Endocrine neoplasm of the stomach. Study of thirteen cases

A Thirteen patients with primary endocrine neoplasm of the stomach were studied for 20 years. Six patients were male and 7 female with an age range of 33 to 77, mean age 57 years. Nine cases corresponded to well differentiated carcinoids and four to neuroendocrine carcinomas. Of the former, three were sporadic and six were associated with atrophic gastritis. These two forms of neoplasm showed important differences: those associated with atrophic gastritis had hypergastrinemia, all of the multiple small tumors confined to the corpus and fundus were well differentiated carcinoids associated with intestinal metaplasia and G cell hyperplasia in antrum and ECL cell hyperplasia in corpus and fundus. Tumors were clinically benign, with an excellent prognosis. All patients are currently alive with no evidence of neoplasm. In only one of these cases, antiparietal cell antibodies were documented; in three of them, extensive intestinal metaplasia probably due to Helicobacter pylori infection was found. In contrast, sporadic carcinoids were large isolated tumors originating in the antrum or corpus. Two patients died as a consequence of the neoplasm; all of them were moderately differentiated and in none of the cases we found evidence of endocrine hyperplasia. All were positive for generic endocrine markers and were focally positive to some of the specific hormone markers. Al four neuroendocrine carcinomas had a clinical course similar to that of gastric adenocarcinomas and were poorly differentiated large tumors. We conclude that gastric carcinoids associated with atrophic gastritis have an excellent prognosis. On the other hand, neuroendocrine carcinomas have a very poor prognosis with fatal outcome of patients. Sporadic carcinoids have an intermediate prognosis.     

Gastric Carcinoids of Argyrophil ECL Cells

Histochemical and ultrastructural studies were carried out in four gastric carcinoids, two of which were associated with atrophic gastritis and pernicious anemia. All tumors showed intense argyrophilia and vesicular granules resembling those of endocrine enterochromaffinlike (ECL) cells in normal human gastric mucosa. Tumor cells were found to be unreactive to all the 18 available antiserums to gut hormones, including gastrin, somatostatin, glucagon, and pancreatic polypeptide. The tumors were interpreted as ECL cell argyrophil carcinoids with various degrees of differentiation and atypia.     

Gastric Carcinoids of Argyrophil ECL Cells

Histochemical and ultrastructural studies were carried out in four gastric carcinoids, two of which were associated with atrophic gastritis and pernicious anemia. All tumors showed intense argyrophilia and vesicular granules resembling those of endocrine enterochromaffinlike (ECL) cells in normal human gastric mucosa. Tumor cells were found to be unreactive to all the 18 available antiserums to gut hormones, including gastrin, somatostatin, glucagon, and pancreatic polypeptide. The tumors were interpreted as ECL cell argyrophil carcinoids with various degrees of differentiation and atypia.     

Ultrastructural characterization of fundic endocrine cell hyperplasia associated with atrophic gastritis and hypergastrinaemia

Summary Clinical and experimental evidence indicates that carcinoid tumours of the stomach fundic mucosa represent another example of hormone-dependent neoplasm, gastrin being the hormone involved in tumour induction. In this context hyperplasia of fundic endocrine cells associated with chronic atrophic gastritis (CAG) and hypergastrinaemia is regarded as the most frequent preneoplastic lesion. However, the cell type involved in this hyperplasia has not been clarified. To elucidate this problem fundic endocrine cells were characterized ultrastructurally in 9 patients from which endoscopic gastric biopsies were obtained. ECL cells were the most frequent cell type in 8 cases, in 4 of which they were more numerous than all other cell types taken together. D₁ cells were the most frequent type in one case while they were inconspicuous in the other cases. P cells were found with a frequency in each case intermediate between that of ECL cells and that of D₁ cells. These results indicate that fundic endocrine cell hyperplasia occurring in hypergastrinaemic CAG is in most cases cytologically similar to that found in other hypergastrinemic conditions, in which the gastrin-dependent ECL cells were already found to prevail. They also explain why fundic carcinoids arising in CAG are mostly composed of ECL cells. The relation between ECL, D₁ and P cells, if any, remains obscure.Abbreviations EC enterochromaffin cells, producing 5-hydroxytryptamine - ECL enterochromaffin-like cells - D somatostatin producing cells - D₁ cells with small granules showing some characteristics of granules of D cells - P cells with small granules similar to those of pulmonary (P) endocrine cells - X gastric endocrine cells with large, dense granules. Unless specified, the secretory product of these cells is unknown Supported by grants from the Italian Ministry of Public Education and from the A.I.R.C. (Associazione Italiana per la Ricerca sul Cancro)     

