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At least 19 recordsLinked to original sources

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

[Carcinoma metastasis in cutaneous osseous metaplasia. Differential diagnosis of osseous tumor metaplasia].

The formation of metastases in heterotopic ossifications is a very rare finding. The example of a 63-year old male who underwent Billroth II procedure because of recurrent duodenal ulcers 30 years ago and median laparotomy of the upper abdomen because of blunt abdominal trauma 9 years ago shows the formation of metastasis of a carcinoma found in the gastroenteral anastomosis in a focus of heterotopic ossification, which was located in the scar of the upper abdominal laparotomy.

Adenocarcinoma↗

PubMed1992

Subtypes of intestinal metaplasia and Helicobacter pylori.

To determine whether there is a relationship between the presence of H pylori and the various subtypes of intestinal metaplasia in the gastric antrum, 2274 antral gastroscopic biopsies from 533 patients were examined. H pylori was found in 289 patients. Intestinal metaplasia in general was found in 135 patients. Type I intestinal metaplasia was found in 133 patients (98.5%), type II in 106 patients (78.5%) and type III in 21 patients (15.6%). Ninety eight of these 135 patients (72.6%) were H pylori positive and 37 patients (27.4%) were H pylori negative. No statistically significant difference was found in the prevalence of type I and II intestinal metaplasia between the intestinal metaplasia positive and H pylori positive and intestinal metaplasia negative and H pylori negative patients. Type III intestinal metaplasia was found less often in the intestinal metaplasia positive and H pylori positive patients (11.2%) as compared with intestinal metaplasia positive and H pylori negative patients (27%) (p less than 0.05). In contrast with type I and II intestinal metaplasia type III intestinal metaplasia was found more often in moderate/severe intestinal metaplasia than in mild intestinal metaplasia (p less than 0.02). Within the group of patients with moderate/severe intestinal metaplasia, type III was found less often in the H pylori positive patients (p less than 0.05). We suggest that the gastric milieu for H pylori is less appropriate in type III intestinal metaplasia positive patients. As type III intestinal metaplasia might be regarded as a marker of possibly increased gastric cancer risk, the lower prevalence of H pylori in these type III intestinal metaplasia positive patients might be the result of severe changes in mucosal architecture.

Adult↗

PubMed1992

Intestinal metaplasia and Helicobacter pylori: an endoscopic bioptic study of the gastric antrum.

To study the relationship between intestinal metaplasia and Helicobacter pylori infection, 2274 gastroscopic antral biopsies taken from 533 patients were examined. Overall, intestinal metaplasia was found in 135 patients (25.3%) and H pylori in 289 patients (54.2%). The prevalence of intestinal metaplasia and H pylori was age related, being more common in patients greater than or equal to 50 years compared with patients less than 50 years (intestinal metaplasia, p less than 0.001 and H pylori, p less than 0.05). Intestinal metaplasia was found more often in H pylori positive patients compared with H pylori negative patients (33.9% v 15.2%, p less than 0.001). The mean age of intestinal metaplasia positive patients who were also H pylori positive was 64 (13.3) years, whereas the mean age of intestinal metaplasia positive patients who were H pylori negative was 72 (14.7) years (p less than 0.005). The extent of intestinal metaplasia was not statistically different in the latter two groups. Although our data do not prove a causal relationship between H pylori infection and the histogenesis of intestinal metaplasia it is suggested that H pylori infection is an important factor in the development of intestinal metaplasia, which is generally recognised as a precursor lesion of intestinal type gastric carcinoma.

Adult↗

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↗

PubMed1991

Carcinomas with metaplasia and sarcomas of the breast.

