Unusual gastric polyp showing submucosal proliferation of glands: case report and literature review

Clinicopathologic and endoscopic characteristics of ten patients with gastric hamartomatous inverted polyp: a single center case series

BACKGROUND

Gastric hamartomatous inverted polyps (GHIPs) are not well characterized and remain diagnostically challenging due to rarity. Therefore, this study aims to investigate the clinicopathologic and endoscopic characteristics of patients with GHIP.

METHODS

We retrospectively reviewed clinicopathologic and endoscopic features of ten patients with GHIP who were admitted to Beijing Friendship Hospital from March 2013 to July 2022. All patients were treated successfully by endoscopic resection.

RESULTS

GHIPs were usually asymptomatic and found incidentally during gastroscopic examination. They may be sessile or pedunculated, with diffuse or local surface redness or erosion. On endoscopic ultrasonography, the sessile submucosal tumor-type GHIP demonstrated a heterogeneous lesion with cystic areas in the third layer of the gastric wall. Histologically, GHIPs were characterized by a submucosal inverted proliferation of cystically dilated hyperplastic gastric glands accompanied by a branching proliferation of smooth muscle bundles. Inflammatory cells infiltration was observed in the stroma, whereas only one patient was complicated with glandular low-grade dysplasia. Assessment of the surrounding mucosa demonstrated that six patients (60%) had atrophic gastritis or Helicobacter pylori-associated gastritis, and four patients (40%) had non-specific gastritis. Endoscopic resection was safe and effective.

CONCLUSIONS

GHIPs often arise from the background of abnormal mucosa, such as atrophic or H.pylori-associated gastritis. We make the hypothesis that acquired inflammation might lead to the development of GHIPs. We recommend to make a full assessment of the background mucosa and H. pylori infection status for evaluation of underlying gastric mucosal abnormalities, which may be the preneoplastic condition of the stomach.

Large gastric hamartomatous inverted polyp accompanied by advanced gastric cancer: A case report

BACKGROUND

Gastric hamartomatous inverted polyps (GHIPs) are benign polyps of the gastric submucosal layer. Currently there are 52 reported cases in the English literature. According to a literature review, approximately 27% of GHIPs show a coexisting carcinoma.

CASE SUMMARY

A 66-year-old man was referred to our institution with ulcerative lesions detected on esophagogastroduodenoscopy (EGD) during a regular check-up. Other medical findings were nonspecific. The lesions had borderline histologic features that could not exclude malignancy and were followed up with three EGDs and biopsies at intervals of 3 mo. The latest biopsy was revealed as an adenocarcinoma. A total gastrectomy was performed to remove the tumor. The surgical specimen revealed a 6.9 cm × 4.5 cm sized GHIP with a coexisting 1.6 cm sized well-differentiated adenocarcinoma which extended to the muscularis propria. The malignancy did not originate from the GHIP but showed an overlap.

CONCLUSION

A large GHIP, which was unusually presented as an ulcerative lesion, was surgically removed, and was accompanied by advanced gastric cancer. Regular follow-up and thorough examinations of ulcerative lesions with equivocal biopsy have resulted in appropriate diagnosis and treatment. Therefore, aggressive intervention may be beneficial if GHIP is suspected.

Diagnosis and treatment of gastric hamartomatous inverted polyp (GHIP) by endoscopic submucosal dissection: A case report

RATIONALE

Gastric hamartomatous inverted polyps (GHIP) is not a common disease, and it has rarely been reported in the literature. Preoperative diagnosis is difficult due to the deep position and surface covered with normal gastric mucosa. However, with the progress of endoscopic technology, endoscopic submucosal dissection (ESD) can play a crucial role in the diagnosis and treatment of GHIP.

PATIENT CONCERNS

A 61-year-old Chinese man underwent gastroscopy due to abdominal pain 2 months prior that revealed chronic superficial nonatrophic gastritis with erosion and a submucosal tumor in the gastric body (an ultrasound gastroscopy was recommended). Therefore, he was admitted to our hospital for further diagnosis and treatment.

DIAGNOSES

A hemispherical submucosal tumor was found in the middle segment of the stomach, with a size of approximately 30 mm × 35 mm and a smooth surface without central ulceration or mucosal bridge formation. Ultrasound gastroscopy showed that the lesion was a hypoechoic mass with uniform internal echo originating from the muscularis propria.

