Heterotopic gastric mucosa in the anus and rectum: first case report of endoscopic submucosal dissection and systematic review

Gastric heterotopia in the rectum: a rare entity with potential pitfalls

Gastric heterotopia (GHT) is a medical condition where the gastric mucosa is found at a non-phyysiological part of the body. GHT can present itself anywhere in the gastrointestinal tract from the mouth to the anorectal area, as well as in the hepatobiliary system. However, it is relatively rare to find GHT in the rectum, with only around 50 documented cases reported in medical literature. We present the case of a 51-year-old man who underwent average-risk screening colonoscopy. He had no clinically significant comorbidities and was otherwise asymptomatic, with no family history. Notable findings included a pseudopolypoid lesion in the distal rectum, adjacent to the dentate line, measuring approximately 15 mm with regular-appearing mucosa under narrow-band-imaging. Biopsy specimens showed histological characteristics of oxyntic-type gastric mucosa without inflammation or dysplasia. GHT has the potential to progress to malignancy, although the rate of malignancy is currently unknown. Awareness of this entity is important given its frequency and potential for misdiagnosis.

Anal canal duplication with heterotopic gastric mucosa and anal stenosis: first case report and literature review

Introduction

Anal canal duplication (ACD) is a rare entity of gastrointestinal duplication that may be asymptomatic or present complications, such as abscess, fistulae, or malignant changes. The diagnosis and rational management of ACD still need to be clarified.

Case presentation

We present a case of an 18-month-old girl with intractable perianal erosion and painful bowel movements for one year, and chronic constipation for six months. Fistulography revealed a tubular structure (3 cm in length), located posterior to the native anal canal. Mucosectomy was performed through a perineal approach combined with a coccigeal approach, and the postoperative course was uneventful. The pathological findings confirmed the diagnosis of ACD with heterotopic gastric mucosa, a rare combination that has not been described in the literature before. A literature search was conducted on the Medline database for studies reporting ACD in children. The study pool consisted of 77 cases of ACD from 32 studies, including the present case. According to our case report and in line with the literature, 43 cases (55.84%) were incidentally found; the most frequent symptom was constipation (14.29%), followed by painful anal mass or sacral pain (10.39%), and recurrent fistula (7.79%). Coexisting diseases were observed in 31 patients (40.26%), including 19 (24.68%) cases associated with presacral masses. Surgical management was employed in 73 patients (94.81%). ACD excision was performed in 47 patients (64.38%), combined with presacral mass resection or coccygectomy in 19 cases (26.03%).

Conclusion

Preoperative imaging, including fistulography, ultrasonography, and magnetic resonance imaging, can provide useful information, especially for screening its associated anomalies. To prevent potential complications, surgical removal of ACD and associated anomalies is recommended. Mucosectomy may be one of the most effective surgical options for ACD due to its excellent functional outcome.

A case of atypical rectal tumor in a 55-years-old man?

A 55-year-old patient consulted a gastroenterologist in January 2023 because of recent-onset urgent diarrhea, without rectal bleeding or hematochezia. The patient has a history of diffuse large cell lymphoma with lymph node, bone and suspected small bowel involvement on 18F-FDG-PET/CT imaging, for which a differential diagnosis with a neuroendocrine tumor could not be formally made. He had no other medical or surgical history, and was a former smoker. Physical, digital rectal examinations and laboratory studies were unremarkable. A colonoscopy was performed and revealed a poly-poid soft formation of non-adenomatous appearance, measuring 30 mm x 30 mm.

An Unusual Case of Gastric Heterotopia Presenting as Rectal Prolapse

Heterotopic gastric mucosa (HGM) involving the rectum is an uncommon finding. It is especially rare in young children. Rectal prolapse is an uncommon presentation of HGM. We report a case of HGM in the rectum of a 2-year-old previously healthy girl, who presented with rectal prolapse and painless bleeding. Endoscopic mucosal resection was performed to completely resect the lesion after the patient failed to respond to proton pump inhibitors. This case underscores the importance of considering HGM involving the rectum as a cause of rectal prolapse in young pediatric patients.