The clinicopathologic, immunohistochemical, and flow cytometric characteristics of 34 cases of mammary carcinoma with metaplasia were compared with those of 20 cases of pure sarcoma of the breast. All 20 of the latter tumors showed the pattern of malignant fibrous histiocytoma. There were 20 cases of carcinoma with mesenchymal metaplasia, 7 cases of carcinoma with mixed epithelial (squamous) and mesenchymal metaplasia, and 7 cases of carcinoma with epithelial metaplasia (four mixed ductal/squamous and three pure squamous cell carcinomas). No patient with pure sarcoma had lymph node metastases develop; all nodal metastases were found in patients who had carcinoma with metaplasia, although in one case the carcinomatous component was seen only within a lymph node metastasis. Epithelial antigens were found not only within the epithelial elements of all cases of carcinoma, but also within the apparent mesenchymal elements of 44% of the carcinomas showing divergent differentiation. Flow cytometric analysis of eight cases of carcinoma with mesenchymal metaplasia showed aneuploidy/tetraploidy in six neoplasms. For patient management purposes, the distinction of pure sarcoma from carcinoma with metaplasia is important, but additional subclassification of carcinoma with metaplasia is of greater biologic than clinical interest.

Adult↗

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↗

PubMed1992

Association between acute inflammatory cells in lavage fluid and bronchial metaplasia.

In epidemiologic studies, airway disease and parenchymal injury are known morbid outcomes of occupational exposure to asbestos. However, the relationship of inflammatory events considered to be responsible for parenchymal injury to the subsequent development of airway injury is unknown. To assess this we performed bronchoalveolar lavage (BAL) and airway biopsies on a population of subjects with exposure to asbestos in the workplace. As an index of airway injury, we employed histologic metaplasia seen in mucosal biopsy specimens. Lung BAL fluid was analyzed for two potentially relevant protein markers and for inflammatory cells recovered from the lower respiratory tract. We related metaplasia to demographic features of this study population (eg, smoking history and asbestos exposure data) and also to the protein and cellular markers recovered by BAL. We studied 50 workers and detected keratinizing metaplasia in 15 and varying lesser abnormalities in the other 28. Cigarette smoking was not associated with the presence of metaplasia (p less than 0.2). Smoking status was associated with an increase in BAL cells (p less than 0.02); however, neither the percent nor concentration of acute inflammatory cells was significantly increased. Acute inflammatory cells (percent and cells per milliliter of BAL fluid) were significantly increased among the subjects with severe metaplasia compared with other study subjects. This increase was true of both neutrophils and eosinophils and the sum of these two (p less than 0.02). Stratification of subjects by smoking status demonstrated a persistent association of inflammatory cells with metaplasia. By logistic regression analysis, polymorphonuclear leukocytes per milliliter and eosinophils per milliliter were significantly related to the presence of metaplasia in two independent models (odds ratios, 9.9 and 7.6, respectively). Cigarette smoking and other demographic or BAL variables were not significantly associated with metaplasia in these models.

Asbestosis↗

PubMed1992

[Squamous metaplasia of the mucosa of the human laryngeal ventricle: a clinicopathological study with reference to the possibility of de novo carcinogenesis].

Primary carcinomas are rarely encountered in the laryngeal ventricle of Morgagni. They are classified into the subgroup of supraglottic laryngeal carcinoma in the TNM classification system of malignant tumors. However, detailed investigations have not hitherto been made on the possible occurrence of carcinomas in this region of the larynx. To find out whether the laryngeal ventricle could be the site of carcinogenesis, the author examined squamous metaplasia in the mucosal epithelium of 60 human laryngeal ventricles which were taken from 38 larynges removed operatively from patients with laryngeal carcinoma (14 cases), hypopharyngeal carcinoma (20 cases), carcinoma of the upper esophagus (two cases), tracheal carcinoma (one case) or thyroid carcinoma (one case). The patients consisted of 31 males and 7 females, with an age distribution of 44 to 80, average 62.7. The laryngeal ventricles were selected for investigation only when they did not show any carcinomatous invasion macroscopically. Macroscopic observations were performed after gross staining with pyronin Y, which permits differentiation of squamous metaplasia from respiratory epithelia. Tissues were embedded in paraffin, sectioned serially and stained with hematoxylin and eosin. The clinical records of the patients were also made. The results are summarized as follows: 1. Squamous metaplasia of the stratified ciliated epithelium was found in 38 out of 60 specimens (63%) of the laryngeal ventricles examined. 2. The metaplasia seemed to be precipitated by smoking or exposure to radiation, along with aging. 3. The incidence and extent of metaplasia of the ventricular mucosa depended on the disease entity which had necessitated total laryngectomy, and the metaplasia was most prominent in cases with the supraglottic type of laryngeal carcinoma. 4. The metaplastic epithelium was occasionally associated with hyperplasia or dysplasia of the epithelium. 5. Microinvasive carcinoma was found in one laryngeal ventricle with severe metaplasia. These findings suggested a possible de novo carcinogenic process in the laryngeal ventricle through squamous metaplasia of the respiratory epithelium. From this observation, the author proposes to call carcinoma of this region of the larynx the ventricular type of laryngeal carcinoma.