Physiopathology of Helicobacter pylori infections

Helicobacter pylori (H.p.) causes active chronic gastritis in nearly all infected patients. Cytotoxic factors elaborated by H.p. as well as autoimmune cell damage from the abundant inflammatory response contribute to gastric epithelial cell injury. Antrum gastritis increases gastrin release. The impact of H.p.-infection on gastric acid physiology is complex and usually results in increased gastric acid secretion in duodenal ulcer patients and diminished acid output in patients with gastric cancer. Multiple clinical outcomes including asymptomatic gastritis, duodenal ulcer, gastric ulcer, gastric carcinoma and gastric MALT lymphoma are associated with H.p.-infection. Differences in disease manifestation seem to result from a complex interaction of bacterial virulence, host factors as well as environmental factors. The acid-secretory ability of the infected individual seems to be the main variable determining outcome: Patients with high acid production typically develop antrum-predominant gastritis and are at an increased risk for duodenal ulcer. In contrast patients with low gastric acid secretion frequently develop pangastritis, which may progress to chronic atrophic gastritis and carcinoma.     

Ghrelin expression in hyperplastic and neoplastic proliferations of the enterochromaffin-like (ECL) cells

Ghrelin, a recently discovered peptide isolated from the gastric corpus mucosa, is believed to be important in the regulation of growth hormone secretion and has been shown to increase appetite and food intake as well. It may also have other gastrointestinal and cardiac functions. Because a cell of origin for ghrelin has not been convincingly identified in the gastric mucosa thus far, we studied the immunohistochemical expression of ghrelin in proliferative lesions of the enterochromaffin-like (ECL) cells—a cell that is not only exclusively confined to the gastric corpus mucosa but is its dominant endocrine cell type as well. Formalin-fixed, paraffin embedded tissues from three cases of gastric ECL cell hyperplasia and five ECL carcinoids (three with coexisting foci of diffuse, linear, and micronodular hyperplasia) were immunohistochemically stained for ghrelin, using a commercially available antibody. The Sevier-Munger stain for ECL cells and immunohistochemical stains for chromogranin, gastrin, serotonin, somatostatin, and vesicular monoamine transporter-2 (VMAT-2) were performed on parallel sections for correlation with the ghrelin staining results. All ECL cell carcinoids and hyperplastic lesions were positive for both the Sevier-Munger and the immunohistochemical stains for chromogranin and VMAT-2. Immunoreactivity for ghrelin was seen in 4/5 ECL carcinoids, all cases of ECL cell hyperplasia, as well as in all areas with linear and micronodular hyperplasia adjacent to the ECL cell carcinoids. In each instance, such staining was confined to the Sevier-Munger, and VMAT-2 positive cells only. Our findings indicate that the ECL cells are either the ghrelin-producing cells of the gastric mucosa or acquire the capability to synthesize ghrelin during proliferative states encompassing the entire hyperplasia to neoplasia spectrum. In view of the orexigenic and other known actions of ghrelin, the functional and/or biologic significance of ghrelin production in such ECL cell proliferations needs to be investigated further.     

Gastric neuroendocrine carcinoma associated with atrophic gastritis in the norwegian lundehund

In humans and rodents the association between atrophic gastritis, hypergastrinemia and gastric neoplasia is well-documented. Gastric tumours are rare in dogs, but the Norwegian Lundehund (puffin dog) appears predisposed to the development of gastric neoplasia associated with chronic atrophic gastritis. The present study describes 8 Lundehunds with gastric neoplasia. Seven of these animals had concurrent chronic atrophic gastritis characterized by reduction in parietal cells and hyperplasia of neuroendocrine cells. Four of the tumours displayed neuroendocrine (enterochromaffin-like cell; ECL) differentiation, suggesting that hypergastrinemia secondary to fundic atrophy may be important in carcinogenesis. The Norwegian Lundehund may therefore represent a further animal model for the study of the role of gastrin in the induction of gastric neoplasia.     