Imaging Features of Ectopic Tissues and Their Complications: Embryologic and Anatomic Approach

Ectopic tissue is an anatomic abnormality in which tissue develops in an area outside its normal location. It is primarily caused by abnormalities during the process of embryologic development. Although the majority of individuals with ectopic tissues remain asymptomatic, various symptoms and associated complications can occur. Failure in normal embryologic development leads to loss of normal physiologic function or may result in harmful functions such as ectopic hormonal secretion in the ectopic pituitary adenoma. Ectopic tissues may also frequently mimic tumors. For example, developmental abnormalities in the pharyngeal pouches may result in an ectopic parathyroid gland and ectopic thymus, both of which are frequently misdiagnosed as tumors. Adequate knowledge of embryology is essential for understanding the differential diagnoses of ectopic tissues and facilitating appropriate management. The authors summarize the embryologic development and pathogenesis of ectopic tissues by using illustrations to facilitate a deeper understanding of embryologic development and anatomy. Characteristic imaging findings (US, CT, MRI, and scintigraphy) are described for ectopic tissues of the brain, head, neck, thorax, abdomen, and pelvis by focusing on common conditions that radiologists may encounter in daily practice and their differential diagnoses. ^©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center.

Life-threatening gastrointestinal bleeding caused by jejunal heterotopic gastric mucosa in an adult dog: a rare case report

Background

Heterotopic gastric mucosa has been scarcely reported in the veterinary literature. Its presence can be asymptomatic or associated with various clinical signs ranging from apathy, vomiting, to abdominal pain. This report illustrates the presence of heterotopic gastric mucosa in the jejunum of an adult dog. It is the first to describe severe anemia, requiring acute blood transfusion, following intestinal hemorrhage caused by heterotopic gastric mucosa.

Case presentation

A twelve-year-old, intact male Maltese dog was presented with a history of apathy, vomiting and anemia. The dog was on a strict diet for recurrent diarrhea, food intolerance and skin allergy. Clinical examination revealed severe anemic mucous membranes and painful abdominal palpation. Blood examination confirmed severe regenerative anemia. Ultrasonography showed an intestinal neoplasm, gall bladder sludge and non-homogeneous liver parenchyma. Three-view thoracic radiographs failed to show any metastatic lesions or enlarged lymph nodes. After initial stabilization and blood transfusion, a midline exploratory laparotomy was performed. Three different masses were found in the jejunum. Resection and anastomosis of approximately 40 cm of jejunum was performed, followed by liver and lymph node biopsy and placement of an esophagostomy tube. Two days after surgery the dog started to clinically improve and was discharged from the hospital on the sixth day after surgery. Histopathology revealed the intestinal masses to be heterotopic gastric mucosa associated with intramural cystic distensions, multifocal ulceration and bleeding into the intestinal lumen. Two years after surgery, the dog did not have a recurrence of anemia or gastrointestinal signs.

Conclusions

This case demonstrates that heterotopic gastric mucosa can be considered one of the differential diagnoses in case of severe anemia due to gastrointestinal hemorrhage and suspected intestinal tumors. Although in most described cases in literature the finding seems to be incidental on necropsy, our report shows that heterotopic gastric mucosa can be the etiology of life-threatening signs. In addition, because no recurrent diarrhea episodes occurred after surgical resection of the ectopic tissue, it is likely that the heterotopic gastric mucosa was the cause of the food intolerance signs in this dog.

Gastric heterotopia of colon found cancer workup in liver abscess: A case report

BACKGROUND

Recently reported cases of pyogenic liver abscess associated with colonic cancer in the absence of underlying disease, have included a small number of cases of gastric heterotopia (GHT). GHT is a congenital anomaly composed of ectopic gastric mucosa and can occur anywhere in the gastrointestinal tract but is more frequently encountered in the cervical esophagus. However, it is rarely observed in colon. Furthermore, most reported cases of GHT of the colon involved the rectum, and GHT involving the colon proximal to the rectum is rare.

