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PubMedDate not supplied

Myeloid metaplasia of the central nervous system in patients with myelofibrosis and agnogenic myeloid metaplasia. Report of 3 cases and review of the literature.

Foci of meningeal myeloid metaplasia were found in 3 of 11 consecutive autopsied patients with myelofibrosis and agnogenic myeloid metaplasia. The clinical and pathological findings in an additional seven published patients with agnogenic myeloid metaplasia who developed neurological manifestations due to pressue of hemopoietic tumors in the central nervous system are reviewed.

Aged↗

PubMed1992

Endometrial metaplasia associated with endometrial carcinoma.

OBJECTIVE: To clarify the relationship of metaplasia to endometrial carcinoma. METHODS: Between 1984-1990, 73 cases of stage I-II endometrial carcinoma treated initially by hysterectomy were reviewed histologically. The metaplasias were classified as squamous, syncytial papillary, ciliated-cell, eosinophilic, mucinous, clear-cell, or hobnail. We assessed the histologic type and grade of the carcinoma, depth of myometrial invasion, presence or absence of lymph-vascular space invasion, and presence or absence of lymph node metastases. RESULTS: Forty of 73 patients (55%) had one or more areas of metaplasia in the endometrium adjacent to the carcinoma. Ciliated-cell metaplasia (28 of 73; 38%) was the most common type encountered. Women with both endometrial carcinoma and metaplasia were significantly younger than those with carcinoma without metaplasia (P < .05). Compared with carcinomas without metaplasia, those with metaplasia were well differentiated (P < .01) and lacked myometrial invasion (P < .01) and pelvic lymph node metastases (P < .05). The presence of metaplasia was also significantly correlated with the presence of endometrial hyperplasia (P < .01). CONCLUSION: In endometrial carcinomas, the presence of endometrial metaplasia suggests a favorable prognosis.

Adult↗

PubMed1978

Special features of intestinal metaplasia and its relation to early gastric carcinoma in man: observation by a method in which leucine aminopeptidase activity is used.

The degree of intestinal metaplasia and its macroscopic distribution in gastric mucosa were examined by a new method in which leucine aminopeptidase (LAP) activity is used to investigate the relationship between intestinal metaplasia and gastric carcinoma. Since LAP is a specific enzyme of intestinal metaplasia, the area showing positive reaction for this enzyme corresponds strictly with the zone of intestinal metaplasia examined microscopically. Almost all metaplasia was demonstrated by this method. This method was used to examine 40 human gastric carcinomas confined to the mucosa. Gastric mucosa containing differentiated tubular-type carcinoma (60%) was associated with a high degree of metaplasia in comparison with the low degree of metaplasia in poorly differentiated carcinoma (40%). Differentiated tubular-type carcinoma was closely related to intestinal metaplasia. However, all carcinomas arising from the mucosa without intestinal metaplasia (18%) were poorly differentiated. Therefore, gastric carcinomas occurring in Japanese patients are frequently and closely related to intestinal metaplasias.

Alkaline Phosphatase↗

PubMed1975

[Morphogenesis and significance of epithelial metaplasia in the human prostate gland. An electron-microscopic study (author's transl)].

Electron-microscopic studies were done to point out the morphogenesis of transitional and squamous epithelial metaplasia in the human prostate gland. The basis of epithelial metaplasia is a multi-layered proliferation of the basal cells and subsequent divergent differentiation. Transitional metaplasia can be viewed under the light microscope; the electron microscope on the other hand does not show all structural features of the transitional epithelium, such as: The cover cells of the metaplastic epithelium, which do not reach the basement membrane; the surface cells, which are always mononuclear and show signs of beginning adenoid differentiation. Extreme twisting of the lateral cell membranes as a morphological equivalent of deformability was not observed. Squamous epithelial metaplasia, contrary to transitional epithelial metaplasia, shows the criterions true characteristics of squamous epithelium at both the light and electron microscopic levels: The metaplastic cells have an abundant cytoplasm containing the characteristic structures with numerous tonofibrils and broad desmosomes. Microvilli-like processes of the cytoplasm project into the lacunar interfacial canals. In addition aggregates of glycogen granules and deposits of osmiophilic material can be seen, representing the first step of keratinization. Epithelial metaplasias in the prostate occur not only in the central area near the urethra, but also in the peripheral ducts and glandular acini. An estrogen-androgen imbalance is suggested to be an essential factor in the etiology of prostatic epithelial metaplasia. A reversibility of squamous epithelial metaplasia is unlikely. To our knowledge, the epithelial metaplasias in the prostate do not represent a precancerous lesion.