Endocrine Precursor Lesions of Gastroenteropancreatic Neuroendocrine Tumors

This review focuses on precursor lesions of gastrointestinal and pancreatic neuroendocrine tumors (GEP-NETs). There are three conditions that are associated with hyperplastic changes in endocrine cells preceding GEP-NETs: autoimmune chronic atrophic gastritis or multiple endocrine neoplasia type 1 (MEN1) with gastric enterochromaffin-like (ECL) cell hyperplasia; MEN1 with gastrin and somatostatin cell hyperplasia in the duodenum and glucagon cell hyperplasia in the islets of the pancreas; and inflammatory bowel disease with endocrine cell hyperplasia in the colon. In gastric ECL cell hyperplasia, it is assumed that hypergastrinemia promotes the growth of the ECL cells of the corpus mucosa and leads to hyperplasia and neoplasia. In the duodenum and the pancreas, the MEN1-associated germline mutation of the menin gene obviously causes hyperplasia of the gastrin and somatostatin cells (duodenum) and the glucagon cells (pancreas), resulting in multifocal development of tumors. These tumors show allelic deletion of the MEN1 gene, whereas the precursor lesions retain their heterozygosity. The endocrine cell hyperplasia in the colon described in inflammatory bowel disease has neither a genetic nor a definite hormonal background.     

G‐cell hyperplasia of the stomach induces ECL‐cell proliferation in the pyloric glands in a paracrinal manner

An inhibitory mechanism toward gastrin hypersecretion is significantly different between G‐cell hyperplasia and gastrinoma despite the common clinical manifestations; hypergastrinemia and its related persistent gastric ulcers. We recenlty studied the G‐cell, d ‐cell and ECL‐cell density in a case of G‐cell hyperplasia. The 70‐year‐old patient has been treated for persistent gastric ulcers with a markedly increased plasma gastrin (5600 pg/mL). The stomach was surgically resected because of the obstruction associated with ulcer scars. The number of G‐cells in the pyloric glands was quantified on the surgical specimens and G‐cell hyperplasia was histolopathologically identified. Immunostainig of histidine decarboxylate revealed the presence of ECL‐cell hyperplasia in the pyloric glands and its density was significantly and positively correlated with G‐cell density. Somatostatin immunoreactive cells (d ‐cells) increased in their number in the oxyntic glands. These results all indicated that hypersecretion of gastrin in G‐cell hyperplasia could induce ECL‐cell proliferation in a paracrinal manner. In addition, relatively non‐prominent endocrinological features in the G‐cell hyperplasia compared to gastrinoma could be also related to the paracrinal somatostatin inhibitory effects upon ECL‐cells in the pyloric glands.     

Omeprazole: its influence on gastric acid secretion, gastrin and ECL cells

The H+,K+-ATPase inhibitor omeprazole is a highly effective gastric antisecretory agent, both in animals and man, with a long duration of action. These properties are shared by a number of recently described histamine H2-receptor antagonists. In life-long oncogenicity studies of these H2-receptor antagonists, as well as with the H+,K+-ATPase inhibitor omeprazole, gastric enterochromaffin-like cell (ECL cell) hyperplasia and carcinoids have been found. The purpose of this paper is to summarize available evidence for the "Gastrin Hypothesis" to explain the development of ECL-cell hyperplasia. The hypothesis may be outlined as follows: 1) Inhibition of gastric acid secretion leads to elevated antral pH and, secondarily, to release of gastrin from the antral gastrin cells into the blood stream. 2) Gastrin causes both general hypertrophy of the oxyntic mucosa and hyperplasia of the ECL cells in the oxyntic mucosa. That this sequence of events occurs not only with omeprazole but also with other effective gastric antisecretory agents has been verified in the rat by giving the H2-receptor antagonist ranitidine as a continuous infusion. Ranitidine caused a hypergastrinemia of a similar magnitude as that seen after omeprazole, provided that the acid secretion was inhibited to a similar degree. At similar gastrin levels, ECL-cell hyperplasia of the same magnitude developed during both ranitidine and omeprazole treatment. Antrectomy prevented the development of ECL-cell hyperplasia during omeprazole treatment, indicating that the hyperplasia was not due to the drug treatment per se, but rather to the hypergastrinemia. Both the hypergastrinemia and the ECL-cell hyperplasia were found to be reversible.(ABSTRACT TRUNCATED AT 250 WORDS)     