CASE SUMMARY

An 83-year-old male patient presented with fever and a diagnosis of pyogenic liver abscess. Colonoscopy was performed for colon cancer workup and revealed a 1.0 cm sized polyp at the transverse colon. The polyp was removed by endoscopic mucosal resection by monopolar electrocauterization using a snare. Pathological examination revealed GHT. After administering intravenous antibiotics, the patient recovered well.

CONCLUSION

GHT in the colon could affect the development of pyogenic liver abscess by enabling hematogenous propagation of Klebsiella pneumoniae through mucosal damage. However, more study is needed due to the lack of cases.

Heterotopic Gastric Mucosa Causing Rectal Bleeding in a Young Child

Heterotopic gastric mucosa (HGM) in the colon and small bowel is a very rare finding. We report a case of HGM in the rectum of an 8-year-old child with a history of eosinophilic esophagitis after having a colonoscopy to evaluate for inflammatory bowel disease. The colonoscopy was normal except for rectal tissue erythema and edema. Inflammatory bowel disease has been reported in some cases of children with eosinophilic changes of the esophagus. The child had intermittent rectal bleeding thought to be due to constipation. Interestingly, when the patient was placed on a proton pump inhibitor for the treatment of eosinophilic esophagitis, the rectal bleeding decreased. After our patient ceased proton pump inhibitor therapy, he experienced a large amount of rectal bleeding. Histological findings revealed HGM in the colon/rectum. An extensive review of the incidence, diagnosis, and treatment is discussed.

[Heterotopic Salivary Gland Tissue at the Hepatic Flexure of the Large Intestine: A Case Report]

The occurrence of heterotopic tissue in the large intestine is unusual. The most common heterotopic tissue type described is gastric-type mucosa. On the other hand, heterotopic salivary gland tissue in the large intestine is extremely rare. To the best of the authors' knowledge, only five cases of heterotopic salivary gland in the large intestine have been reported, and all cases arose in the left colon. One out of five cases arose in the sigmoid colon, and the four other cases were found in the rectum-anal canal region. Endoscopically, they usually appeared as a polyp. The presentation of the patients was rectal bleeding or asymptomatic. Heterotopic salivary gland tissue in the colon has not been reported in Korea. This paper reports a case of heterotopic salivary gland tissue at the hepatic flexure of the colon and reviews the literature on similar cases. A 55-year-old male underwent large bowel endoscopy for colorectal carcinoma screening. The colonoscopy revealed five polyps. A sessile polyp at the hepatic flexure, 0.6 cm in size, was resected in a piecemeal manner. The histopathologic findings revealed a salivary gland with mixed mucinous-serous features and ducts. The other four polyps all were diagnosed as tubular adenoma with low-grade dysplasia.

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.

Heterotopic Respiratory Mucosa in the Rectum: An Unusual Type and Site of Heterotopia in the Gastrointestinal Tract

Although pancreatic and gastric heterotopias are common findings in the gastrointestinal tract, heterotopic respiratory mucosa (HRM) in the rectum is extremely rare and has only been reported twice previously. We are presenting, to our knowledge, the third case of HRM in the rectum. A 56-year-old man with a history of chronic diarrhea presented for diagnostic colonoscopy, where he was found to have a rectal subepithelial nodule. He was subsequently referred to a tertiary medical center for further evaluation with rectal endoscopic ultrasound. Endoscopically, the nodule was hypoechoic, 2 to 3 mm in size, located in the submucosa, and did not appear to invade the muscularis propria. An uncomplicated endoscopic submucosal resection was subsequently performed. Microscopically, the nodule showed a multicystic complex lesion located in the submucosa, lined by ciliated pseudostratified columnar epithelium and surrounded by thin to moderately thick smooth muscle bundles and multiple lobules of seromucinous glands. There was associated acute and chronic inflammation. The rectum overlying the subepithelial lesion was lined by congested and edematous colonic mucosa and demonstrated no connection with the underlying cystic lesion. Immunohistochemical stains showed positive p63 basal cell staining in the respiratory epithelium of the lesion, while CDX2, TTF-1, and estrogen receptors were all negative. HRM is a benign nonneoplastic lesion with unclear etiology. Pathologists and gastroenterologists should be aware of this entity and consider it in their differential diagnosis for a subepithelial nodule in the rectum, keeping in mind that neoplastic processes can also develop in this location.