INTERVENTIONS

The tumor was completely removed by using ESD. The postoperative pathological results indicated a monocystic structure in the submucosa that was not connected with the surface mucosa. The surface of the cyst was covered with foveolar cells and mucous-neck cells (part of which had low-grade intraepithelial neoplasia), and GHIP was considered to be diagnosed.

OUTCOMES

According to the abovementioned endoscopic and pathological features, the patient was finally diagnosed with GHIP. The patient was successfully discharged after surgery and received regular follow-up observations.

LESSONS

GHIP is located in the submucosa layer and has the potential risk of malignant transformation. However, it is not easy to diagnose by using gastroscopy and ultrasound gastroscopy. ESD can obtain complete specimens, which contributes to the diagnosis and treatment of GHIP.

Autoimmune gastritis with a gastric hamartomatous inverted polyp and two hyperplastic polyps: a case report

We report an unusual case of autoimmune gastritis (AIG) complicated with a submucosal tumor (SMT) and two pedunculated polyps in a 60-year-old man. The patient was admitted for epigastric distention, heartburn, and anorexia. Endoscopy showed an SMT in the fundus, two pedunculated polyps in the body, and markedly atrophic mucosa of the body and fundus. The SMT, measuring 20 mm in diameter, was resected by endoscopic submucosal dissection and histologically diagnosed as a gastric hamartomatous inverted polyp (GHIP), which is characterized by submucosal glandular proliferation, cystic dilatation, and calcification. The gland structures consisted of foveolar cells and pseudopyloric or mucous-neck cell types. The two pedunculated polyps that were resected by endoscopic mucosal resection were histologically diagnosed as hyperplastic polyps, which are characterized by hyperplastic foveolar glands with pseudopyloric or mucous-neck glands in the inflamed stroma in the mucosa, which consisted of almost the same types of lining cells as the GHIP in the fundus. Findings may indicate the relationship between GHIP, hyperplastic polyp, and AIG. We highlight considering GHIP as a differential diagnosis for an SMT in patients with AIG.

Gastric hamartomatous inverted polyp: Report of three cases with a review of the endoscopic and clinicopathological features

Objectives

A gastric hamartomatous inverted polyp (GHIP) is a rare submucosal tumor characterized histopathologically by a submucosal inverted proliferation of cystically dilated hyperplastic gastric glands. Only 42 GHIPs have been reported in English literature. Few GHIPs have been reported to accompany adenocarcinomas. We reported on three patients with a GHIP and reviewed the clinicopathological and endoscopic features of GHIPs.

Methods

This study included two men and one woman with a GHIP. The endoscopic, histopathological, and immunohistochemical features of the endoscopically resected specimens were analyzed. A gene mutation analysis was also performed.

Results

All the tumors were located in the body of the stomach, with a median size of 20 mm. Two tumors were sessile, and the remaining tumor had a pedunculated appearance. The overlying mucosa mainly appeared normal but was reddish in one tumor. The histopathological examination of the tumors revealed a well-circumscribed and lobular submucosal proliferation of cystically dilated hyperplastic glands. The immunohistochemical analysis revealed that the MUC5AC-positive foveolar epithelium was located in the center, and MUC6-positive pseudo-pyloric or pepsinogen-I and H⁺/K⁺ ATPase-positive fundic-type glands were located at the periphery of two tumors. No carcinomatous components were noted in any of the tumors. Moreover, no significant mutations in oncogenes or tumor suppressor genes were noted.

Conclusions

Our review revealed that approximately three fourths of GHIP cases showed an submucosal tumor-like feature, whereas endoscopic features, including the endoscopic ultrasonography findings, were not characteristic. Because an endoscopic diagnosis of a GHIP may be difficult, complete endoscopic resection may be required for a pathological diagnosis.

Gastric inverted hyperplastic polyp: A case report

Inverted hyperplastic polyp (IHP) is a rare disease characterized by the downward growth of proliferative mucosal components into the submucosal layer. It is often misdiagnosed as other submucosal tumors and accurate diagnosis requires pathological examination. Most patients with IHP have no clinical symptoms and some have non-specific symptoms, such as abdominal distension, abdominal pain and even anemia. IHP is treated via endoscopic mucosal resection or endoscopic sub-mucosal section. The present study reported a case of IHP and discussed its clinical manifestations, clinicopathological diagnosis, differential diagnosis and treatment to improve our understanding of the disease.

