Clinicopathological features and natural history of gastric hamartomatous polyps

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.

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.

Gastric smooth muscle hamartoma in a cat

An 11-year-old cat presented for evaluation of intermittent vomiting, constipation and hyporexia of 3 weeks duration. Ultrasonographic and endoscopic examination revealed a soft tissue mass adjacent to the lower gastro-esophageal sphincter. Surgical excision of the mass was successfully performed resulting in a resolution of clinical signs. Histologically the mass was consistent with a smooth muscle hamartoma. At follow-up 7 months after surgery, the cat remained free from clinical signs.

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.

Smooth Muscle Hamartoma of the Abomasum in a Calf

This report describes a case of smooth muscle hamartoma of the abomasum in a 6-month-old steer humanely killed because of severe pneumonia. At necropsy, marked thickening of the abomasal wall in the area of the pylorus was found. On cut section, the thickness of the submucosal layer, extending from the submucosa to the muscularis propria, was seen to be increased to 3 cm. The upper (i.e., nearest to the gut lumen) half of the sectioned thickening was composed mainly of adipose-like tissue and the lower half mainly of muscle-like tissue. Histologically, the submucosal layer was composed of fibroadipose tissue, within which were embedded, to varying degrees, numerous well-defined, haphazardly oriented, thin to thick bundles of smooth muscle fibres. This appears to be the first report of smooth muscle hamartoma of the stomach or abomasum in animals, including man.

Gastric fundic gland polyps: a morphological study including mucin histochemistry, stereometry, and MIB-1 immunohistochemistry

Fundic gland polyps are benign lesions, composed of a disorderly arrangement of normal gastric corpus cell types, that occur in a large proportion of patients with familial adenomatous polyposis (FAP) but also develop sporadically in non-FAP patients as well. In this study, the authors evaluated and compared the endoscopic, histological, mucin histochemical, and microscopic stereologic features of 77 fundic gland polyps (FGPs) (15 FAP; 62 non-FAP) to determine if FAP-associated and sporadic lesions are histologically distinct. The authors also analyzed the distribution of mitotically active cells and smooth muscle cells in these lesions using MIB-1 and smooth muscle alpha-actin immunohistochemistry in an effort to determine the pathogenesis of these lesions. The results show that, compared with non-FAP cases, FAP patients with FGPs have a lower male-to-female ratio, a younger mean age at diagnosis, and a higher proportion of cases with multiple polyps. However, no differences were detected between FAP and non-FAP-associated FGPs with respect to any endoscopic, morphological, mucin histochemical, or stereometric features. Eighty-six percent of FGPs showed an increase in smooth muscle content, often in a pericystic distribution. MIB-1-positive proliferative cells were observed not only in the foveolar stem cell region, as expected, but also in the epithelium lining the microcysts and in the gland buds located directly adjacent to the microcysts. The authors conclude that FAP and non-FAP-associated FGPs are histologically identical, and propose that proliferation and subsequent differentiation of aberrantly located proliferative cells in these lesions may explain the histogenesis of FGPs.

Clinical evaluation of gastric fundic gland polyps without familial polyposis coli

BACKGROUND

Assessments were made of 63 cases of fundic gland polyposis (FGP) unassociated with adenomatosis coli. These cases were evaluated by radiological examination over 2 years follow-up. All polyps were pathologically confirmed by endoscopic biopsies.

METHODS

Most cases were asymptomatic when diagnosed during mass radiological surveys of the upper gastrointestinal tract. The majority of patients ranged in age from 40-60 years, and the polyps numbered fewer than 20 in 55 cases (87.3%). Polyps were detected in the fundic glands using the congo red test and by biopsies.

RESULTS

All serum gastrin values were within the normal range. During the course of this study, the polyps of 13 cases (20.6%) increased and those of three cases (4.8%) decreased or resolved completely.

CONCLUSION

From these findings it is considered that FGP are observed in stomachs with less atrophy, and that polyps follow courses in which they increase, decrease, disappear, along with atrophy.

Precursors of gastric carcinoma: a critical review with a brief description of early (curable) gastric cancer

Gastric adenocarcinoma is among the most common malignancies worldwide. Its etiopathogenesis is complex and, as yet, incompletely understood; however, diet, infection with Helicobacter pylori, and genetic factors are involved. It may be classified into two main types, intestinal and diffuse. The intestinal type has decreased in incidence, whereas the diffuse tumors as well as those confined to the cardia are increasing. Numerous conditions, such as gastritis, gastric atrophy, and intestinal metaplasia (IM), are associated with intestinal type gastric cancer in retrospective studies, but only epithelial dysplasia has a positive predictive value for malignancy. These precursor conditions and lesions are analyzed for their clinicopathological significance in this review, which concludes with a brief summary of curable (early) forms of gastric cancer.

Report of three gastric tumors in children

The literature concerning gastric tumors in children is mainly limited to case studies. The authors reviewed 1,403 histological reports of pediatric gastric pathology (covering 10 years) at their institution. There were three gastric tumors of benign histology and no malignant tumors. The first patient was a 9 1/2-year-old boy who presented with several months of symptomatic, pH-probe-confirmed gastroesophageal reflux. He underwent placement of a Toupet antireflux valve. During laparotomy, a submucosal mass was discovered incidentally, on the greater curvature of the stomach. The mass was excised. Pathological examination showed heterotopic pancreas. The second patient, a 15-month-old girl, presented with a short period of vomiting. Results of an upper gastrointestinal series showed gastric outlet obstruction. She underwent laparotomy and was found to have an intussusception of a gastric polyp into the proximal jejunum, and an associated malrotation. Ladd's procedure, gastroduoduodenostomy with reduction of the intussuscepted polyp, and excision of the polyp were performed. Histological examination of the tumor showed hamartoma with hyperplastic elements. The tumor was benign but was regarded as difficult to classify. The third patient, a 6-year-old boy, presented with microcytic anemia. Endoscopy showed multiple friable bleeding gastric masses. He underwent laparotomy, with partial gastrectomy and pyloroplasty. Histological examination showed the tumor to be plasma cell granuloma. The tumor recurred, and the patient required subsequent operative procedures. The authors confirm that gastric tumors in children are rare. Although the tumor histology may be benign, excision of the tumor may require major operative resection.