The origin of subdural neomembranes. I. Fine structure of the dura-arachnoid interface in man.

A patient with atrophic gastritis and excessively raised serum gastrin concentrations (4000 to 5000 pg/ml) was found to have multiple polypous tumors of the gastric corpus mucosa. Following gastrectomy, serum gastrin concentrations decreased to undetectable levels. The tumors consisted of a mixed population of endocrine cells. The majority of tumor cells were of the ECL type, but, in addition, enterochromaffin cells of various subtypes as well as agranular cells were found. The tumors were locally invasive and invaded the walls of submucosal blood vessels. The surrounding mucosa showed a severe atrophic gastritis with intestinalization and contained numerous goblet cells, enterochromaffin cells, and cholecystokinin cells. Cholecystokinin cells do not occur in the normal oxyntic mucosa. Hence, the observation of this cell type in intestinalized gastric epithelium suggests that "intestinalization also is associated with changes in endocrine cell populations. Gastrin has been shown to affect the function of the ECL cells. Indications for a trophic action of gastrin on these cells have been obtained. It is discussed whether greatly raised serum gastrin levels in patients with atrophic gastritis may be associated with increased risks for the development of certain types of gastric tumors.     

Malignant Enterochromaffinlike Cell Carcinoid of the Gastric Stump: An Ultrastructural Study

A metastasizing carcinoid of the gastric stump found 25 years after Billroth II gastric resection for duodenal ulcer is described. Electron microscopy and optical endocrine cell staining proved the tumor to be composed of enterochromaffinlike (ECL) cells. This unusual combination further shows that, at variance with most of these tumors, ECL cell carcinoids may develop also in a condition excluding a trophic effect of gastrin. This case emphasizes the malignant behavior of gastrin-independent ECL cell tumors.     

Neuroendocrine differentiation in gastric adenocarcinomas associated with severe hypergastrinemia and/or pernicious anemia

Patients with hypergastrinemia secondary to achlorhydria have an increased risk of developing ECL cell carcinoids and gastric adenocarcinomas. Hypergastrinemia is central in the pathogenesis of ECL cell carcinoids, but the link between gastrin and gastric carcinomas is controversial. During neoplastic transformation ECL cells may, however, lose many of their neuroendocrine characteristics, making them difficult to recognise as neuroendocrine with conventional immunohistochemical techniques. Neuroendocrine differentiation was therefore examined in eight gastric adenocarcinomas found in seven patients with severe hypergastrinemia and/or pernicious anemia using a monoclonal antibody towards chromogranin A and immunohistochemistry without and with a sensitive signal amplification technique. The Sevier-Munger method was used as a more specific marker of ECL cells. Seven of the carcinomas contained scattered neuroendocrine tumour cells. When using signal amplification, an increase in the number of immunoreactive neoplastic cells was seen. In many tumours, clusters or confluent sheets of such cells were disclosed, suggesting a neuroendocrine and ECL cell origin. These tumours may therefore be ECL cell carcinomas and hypergastrinemia may thus be involved in the tumourigenesis.     

Gastric polyposis caused by multiple carcinoids and early carcinoma.

A case of gastric polyposis caused by multiple carcinoids with concurrent gastric carcinoma is reported in a 70 year old woman with severe atrophic gastritis and intestinal metaplasia. On microscopic examination, the carcinoids and gastric carcinoma arose separately thus representing "double primaries". Long-standing hypergastrinaemia probably plays a causative role in the development of carcinoma and carcinoids. Carcinoid tumours, although of low malignant potential, may be important as indicators of other unrelated high risk malignancies. Patients with carcinoids should be followed closely, especially as the incidence of these tumours seems to be on the increase.     