Gastric adenocarcinoma arising from hamartomatous inverted polyp during 8‐year follow‐up

Gastric hamartomatous inverted polyp (GHIP) is rare, with few reports of carcinogenesis from GHIP during long‐term follow‐up. A 51‐year‐old woman was diagnosed as having a submucosal tumor (SMT) during esophagogastroduodenoscopy (EGD) in 2008. In 2016, although the size and height of the lesion had not changed, she was referred to our hospital for further investigation of the lesion. EGD depicted a gastric SMT of 20 mm in diameter in the greater curvature of the upper gastric body, and a biopsy specimen showed a well to poorly differentiated adenocarcinoma. Following successful laparoscopic total gastrectomy, histopathological examination revealed an intramucosal adenocarcinoma arising in GHIP.

Gastric Inverted Polyps-Distinctive Subepithelial Lesions of the Stomach: Clinicopathologic Analysis of 12 Cases With an Emphasis on Neoplastic Potential

Gastric inverted polyps (GIPs) are rare gastric polyps characterized by a submucosal inverted growth of mucosal components. Because of their rarity, they are not well characterized and are diagnostically challenging. We examined 12 cases of GIPs arising in 8 male and 4 female patients (mean age: 56 y). Most GIPs (11/12, 92%) occurred as a single, rounded subepithelial lesion in the body or fundus (mean size: 14.9 mm). Histologically, GIPs consisted of gastric-type glandular epithelium and smooth muscle component, growing in an endophytic manner; however, they displayed significant morphologic variations. We classified GIPs into 3 subtypes by the following features: communication with the mucosal surface, smooth muscle boundary, and tissue organization. The defining characteristics of type 1 were a mucosal communicating structure at the center and a well-defined smooth muscle boundary, resulting in a characteristic low-magnification morphology of a round vase. Type 2 had an organized glandular proliferation with smooth muscle boundary and no central communicating structure. Type 3 GIPs had no mucosal communicating structure or smooth muscle boundary; its key histologic feature was the lobular organization pattern produced by proliferations of cystic or hyperplastic glands and smooth muscle. All type 1 GIPs exhibited coexisting adenocarcinoma (3 cases) or stromal proliferation (3 cases). Three patients with type 2 GIP had separate adenocarcinoma. None of the type 3 GIPs had accompanying carcinoma. In conclusion, GIPs are a heterogenous group showing different morphology and clinical behavior. Notably, type 1 GIP could be considered a precancerous lesion with the potential to develop adenocarcinoma.

Gastric MiNEN Arising from the Heterotopic Gastric Glands

An 80-year-old woman presented with a 30-mm protruding lesion-like submucosal tumor with a central depression located at the anterior wall of the upper gastric body. The depressed area had a well-demarcated margin, while the other area was covered by a non-neoplastic mucosa. A biopsy specimen revealed neuroendocrine carcinoma. Endoscopic ultrasonography revealed a heterogeneous mass with a clearly distinguished border in the submucosal layer. The mass had two distinct areas adjacent to each other. In addition, a hypoechoic zone was observed on the margin of the mass. Distal gastrectomy was performed. The final diagnosis was a mixed neuroendocrine-non-neuroendocrine neoplasm arising from the heterotopic gastric gland.

Diagnosis and treatment of gastric hamartomatous inverted polyp (GHIP) using a modified combination of laparoscopic and endoscopic approaches to neoplasia with a non-exposure technique (modified CLEAN-NET): a case report

BACKGROUND

Gastric hamartomatous inverted polyp (GHIP) is a pathological condition where enlarged gastric glands with cystic dilatation grow in the submucosa. It is difficult to excise the tissue due to its location. In addition, even if the tissue is taken correctly, making an accurate diagnosis is difficult due to foveolar epithelium in the tissue, which can be misdiagnosed as gastric mucosal epithelium. Thus, an accurate diagnosis of GHIP is rarely established from a biopsy alone preoperatively. We here report a case of GHIP with a central dimple, which was diagnosed and treated using a modified combination of laparoscopic and endoscopic approaches to neoplasia with a non-exposure technique (modified CLEAN-NET).

