location, border, contour, growth pattern, enhancement pattern and grade, the enhancement value of tumor, enhancement ratio of tumor, and enhancement ratio of tumor to pancreas in venous phase. The findings in the two groups were compared using the Pearson χ² test or Student t-test. Receiver operating characteristic curves were used to determine areas under the curve and optimal cut-offs.

RESULTS

Significant differences were observed between heterotopic pancreas and stromal tumors in the distribution of tumor location, border, contour (all P < 0.001), enhancement values (P < 0.001), enhancement ratios of tumors (P < 0.001), and enhancement ratios of tumors to pancreas (P < 0.001). No significant differences existed in growth pattern (P = 0.203). The area under the curve differed significantly between enhancement ratio of tumor to pancreas and enhancement ratio (P = 0.030). There were significant differences in above characteristics between two groups in validation cohort.

CONCLUSIONS

Heterotopic pancreas has characteristic CT features differentiating it from stromal tumors.

Acute Clinical Manifestation of Mesenteric Heterotopic Pancreatitis: A Pre- and Postoperative Confirmed Case

Heterotopic pancreas is a relatively uncommon congenital anomaly, defined as pancreatic tissue in ectopic sites without an anatomic and vascular continuity with the main body of the pancreas. We report the case of a 58-year-old woman who was admitted to the hospital with the clinical suspicion of a mild, acute pancreatitis. Computed tomography, magnetic resonance imaging, transabdominal ultrasound, and endoscopic ultrasound revealed a normal orthotopic pancreas and the suspicion of a large heterotopic pancreas in the small bowel mesentery with signs of acute inflammation. The diagnosis of mesenteric heterotopic pancreatitis was preoperatively confirmed by endoscopic ultrasound-guided fine-needle aspiration and consequently histologically established after surgical resection.

Ectopic Pancreatic Tissue Adherent to the External Gallbladder Wall

Heterotopic pancreatic tissue can be found in the gastrointestinal tract, with the stomach and small bowel being the most common sites of localization. The gallbladder is seldom affected. Here, we report 2 cases of ectopic pancreas within the fatty tissue adherent to the organ wall. Both cases concerned young women (31 and 36 years old) who were treated with a laparoscopic cholecystectomy due to persistent abdominal symptoms thought to be related to chronic cholecystitis. Pathological examination revealed the presence of ectopic pancreatic tissue type 1.

Ectopic pancreas in the upper gastrointestinal tract: Is endosonographic diagnosis reliable? Data from the German Endoscopic Ultrasound Registry and review of the literature

Background:

Ectopic pancreas (EP) belongs to the most frequent subepithelial lesions (SELs) of the upper gastrointestinal (GI) tract. In the majority of cases, it is detected incidentally. Differential diagnosis from mesenchymal subepithelial tumors may be difficult.

Methods:

Among 24,308 endosonographic examinations and interventions, which were prospectively enrolled in the database of the German Endoscopic Ultrasound (EUS) Registry from January 2009 to August 2013, 575 were performed for suspected SELs of the upper GI tract. Sixty three cases of EP of the upper GI tract (stomach, n = 53; duodenum, n = 10; esophagus, n = 0) were extracted and retrospectively reviewed.

Results:

In 65.1% of cases, radial echoendoscopes or radial miniprobes were used for examination. Nearly 84% of EP was found in the stomach, 16% in the duodenum, none in the esophagus. In 88.9% of cases, the EUS examination discerned the layer of origin. In 59% of cases EP was described as a heterogeneous, in 28.6% as a homogeneous-hypoechoic and in 7.9% as a homogeneous-echogenic subepithelial mass lesion. Mean diameter was 13.0 mm × 8.1 mm, the mean ratio between long and short axis diameter was 1.75. EUS-guided fine needle aspiration (EUS-FNA) was used to accomplish cytological or histological diagnosis in only 6.3% of cases.

Conclusions:

EP accounts for 11% of all EUS examinations performed for subepithelial lesions of the upper GI tract and prospectively enrolled in the German EUS registry. Rather than being an eyecatcher, EP is a chameleon with numerous differential diagnoses. In selected cases, EUS-FNA may help clarifying the diagnosis.

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 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.