Basement Membrane↗

PubMed1977

Gastric gland metaplasia in the small and large intestine.

Fifty-six surgical specimens with various ulcerative intestinal disorders were microscopically investigated for evidence of gastric gland metaplasia. Thiry-one specimens (55-4%) showed pyloric gland metaplasia. Among the 31 patients with pyloric gland metaplasia, five showed true gastric metaplasia, consisting of parietal cells, chief cells, and mucous neck cells. The percentage of true gastric metaplasia among pyloric gland metaplasia was as high as 16%, an overall frequency of 9% among various ulcerative intestinal disorders. The mechanism of pyloric gland metaplasia and true gastric metaplasia is not understood, but may occur secondary to submucosal response to ulcer healing and subsequent alteration of the intraluminal condition in the intestine.

Adolescent↗

PubMedDate not supplied

Gastric intestinal metaplasia in ethnic groups in the southwestern United States.

The incidence of gastric cancer has declined dramatically in the United States during this century. However, the incidence of gastric cancer among Hispanics, Blacks, and Native Americans remains 2-3-fold higher than among Whites in this country. Populations with an increased risk of gastric cancer have predominantly the "intestinal" type of gastric cancer, and intestinal metaplasia is regarded as a histological precursor lesion of this type of gastric cancer. We sought to establish the prevalence of intestinal metaplasia, identify associated epidemiological factors, and improve detection of this lesion in a patient population undergoing clinically indicated endoscopy in the Southwestern United States. Among the 440 patients studied, we observed an overall crude prevalence of intestinal metaplasia of 19%. However, the crude prevalence among Hispanics and Blacks was found to be markedly higher than among non-Hispanic Whites (50% versus 13%). Two biopsy protocols (two biopsies versus four biopsies) were used during this study, with a significantly higher rate of intestinal metaplasia detection under the four-biopsy protocol. Adjusting for protocol, we found that age and ethnicity were significantly and independently associated with the prevalence of intestinal metaplasia. The odds of intestinal metaplasia diagnosis was significantly higher in Hispanics compared to non-Hispanic Whites (P < 0.001), and the prevalence of intestinal metaplasia increased with advancing age (P = 0.01). The presence of Helicobacter pylori was also significantly associated with the presence of intestinal metaplasia (P = 0.02), although the direction of the association differed between Hispanics and non-Hispanic Whites.

Adult↗

PubMed1979

Relation of intestinal metaplasia to the acid-secreting area.

The distribution of intestinal metaplasia in relation to the acid-secreting are was investigated in 66 patients not suffering from gastroduodenal diseases. Studies were made via the endoscopic Congo Red test in combination with the methylene blue staining method. In this test, the acid-secreting area is identified as a "discolored" area in which Congo Red turns from red to blue-black, and areas of intestinal metaplasia were observed as areas staining blue with methylen blue. A close relationship was found between the acid-secreting area and the distribution of intestinal metaplasia; in general, intestinal metaplasia tended to be more extensive and more frequent when the acid-secreting area was small. It was also found that intestinal metaplasia increased with age. However, even in patients who were over 40 years of age, intestinal metaplasia was seen in 12.5% only, if the acid-secreting area was large. Hence, it appears likely that development of intestinal metaplasia is more closely related to the acid-secreting function than to aging.

Adult↗

PubMed1976

Types of metaplasia in forty urothelial bladder carcinomas. A systematic histological investigation.