Large heterotopic gastric mucosa and a concomitant diverticulum in the rectum: Clinical experience and endoscopic management

Heterotopic gastric mucosa (HGM) in the rectum is an extremely rare clinical entity which may be missed or misdiagnosed due to a lack of knowledge. In the present study, a 14-year-old girl visited our hospital due to a 5-year history of repeated hematochezia. Colonoscopy showed a solitary superficial depressed lesion approximately 5 cm in size and a concomitant 1.5 cm deep diverticulum in the rectum. Histological examination of the endoscopic biopsy showed typical ectopic gastric mucosa in the depressed lesion and inside the diverticulum. Narrow band imaging further confirmed the histological results. Endoscopic ultrasound indicated that the lesion originated from the mucosal layer, and partially involved the submucosal layer. Endoscopic submucosal dissection was performed in this patient due to the large size and shape of the lesion. No bleeding, perforation or other adverse events were observed. The presence of HGM in the diverticular cavity greatly increased the surgical difficulty. A literature review was also carried out in our study.

Endoscopic Mucosectomy in a Child Presenting with Gastric Heterotopia of the Rectum

Gastric mucosal heterotopia has been described in all levels of the gastrointestinal tract. Its occurrence in the rectum is uncommon. We report the case of a 4-year-old boy referred to Pediatric Gastroenterology for intermittent rectal bleeding for the past 2 years. Total ileocolonoscopy revealed a flat, well-circumscribed lesion of 4 cm, with elevated margins, localized at 10 cm from the anal verge. Histologic examination showed typical gastric mucosa of the oxyntic type. Treatment with proton pump inhibitors was started without resolution of the symptoms and, therefore, an endoscopic mucosal resection was performed. Heterotopic gastric mucosa represents a rare cause of rectal bleeding in children and endoscopic evaluation is fundamental for diagnosis. Although not usually performed in pediatric ages, endoscopic mucosectomy allows complete resolution of the problem avoiding surgery.

Colorectal endoscopic submucosal dissection: predictors and neoplasm-related gradients of difficulty

BACKGROUND AND STUDY AIM

 The role of colorectal endoscopic submucosal dissection (ESD) is standardized in Japan and East Asia, but technical difficulties hinder its diffusion. The aim was to identify predictors of difficulty for each neoplasm type.

METHODS

 A competent operator performed all procedures. ESD difficulty was defined as: en bloc with a slow speed (< 0.07 cm ² /min; 30 × 30 mm neoplasm in > 90 min), conversion to endoscopic mucosal resection, or resection abandonment. Pre- and intraoperative difficulty variables were defined according to standard criteria, and evaluated separately for the rectum and colon. Difficulty predictors and gradients were evaluated by the multivariate logistic regression model.