CASE PRESENTATION

A 60-year-old man with a submucosal tumor (SMT) in the stomach was referred to our hospital by a primary care doctor. On examination, a gastrointestinal stromal tumor was suspected. Modified CLEAN-NET was performed for diagnostic and therapeutic purposes. The histopathological examination of the resected specimen showed an enlarged gland duct in the submucosal layer. This finding, along with immunostaining results, led to the diagnosis of GHIP. The postoperative course was uneventful without any symptoms.

CONCLUSIONS

GHIP should be considered among the differential diagnoses of SMT of the stomach. Modified CLEAN-NET may be beneficial in the removal of SMTs such as GHIP with a central dimple because it can avoid stomach deformation of the stomach and tumor dissemination.

Early gastric cancer with multiple submucosal heterotopic gastric gland: A case report

A case of early gastric cancer involving multiple submucosal gastric glands that was treated by distal gastrectomy was described in the present case report. An 85-year-old man was referred to our hospital for the treatment of gastric cancer. Esophagogastroduodenoscopy revealed an irregular, nodular, elevated lesion on the posterior wall of the middle third of the stomach, and biopsy specimens indicated well-differentiated tubular adenocarcinoma. Submucosal tumor (SMT)-like lesions were detected in the area adjacent to the nodular lesion, in the anterior wall side of the middle third of the stomach. Abdominal contrast-enhanced computed tomography showed cystic lesions in the middle part of the stomach, and no mass lesions in the liver. The patient underwent distal gastrectomy with regional lymphadenectomy. Macroscopic examination of the resected specimen showed an SMT-like lesion measuring 2.8×2.6 cm in contact with a superficial, depressed lesion measuring 1.7×0.9 mm in the middle third of the stomach, and another SMT-like lesion measuring 1.5×1.4 cm in diameter, which was also in the middle third of the stomach. The pathological diagnosis was well-differentiated tubular adenocarcinoma invading the gastric submucosal layer without lymph node metastasis, but with nearby submucosal heterotopic gastric gland (SHGG) detected. Following surgery, the patient remained symptom-free without evidence of recurrence for 3 months. The finding of SHGG remains a rare entity, and further studies are warranted to clarify the association between these submucosal lesions and the development of cancer.

A disconcerting false gastric diverticulum mimicking malignancy

Gastric diverticula are the most uncommon form of gastrointestinal diverticula. They can either be of true or false type with different pathogenesis. They may be very challenging to diagnose as symptoms are nonspecific and imaging can simulate a malignant lesion. We report an unusual case of pre-pyloric diverticulum in a 69-year-old man, leading to severe gastric obstruction with a poor general condition. As subsequent endoscopy and imaging were alarming and couldn't exclude malignancy, the patient underwent an antrectomy. The final diagnosis was made on pathological examination. We discuss, through this case, the clinical and pathological features of gastric diverticula with an emphasis on the pathogenesis of this rare entity and the risk of a malignant transformation.

[Inverted Hyperplastic Polyp in Stomach: A Case Report and Literature Review]

An inverted hyperplastic polyp (IHP) found in stomach is rare and characterized by downward growth of hyperplastic mucosal component into the submucosa. Because of such characteristic, IHP can be misdiagnosed as subepithelial tumor or malignant tumor. In fact, adenocarcinoma was reported to have coexisted with gastric IHP in several previous reports. Because only 18 cases on gastric IHP have been reported in English and Korean literature until now, pathogenesis and clinical features of gastric IHP and correlation with adenocarcinoma have not been clearly established. Herein, we report a case of gastric IHP which was initially misdiagnosed as gastrointestinal stromal tumor and resected using endoscopic submucosal dissection. Literature review of previously published case reports on gastric IHP is also presented.