幽门螺杆菌诱导蒙古沙鼠胃类癌发生的实验研究

目的 探讨幽门螺杆菌(Hp)感染在蒙古沙鼠胃类癌发生中的作用及Hp去除后对胃类癌发生的影响.方法 100只蒙古沙鼠分成7组,A、B为空白对照组,C、D、E、F、G为Hp感染组,其中F、G组Hp感染后再去除.结果 空白对照组(A、B组)未见ECL细胞增生/异型增生及类癌形成,Hp感染后(C、D、E组),血清抗Hp IgG抗体、胃泌素水平均明显增高(P<0.01),ECL细胞增生/异型增生及类癌发生率分别为27.8%(5/18)、31.2%(5/16)、58.3%(14/24)和16.7%(3/18)、31.2%(5/16)、62.5%(15/24),均明显高于对照组(P<0.01),随着Hp感染时间的延长,ECL病变面积明显增加(P<0.01);Hp去除后,血清抗Hp ISG抗体、胃泌素水平明显降低,ECL细胞增生/异型增生及类癌的发生率降低,分别为25.0%(4/16)、15.4%(2/13)和37.5%(6/16)、23.1%(3/13).早期阶段去除Hp(G组),ECL病变发生率及类癌的面积明显低于非去除组(E组)(P<0.001).血清抗Hp ISG抗体与胃泌素水平及胃泌素水平与胃类癌的发生呈正相关(P<0.001).结论 Hp感染在蒙古沙鼠胃类癌发生中起重要作用,去除Hp可有效预防蒙古沙鼠胃类癌的发生.     

Topical Review

Transepithelial transducing cells, particularly the gastrin (G) cell, co-ordinate gastric acid secretion with the arrival of food in the stomach. Recent work suggests that multiple active products are generated from the gastrin precursor, and that there are multiple control points in gastrin biosynthesis. Biosynthetic precursors and intermediates (progastrin and Gly-gastrins) are putative growth factors; their products, the amidated gastrins, regulate epithelial cell proliferation, the differentiation of acid-producing parietal cells and histamine-secreting enterochromaffin-like (ECL) cells, and the expression of genes associated with histamine synthesis and storage in ECL cells, as well as acutely stimulating acid secretion. Gastrin also stimulates the production of members of the epidermal growth factor (EGF) family, which in turn inhibit parietal cell function but stimulate the growth of surface epithelial cells. Plasma gastrin concentrations are elevated in subjects with Helicobacter pylori , who are known to have increased risk of duodenal ulcer disease and gastric cancer. Studies of the physiology of gastrin may therefore contribute to an understanding of the mechanisms relevant to major upper gastrointestinal tract disease.     

PGⅠ、PGⅡ、G 17和Hp IgG抗体筛查慢性萎缩性胃炎和胃癌的价值

分析胃蛋白酶Ⅰ（PGⅠ）、胃蛋白酶Ⅱ（PGⅡ）、胃泌素 17（G 17）和幽门螺杆菌（Hp IgG）抗体筛查对慢性萎缩性胃炎和胃癌的诊断价值。方法：以2014年5月至2015年5月胃部不适来我院就诊的90例患者为研究对象,根据病理诊断结果分为正常对照组（包括慢性非萎缩性胃炎）、慢性萎缩性胃炎组和胃癌组,每组各30例,比较三组患者PGⅠ、PGⅡ、G 17水平及Hp IgG抗体阳性检出率。结果：胃癌组患者的PGⅠ、PGⅡ水平低于对照组和慢性萎缩性胃炎组,且慢性萎缩性胃炎组患者上述指标低于对照组;胃癌组G 17水平高于慢性萎缩性胃炎组和对照组,而慢性萎缩性胃炎组和对照组无明显差异;三组间Hp IgG抗体阳性率有明显差别,胃癌组显著高于对照组和慢性萎缩性胃炎组;Hp感染患者的PGⅠ和PGⅡ水平低于未感染Hp者,而G 17水平高于未感染Hp者;胃癌患者的PGⅠ、PGⅡ水平与年龄、病理分期和转移显著负相关,与分化程度显著正相关,而G 17水平及Hp IgG抗体阳性率与年龄、病理分期和转移显著正相关,而与分化程度显著负相关。结论： PGⅠ、PGⅡ和Hp IgG抗体筛查对慢性萎缩性胃炎和胃癌均有很好的诊断价值,而对胃癌的诊断价值更好,G17对胃癌的诊断价值远远好于慢性萎缩性胃炎;且PGⅠ、PGⅡ、G17水平及Hp IgG抗体阳性检出率与胃癌患者的临床病理特征密切相关。     