RESULTS

 A total of 140 ESDs were included: 110 in the colon and 30 in the rectum. Neoplasms were laterally spreading tumors - granular type (LST-G) in 85 cases (61 %); the median longer axis was 30 mm (range 15 - 180 mm); a scar was present in 15 cases (11 %). ESD en bloc resection and difficulty rates were 85 % (n = 94) and 35 % (n = 39) in the colon, and 73 % (n = 22) and 50 % (n = 15) in the rectum ( P  = 0.17 and 0.28, respectively). The scar was the only preoperative predictor of difficulty in the rectum (odds ratio [OR] 12.3, 95 % confidence interval [CI] 1.27 - 118.36), whereas predictors in the colon were: scar (OR 12.7, 95 %CI 1.15 - 139.24), LST - nongranular type (NG) (OR 10.5, 95 %CI 1.20 - 55.14), and sessile polyp morphology (OR 3.1, 95 %CI 1.18 - 10.39). Size > 7 - ≤ 12 cm ² (OR 0.20, 95 %CI 0.06 - 0.74) and operator experience > 120 procedures (OR 0.19, 95 %CI 0.04 - 0.81) were predictors for a easy procedure. No intraoperative predictors of difficulty were identified in the rectum, whereas predictors in the colon were: severe submucosal fibrosis (OR 21.9, 95 %CI 2.11 - 225.64), ineffective submucosal exposure by gravity countertraction (OR 12.3, 95 %CI 2.43 - 62.08), and perpendicular submucosal dissection approach (OR 5.2, 95 %CI 1.07 - 25.03). When experience was /= 90, preoperative gradient of colonic ESD difficulty was the highest for LST-NGs (scar positive and negative up to 47 % and 20 %, respectively), intermediate for sessile polyps with scar (up to 23 %), and the lowest for LST-Gs (< 8 %). Different difficulty gradients between neoplasm types persisted with increasing experience: LST-NG rate up to 14 % after 120 procedures.

CONCLUSIONS

 Colonic and rectal ESD difficulty has qualitative differences. Preoperative predictors should be considered to identify the difficulty gradient of each neoplasm type and the appropriate setting for ESD.

Heterotopic Gastric Mucosa in a Duplication Cyst of the Common Hepatic Duct Mimicking Cholangiocarcinoma

Heterotopic gastric mucosa in biliary tract is a congenital anomaly that can prove significant clinical dilemmas. Here we report the case of a 28-year-old female patient presenting with jaundice, pruritus, and altered liver tests, with predominant cholestasis. Liver biopsy revealed histological changes suggesting large bile duct obstruction with advanced fibrosis. At imaging, common hepatic duct stricture due to an intraluminal enhancing mass was observed. Endoscopic retrograde cholangiopancreatography and upper echoendoscopy revealed a firm mass of the common hepatic duct with a complete obstruction, suspicious for cholangiocarcinoma. Fine-needle aspiration biopsy performed under echoendoscopic guidance revealed fundic type gastric mucosa. Despite histological result, radiological suspicion of malignancy together with advanced fibrosis prompted a segmental resection of biliary tract. At macroscopic examination, the common hepatic duct presented a focal pseudocystic appearance with a firm zone of subtotal stenosis. Histology revealed a duplication cyst lined by heterotopic fundic gastric mucosa. Heterotopic gastric mucosa of the biliary tract should be suspected in young patients without know risk factors for hepatobiliary malignancies. Imaging and careful histological examination are mandatory for optimal management. Liver fibrosis, secondary to chronic biliary obstruction may be a significant late complication.

Gastric heterotopia in rectum: A literature review and its diagnostic pitfall

Objectives:

The term heterotopia, in pathology, refers to the presence of normal tissues at foreign sites. Gastric heterotopia has been reported anywhere in the gastrointestinal tract. However, the presence of gastric heterotopia in the rectum is very rare.

Methods:

We, here, report a rare case of a localized 2-cm area of cratered mucosa with heaped-up borders in the rectum of a 51-year-old, asymptomatic woman who underwent screening colonoscopy.

Results:

Histologic examination of the biopsy from the lesional tissue in rectum demonstrated fragments of rectal mucosa co-mingling with oxyntic- and antral-type gastric mucosa. No intestinal metaplasia or Helicobacter pylori is identified.

Conclusion:

Patients with gastric heterotopia in rectum usually present with bleeding and/or abdominal pain. Definite treatment of choice is surgical or endoscopic resection, although the lesions also respond to histamine-2 receptor blockers. In this article, most recent literature about gastric heterotopia in rectum is reviewed, following a case presentation about it.