In a systematic study of bladders from consecutively cystectomized patients, 40 primary urinary bladder carcinomas were examined with regard to the type of differentiation. Metaplastic areas were found in 24 of the tumours. A positive reaction of keratin to Kreybergs stain was required for the definition squamous metaplasia. Squamous areas were found in 16 of the tumours. In 4 tumours there was, in addition to squamos metaplasia, glandular metaplasia which was defined as definite glandular tissue with dysplasia of the epithelium. In 4 tumours, glandular metaplasia was also present in addition to the urothelial carcinoma. In 18 cases, metaplastic changes were present in the luminal portion of the tumour from which the biopsy material and desquaminated material originated. The occurrence of metaplasia was related to the degree of differentiation of the urothelial part of the tumour. Metaplastic changes were most frequent in the poorly differentiated tumours. The biopsies obtained pre-operatively permitted of the diagnosis metaplasia being made in 15 cases, while the cytological material suggested metaplastic changes in 4 cases only. The biological function of metaplasia is unknow. The possibility that these areas will react differently to radiation and chemotherapy is present and the frequency of such changes would suggest that their importance should be studied by their registration as mixed forms as stated by WHO.

Adenocarcinoma↗

PubMed1978

Histochemical studies of mucosubstances in metaplastic epithelium of the stomach, with special reference to the development of intestinal metaplasia.

Processes in the development of intestinal metaplasia of the stomach were investigated from the morphological and histochemical approaches using light and electron microscopic techniques. The specimens taken from 38 gastric carcinomas and 15 gastric and/or duodenal ulcers were subjected to this study. Morphological appearances of the intestinal metaplasia observed in routine examination with hematoxylin and eosin staining was able to divided into complete and incomplete metaplasia by the light and electron microscope histochemical stainings of the mucosubstances. The columnar cells at the area of the incomplete metaplasia had both the properties of the intestinal epithelia and the gastric foveolar epithelia. The incomplete as well as the complete metaplasia arose from the generative cells at the isthmus of the gland. The generative cells, however, sometimes gradually transformed to produce the complete metaplastic cells. The two processes of the development of the intestinal metaplasia were proposed and discussed.

Duodenal Ulcer↗

PubMed1992

Site-dependent development of complete and incomplete intestinal metaplasia types in the human stomach.

The topographical distribution of complete and incomplete types of intestinal metaplasia in human stomach samples was investigated in order to elucidate their mutual histogenetic relationship and significance in carcinogenesis. Subgross stereomicroscopic examination of alcian blue and hematoxylin-stained gastric mucosae allowed clear distinction of complete and incomplete intestinal metaplasia types as white (with or without purple hue) and purple foci, respectively, against the background magenta areas of non-intestinalized mucosa. Intestinal metaplasias which developed in the fundic area were predominantly of the complete type whereas those of the antrum were a mixture of both with a distinct predilection for expression of the incomplete type. Although there was some variation among foci regarding the hue of white or purple, the color feature was principally homogeneous within each individual intestinal metaplasia focus. Thus phenotypic analysis indicated intestinal metaplasia expression to be clearly influenced by intragastric topography. The study did not provide any evidence that a shift from incomplete to complete type intestinal metaplasia may occur with time or that the incomplete type may be more intimately associated with development of well-differentiated carcinomas.

Adult↗

PubMed1992

Squamous cell metaplasia of the bladder urothelium. A retrospective study of 36 patients.

In a retrospective study of 28 women and eight men with squamous cell metaplasia in different parts of the bladder, including the trigone, no histopathological differences were observed among the regions. All the five (female) patients with parakeratosis had a concomitant invasive bladder tumour. Thirty-eight% of all the patients had a simultaneous neoplastic tumour. The metaplastic lesions were investigated for keratin in 13 patients, and all were positive. In seven out of eight patients, the urothelium adjacent to the squamous cell metaplasia was also positive for keratin, indicating a direct transformation of the urothelium to squamous cell epithelium. The metaplastic cells were investigated for oestrogen receptors in five men and five women, and all were negative, suggesting no relationship between estrogens and squamous cell metaplasia of the bladder. Squamous cell metaplasia in the bladder is not considered a premalignant condition. However, metaplasia and neoplastic tumours are often associated with chronic tissue damage, and the presence of metaplasia may give a warning of conditions that can also cause cancer.