A case of gastric hamartomatous inverted polyp resected endoscopically

We report the case of a 55-year-old woman with a tumor in the greater curvature of the upper gastric body. The tumor was incidentally found on an upper gastrointestinal X-ray series performed during a routine medical examination. Whereas endoscopy revealed a gastric submucosal tumor (SMT), endoscopic ultrasonography demonstrated a heterogeneous tumor with small, cystic, hypoechoic spots originating from the second layer. The patient was clinically asymptomatic, with no contributory family history or abnormal laboratory data. The results of a physical examination, abdominal computed tomography, and plain chest radiography were all unremarkable. Although the endoscopic tumor type was determined to be SMT, the tumor was successfully resected by endoscopic submucosal dissection (ESD) and subsequently diagnosed as a gastric hamartomatous inverted polyp (GHIP). The findings of the present case highlight the importance of considering GHIP as a diagnosis and indicate the utility of en bloc resection of GHIP with ESD.

Gastric inverted hyperplastic polyp: A rare cause of iron deficiency anemia

Gastric inverted hyperplastic polyp (IHP) is a rare gastric polyp characterized by the downward growth of hyperplastic mucosal components into the submucosal layer. Macroscopically, a gastric IHP resembles a subepithelial tumor (SET); as a result, accurately diagnosing gastric IHP is difficult. This issue has clinical significance because gastric IHP can be misdiagnosed as SET or as malignant neoplasm In addition, adenocarcinoma can accompany benign gastric IHP. Although in most cases, gastric IHPs are asymptomatic and are found incidentally, these polyps may cause anemia secondary to chronic bleeding. Here, we report one case involving gastric IHP accompanied by chronic iron deficiency anemia that was successfully managed using endoscopic submucosal dissection.

Gastric Hamartomatous Polyps-Review and Update

Gastric polyps are frequently encountered on endoscopic examinations. While many of these represent true epithelial lesions, some of the polyps may result from underlying stromal or lymphoid proliferations or even heterotopic tissue. Histologic examination is essential for accurate typing of the polyps to predict malignant potential and underlying possible genetic abnormalities. The focus of this review is on gastric hamartomatous polyps, which are relatively rare and diagnostically challenging. Though most of the gastric hamartomatous polyps are benign, certain types are associated with increased malignant potential. These include certain polyps associated with specific genetic familial polyposis syndromes and gastric inverted hamartomatous polyps. Identification of these polyps can result in the prevention or early diagnosis of gastric carcinoma and also help in the identification of family members with polyposis syndromes. The aim of this review is to categorize gastric hamartomatous polyps and aid in the identification of high-risk categories.

Gastric inverted hyperplasic polyp composed only of pyloric glands: a rare case report and review of the literature

Inverted hyperplastic polyp (IHP) in stomach is a rare benign gastric polypoid lesion, characterized by downward growth of hyperplastic mucosal glands into the submucosal layer. In most previous reported cases, gastric IHP showed mixtures of fundic-type gland, pyloric-type gland, and foveolar-type epithelium. Also, a case of IHP composed of only one type of gland is extremely rare. This report describes a case of a 70-year-old man with gastric IHP, composed only of pyloric-type gland. It was removed completely by endoscopic submucosal dissection, and patient showed no recurrence over 2 years after treatment.

Two rare gastric hamartomatous inverted polyp cases suggest the pathogenesis of growth

Gastric hamartomatous inverted polyps (GHIP) are difficult to diagnose accurately because of inversion into the submucosal layer. GHIP are diagnosed using the pathological characteristics of the tumor, including the fibroblast cells, smooth muscle, nerve components, glandular hyperplasia, and cystic gland dilatation. Although Peutz-Jeghers syndrome, juvenile polyposis, and Cowden disease are hereditary, it is rare to encounter 2 cases of monostotic and asymptomatic gastric hamartomas. The pathogeneses of hamartomatous inverted polyps and inverted hyperplastic polyps remain controversial because of the paucity of reported cases. There are 3 hypotheses regarding the pathogenesis of complete gastric inverted polyps. Based on our experience with 2 successive, rare GHIP cases, we affirm the hypothesis that after a hamartomatous change occurs in the submucosal layer, some of these components are exposed to the gastric mucosa and, consequently, form a hypertrophic lesion. In Case 1, our hypothesis explains why a tiny hypertrophic change was first detected on the top of the submucosal tumor using a detailed narrow band imaging-magnified endoscopy. There was no confirmation that the milky white mucous and calcification structures were exuding directly from the biopsy site like Case 1, and in Case 2 the presence of this mucous was indirectly confirmed during an endoscopic submucosal dissection (ESD). Regarding the pathogenesis of GHIP, a submucosal hamartomatous change may occur prior to the growth of hypertrophic portions. An en bloc resection using ESD is recommended for treatment.