Adult↗

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↗

PubMed1992

Necrotizing squamous/mucinous metaplasia in oncocytic salivary gland tumors. A potential diagnostic problem.

Tumor necrosis and squamous and/or mucinous metaplasia was found in 4 of 26 oncocytic salivary gland tumors (24 Warthin's tumors and 2 oncocytomas). The necrosis was extensive in two cases, producing architectural and cytologic atypia sufficient to simulate a squamous carcinoma. In a third tumor, necrotic and inflammatory debris occurred within dilated tumor spaces exhibiting squamous and mucinous foci, suggesting low-grade mucoepidermoid carcinoma. Adequate sampling revealed Warthin's tumors in all four cases. An additional 13 tumors showed incidental foci of squamous metaplasia, often accompanied by stromal scarring but without necrosis. Four of these tumors also had focal mucinous metaplasia. In the adjacent non-neoplastic salivary gland, oncocytic metaplasia of ducts was seen in 22 glands; there were 7 oncocytic cysts and 3 oncocytic nodules. The tumor necrosis and metaplasia are reminiscent of necrotizing sialometaplasia of the minor salivary gland, thought to be ischemic in origin. The etiology of necrotizing squamous/mucinous metaplasia described here and the extent to which oncocytosis contributes to these changes is unknown. Possibly the extravasation of oncocytic and/or mucinous secretions or cyst contents may result in the reactive changes observed. Necrotizing sialometaplasia and squamous/mucinous metaplasia of oncocytic tumors appear to be related only morphologically, but the shared histologic features may be useful in excluding the diagnosis of salivary gland carcinoma.

Adenolymphoma↗

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↗

PubMed1991

Stimulation by Bt2cAMP of epidermal mucous metaplasia in retinol-pretreated chick embryonic cultured skin, and its inhibition by herbimycin A, an inhibitor for protein-tyrosine kinase.

Epidermal mucous metaplasia of cultured 13-day-old chick embryonic tarsometatarsal skin can be induced by culture in medium containing retinol (20 microM) for only 8-24 h and then in a chemically defined medium without vitamins or serum for 6 days. In the induction of mucous metaplasia, retinol primarily affects the dermal cells and a signal(s) induced in the dermis by excess retinol alters epidermal differentiation toward secretory epithelium. In this work we found that Bt2cAMP (2 mM) stimulated mucous metaplasia severalfold when added to retinol-pretreated skin but inhibited epidermal mucous metaplasia when added together with retinol. Forskolin (100 microM), an activator of adenylate cyclase, also stimulated mucous metaplasia when added to retinol-pretreated skin. On the other hand, transduction in the epidermal cells of a signal(s) induced in dermal cells by excess retinol was inhibited by herbimycin A (500 ng/ml), an inhibitor of protein-tyrosine kinases, and TPA (0.1 microM), an activator of protein kinase C. Hence these findings indicated that cAMP stimulated signal-induced mucous metaplasia, and that transduction of the signal(s) in the epidermal cells required protein-tyrosine kinase and was inhibited by protein kinase C.

Adenylyl Cyclases↗

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↗