Adult↗

PubMedDate not supplied

[The relationship between intestinal metaplasia and gastric carcinoma: a study of 722 biopsies].

Intestinal metaplasia has been shown by many investigators to be a premalignant state. Considering this fact, 722 gastric biopsies were studied, a 24% of association was found between gastric carcinoma and intestinal metaplasia and 27% of the cases with metaplasia were found in "apparently normal" or with benign stomach lesions. The group most affected was males over 61 years. Control endoscopy and biopsy was practiced in 17 patients with previously diagnosed intestinal metaplasia and in 11.7% gastric carcinoma with metaplasia was found. Therefore, it cannot be concluded that intestinal metaplasia is a premalignant condition, but its frequent association with gastric adenocarcinoma advises periodical examination by endoscopy in every patient over 40 years in which it is determined by biopsy.

Adenocarcinoma↗

PubMed1979

Gastrin and enteroglucagon cells in human antra, with special reference to intestinal metaplasia.

In a consecutive material consisting of 24 stomachs resected due to adenocarcinoma, intestinal metaplasia occurred in 21. Gastrin-producing cells (G-cells) were found to be distributed in a sporadic manner in antra with intestinal metaplasia. Not a single G-cell could be demonstrated in areas with metaplasia, while in the nonmetaplastic areas the distribution of the G-cells corresponded to that of the middle part of the mucosa. This means, that an error can occur when determining the quantity of G-cells, and can explain the previous controversial results regarding the density of G-cells. Enteroglucagon containing cells (GLI-cells) on the contrary were demonstrated in areas with intestinal metaplasia in antra of 19 of the stomachs showing intestinal metaplasia but never in the nonmetaplastic mucosa. This indicated that metaplasia also includes the endocrine cells. The identification of the G-cells and the GLI-cells was carried out by means of indirect immunoperoxidase technique combined with alcian blue pH 2,6-PAS staining.

Adenocarcinoma↗

PubMed1978

The respiratory epithelium. III. Histogenesis of epidermoid metaplasia and carcinoma in situ in the human.

The histogenesis of epidermoid metaplasia and carcinoma in situ was analyzed in human bronchial epithelium. The conclusion is that epidermoid metaplasia and carcinoma in situ can result from conversion of mucous cells. This implies the direct transformation of one type of fully differentiated cell to another. The study therefore emphasizes the differentiation potentialities of the mucous cells that can divide and undergo goblet cell hyperplasia and epidermoid metaplasia. Epidermoid metaplasia is a common reaction to injury in the bronchus. In our series of cases it was especially frequent in patients without neoplastic disease who had undergone intratracheal intubation or tracheostomy and who had been maintained on a respirator in the Shock Trauma Unit, University of Maryland. Future studies will be required to distinguish the difference, if any, between epidermoid metaplasia destined to become malignant carcinoma and that which is not. One difference noted in this study was the absence of overt cornification in epidermoid metaplasia in patients without neoplastic disease.

Bronchi↗

PubMed2024

The Protective Role of DDIT4 in Helicobacter pylori-induced Gastric Metaplasia Through Metabolic Regulation of Ferroptosis.