Multifocal Adenocarcinomas Arising within a Gastric Inverted Hyperplastic Polyp

We present herein the occurrence of multifocal adenocarcinomas with a minute signet ring cell carcinoma that arose within a gastric inverted hyperplastic polyp (IHP) in a 40-year-old woman. Endoscopic ultrasonography demonstrated a heterogeneous hypoechoic mass in the third layer of the gastric wall. The endoscopic submucosal dissection specimen measuring 3.5×3.2×1.8 cm was a well-circumscribed protruding lesion that had a slit-shaped cavity. Histologically, the lesion consisted mainly of endophytic proliferation of hyperplastic columnar cells resembling normal foveolar epithelium. In addition, six foci of adenocarcinomas and a minute focus of signet ring cell carcinoma were randomly distributed in the superficial and deep regions. The adenocarcinoma was gradually transitioning from dysplasia, while the signet ring cell carcinoma was surrounded by hyperplastic foveolar epithelium. This is the first report of a gastric IHP with multifocal intramucosal adenocarcinomas and a signet ring cell carcinoma, and endoscopic submucosal dissection is used to completely resect it.

Myoepithelial hamartoma of the stomach simulating a gastric carcinoma. A case report

Myoepithelial hamartoma is a very rare submucosal tumor of the stomach. Magnus-Alsleben first described 5 cases of this tumor in 1903. More recently (1993) Vandelli et al. published a review of the literature comprising only 33 cases. Histologically, the tumor is characterized by hypertrophic smooth muscle bands surrounding diverse epithelial elements that can be arranged in different ways: as a simple glandular structure, Brunner's gland, pancreatic ducts and occasionally pancreatic acinus. We report a case of myoepithelial hamartoma of the stomach simulating a gastric carcinoma.

Adenocarcinoma arising in gastric inverted hyperplastic polyp: a case report and review of the literature

A 54-year-old man, found to have a submucosal tumor in the stomach by double contrast roentgenography, endoscopy, and endoscopic ultrasonography, underwent a laparoscopic partial gastrectomy. The pathological examination revealed that the lesion, measuring 45 mm x 35 mm, was an inverted hyperplastic polyp (IHP) located in the submucosal layer and consisting mostly of columnar cells resembling foveolar epithelium and pyloric gland cells. Notably, adenocarcinoma with adjacent dysplasia was observed in the submucosal glands. Transition from hyperplasia to dysplasia and from dysplasia to adenocarcinoma was noted. The adenocarcinoma component was intensely and diffusely positive for p53 overexpression, while the dysplasia component showed only weak and focal positivity, suggesting a role of p53 mutation in the dysplasia-carcinoma sequence. Gastric IHP is very rare, and only 31 cases (in 29 patients) have been reported. Five of these IHPs coexisted with gastric adenocarcinomas, which had all developed separately from the IHP lesions. Therefore, this is the first case of adenocarcinoma arising within gastric IHP itself.

Gastric inverted hyperplastic polyp. Report of four cases and relation to gastritis cystica profunda

Gastric inverted hyperplastic polyp (IHP) is a rare type of gastric polyp, and is characterized by downward growth of the hyperplastic mucosal components into the submucosa. To the best ofour knowledge, 16 gastric IHP cases have been described in the English literature, but the pathogenesis has not been established. We report the clinical and pathological findings of four gastric IHP cases. The lesions were mainly composed of hyperplastic foveolar-type glands with focal cystic dilatation. Pyloric type glands, endocrine cells, acinic cell metaplasia, and smooth muscle bundles were also seen as components of the polyp. Two cases (cases 1 and 4) coexisted with multifocal gastritis cystica profunda (GCP) and gastric adenocarcinoma. Case 4 furthermore exhibited an intermediate form between IHP and GCP. We suggest that IHP may be GCP associated with exaggeratedly hyperplastic and metaplastic changes. In case 4, the coexisting gastric carcinoma was mainly located in the submucosa, whilst the mucosal component was minimal. Five out of twenty reported gastric IHP cases, including our cases, coexisted with gastric adenocarcinoma. These facts would lead us to further investigate the relation between gastric IHP and carcinoma.