Pattern of gastric endocrine cells in microcarcinoidosis — an immunohistochemical study of 14 gastric biopsies

A total of 14 gastric biopsy specimens from patients with microcarcinoidosis were analysed by immunohistochemical methods to evaluate the pattern of endocrine cell hyperplasia and dysplasia. All the patients had type A gastritis (autoimmune gastritis). Nonantral proliferations of gastric endocrine cells were classifed according to Solcia et al. All 14 cases had hyperplasia and 13 (92.9%) of them, dysplasia of gastric endocrine cells; 9 (64.3%) of the 14 were found to have showed a coexisting invasive gastric carcinoid at the time of diagnosis of microcarcinoidosis. The patients with invasive carcinoids had higher degrees and more complex forms of endocrine dysplasia (precarcinoid lesions). The average size of the foci of the microcarcinoidosis in gastric biopsies was 0.14±0.09 cm in the patients without invasive carcinoid, as against to 0.5±0.24 cm in the group of patients with associated invasive carcinoid. Microcarcinoid gastric biopsies about 0.5 cm in size, are suggestive of adjacent invasive carcinoid. However, even frankly invasive ECL carcinoids seem to be clinically less dangerous than was thought until recently.     

Mechanism of hypergastrinaemia after nephrectomy in the rat

Bilateral nephrectomy in the rat is followed by hypergastrinaemia and by activation of gastric histidine decarboxylase. The enzyme activity is thought to reflect the concentration of circulating gastrin. While there is general agreement that post-nephrectomy hypergastrinaemia is primarily the result of loss of renal elimination of gastrin, it remained to be determined whether gastrin secretion could be stimulated in the hypergastrinaemic state and whether it contributed to the hypergastrinaemia. Histamine, but not pentagastrin, is known to evoke gastric acid secretion in the nephrectomized rat, and histamine, but not pentagastrin, was found to lower the serum gastrin level and the gastric histidine decarboxylase activity, indicating that after nephrectomy gastrin was still secreted and that the secretion could be suppressed by increased acid output. The importance of gastrin secretion for post-nephrectomy hypergastrinaemia was assessed further by investigating the effect of nephrectomy on the serum gastrin concentration in rats previously subjected to operations that had either reduced (e.g. antrectomy) or raised (e.g. antrum exclusion) the serum gastrin concentration. Post-nephrectomy serum gastrin levels co-varied with the levels before nephrectomy. Thus, the capacity to secrete gastrin was not abolished by nephrectomy. Finally, nephrectomy greatly affected the linear correlation between the serum gastrin concentration and the gastric histidine decarboxylase activity in a manner suggesting the operation of a gastrin-independent factor capable of activating the enzyme.     

Gastric function and histology in chronic renal failure.

Gastric function and histology were investigated in 24 patients with untreated chronic renal failure. At endoscopy nine patients had oesophagitis, 12 patients were considered to have gastritis, and the duodenum appeared inflamed in 20 patients. Endoscopic biopsies were taken at standard sites in the stomach and duodenum; gastritis was found in all patients, and 17 patients had duodenitis. Stimulated acid secretion was impaired in seven out of 20 patients and acid hypersecretion was found in a further two patients. Pepsin output correlated well with acid output in these patients. Fasting serum gastrin levels were elevated in 12 of the 19 patients tested. Patients with atrophic gastritis had low acid outputs and hypergastrinaemia, and when extensive gastritis was present, the patients tended to have more severe renal failure and hyposecretion of acid. Three patients were studied again after regular haemodialysis or renal transplantation and were found to show marked endoscopic and histological improvement.