BACKGROUND & AIMS: Helicobacter pylori (H pylori) infection is a significant factor leading to gastric atrophy, metaplasia and cancer development. Here, we investigated the role of the stress response gene DDIT4 in the pathogenesis of H pylori infection. METHODS: Cell lines, transgenic mice, and human tissue samples were implemented. Proteomics were performed on Ddit4+/+ and Ddit4-/- mice infected with H pylori strain PMSS1. C57BL/6 mice were administered with tamoxifen to induce gastric metaplasia. Stomach tissues were analyzed for histopathologic features, reactive oxygen species, Fe2+, lipid peroxidation, expression of DDIT4, and ferroptosis-related proteins. RESULTS: DDIT4 expression was upregulated at 6 hours but significantly decreased at 24 hours in response to H pylori infection in gastric epithelial cells. Gastric DDIT4 were downregulated in INS-GAS mice at 4 months post H pylori infection. Notably, H pylori infection led to more severe gastric metaplasia lesion in Ddit4-knockout mice. The proteomic profiling revealed an increase in ferroptosis in the gastric tissues of infected Ddit4-deficient mice, compared with infected wild-type mice. Mechanistically, knockout of DDIT4 promoted H pylori-induced ferroptosis through the accumulation of lipid peroxides and ROS levels, and alterations in proteins such as GPX4, ALOX15, and HMOX1. Overexpression of DDIT4 counteracted H pylori-induced stem cell marker CD44V9 through modulation of ferroptosis. Similarly, in another mouse model of gastric metaplasia treated with tamoxifen, as well as in human GIM tissues, we observed the loss of DDIT4 and induction of ferroptosis. CONCLUSIONS: Our results indicate that DDIT4 serves as a protective factor against H pylori-induced gastric metaplasia by metabolic resistance to ferroptosis.

Ferroptosis↗

PubMed1979

Endoscopic diagnosis of intestinal metaplasia in asymptomatic (control) volunteers.

The F-P border and strain phenomenon of the gastric mucosa were investigated by the application of methylene blue dye spraying method in endoscopy to 105 asymptomatic control volunteers and the following results were obtained; 1. The pyloric metaplasia is observed in the fundic gland area from the twenties in age and becomes increasing in its number and move widely spreading from the lesser curvature to the anterior and/or posterior wall of the corpus with advancing age. 2. The intestinal metaplasia arises from the thirties in age. 3. The intestinal metaplasia is observed either in the pyloric gland area of following the pyloric metaplasis in the fundic gland area. 4. Histologically, the strain phenomenon of the gastric mucosa is closely related to the intestinal metaplasia. Then, methylene blue dye spraying method is reevaluated to be useful for a precise endoscopic diagnosis of intestinal metaplasia.

Adult↗

PubMed1975

The cell proliferation of epithelial metaplasia in the prostate gland. An autoradiographic in vitro study.

In 147 autoradiographically examined prostate biopsy cylinders 5.4% squamous metaplasia and 6.0% transitional metaplasia were diagnosed. The average labeling index of squamous metaplasia was 4.3% and corresponded with values from non-keratinizing squamous epithelium in other locations. The labeling index of the transitional cell metaplasia was, in contrary, almost 10 times lower with an average value of 0.29% and corresponded with the values well known for the urothelium of the urinary bladder. Higher labeling indices were observed in 2 cases but these had chronic prostatitis. The autoradiographic results are in good agreement with the ultrastructural findings in which the metaplastic squamous epithelium corresponds with normal squamous epithelium by which the cellular proliferation takes place only in the stratum basale. On the other hand, transitional metaplasia exhibits DNA-synthesizing cells in the superficial cell layers just like in the urothelium.

Autoradiography↗

PubMed1977

The diagnostic significance of intestinal metaplasia in endoscopic gastric biopsies.

The incidences of intestinal metaplasia in two groups of benign endoscopic biopsies taken from stomachs with malignant and benign lesions respectively were compared. 315 single biopsies were taken from stomachs with proven carcinoma, but outside the carcinomatous area. They were compared to 786 single biopsies taken from stomachs with proven benign lesions. Each single biopsy was placed in one of three groups: intestinal metaplasia absent, or making up less or more than 50 per cent of the epithelium in the biopsy. The results showed that single biopsies with intestinal metaplasia regardless of the extension of the metaplasia in the biopsy were found more often in stomachs with carcinoma than in stomachs with benign lesions but without any significant difference. If more than half of the benign biopsies taken during an examination demonstrated extensive grades of intestinal metaplasia a sligtly significant difference in favour of carcinomas was found.

Biopsy↗