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1.
Barrett's esophagus, morphologically analogous to gastric intestinal metaplasia, often precedes the development of esophageal adenocarcinoma. In the stomach, expression of sulfomucins and aberrant Lewis(a) (Le[a]) antigen is an excellent predictor of premalignant progression, and Helicobacter pylori infection is a crucial determinant for the development of atrophy, metaplasia, and adenocarcinoma. In the esophagus, the significance of sulfomucin expression is controversial, the aberrant expression of Le(a) has not been explored, and the role of H pylori in the evolution of preneoplastic conditions is unknown. We investigated in 155 patients referred for endoscopy the association of Barrett's esophagus with expression of sulfomucins, Lewis, secretor, and ABO phenotypes, and H pylori infection. We report a subtype of intestinal metaplasia, present in all patients with esophageal adenocarcinoma, similar to gastric intestinal metaplasia of colonic type (type III or incomplete), that expresses sulfomucins and aberrant Le(a) in goblet and columnar cells. Lewis(a+b-), nonsecretor and blood group A phenotypes, were all positively associated with esophageal adenocarcinoma, suggesting a genetic susceptibility. H pylori infection was detected in 75% of patients with esophageal adenocarcinoma.  相似文献   

2.
Columnar epithelium-lined esophagus (Barrett's esophagus) is an acquired disorder associated with a high incidence of adenocarcinoma of the lower esophagus. Columnar epithelium resembling intestinal metaplasia (IM) is especially important, since it is considered to be a premalignant condition. The aim of this study was to define the sulfated carbohydrate chain of mucin and its core peptide profile in Barrett's esophagus (BE) and to compare it with the profile in Barrett's adenocarcinoma and lower esophageal adenocarcinoma. The sulfated carbohydrate chain was not expressed in 16 specimens of normal esophageal epithelium, but in BE, it was expressed in 50% (8/16) of the specimens. This chain was detected in 100% (7/7) of esophageal adenocarcinoma specimens, including four cases of Barrett's adenocarcinoma. These data suggest that the sulfated carbohydrate chain may be associated with malignant phenotype of the esophagus. MUC1 core peptide was positive in 87% (13/15) of BE specimens and in 29% (2/7) of the esophageal adenocarcinoma specimens. MUC2 core peptide was present in 57% (8/14) and 43% (3/7) of these specimens, respectively. These data suggest that Barrett's epithelium, which is similar to IM, but not normal esophageal epithelium, expresses the sulfated sugar chain which is known to be present in gastric IM and colonic mucosa. However, there was no significant correlation between the expression of the sulfated sugar chain and the expression of either mucin core peptide MUC1 or MUC2. Thus, this carbohydrate chain may be expressed on as yet unidentified core proteins, other than MUC1 or MUC2 core peptide, in BE and esophageal adenocarcinoma. Identification of these proteins may be very important in helping to detect premalignant status in BE.  相似文献   

3.
OBJECTIVE: Barrett's esophagus is associated with significantly increased risk of development of esophageal adenocarcinoma. Replacing columnar epithelium with the normal squamous lining in this condition offers the possibility of decreasing the risk of degeneration to invasive adenocarcinoma. This study aimed to establish the feasibility of argon beam plasma coagulation (ABPC), in conjunction with control of gastroesophageal reflux, to restore the squamous lining. METHODS: Thirty patients with Barrett's esophagus (four low-grade dysplasia, three high-grade) were recruited from our surveillance program, and underwent endoscopic ABPC. RESULTS: Twenty-seven patients completed treatment, with macroscopic replacement of their columnar lining by squamous epithelium, histologically confirmed in all 27, and followed up for a median of 9 months (range, 6-18 months). Two patterns of squamous replacement were identified: 70% of patients showed squamous epithelium with no persistent intestinal metaplasia, and in 30% the new squamous epithelium covered areas of underlying intestinal metaplasia. One patient has withdrawn from the study. Two esophageal perforations, with one death, occurred early in the study. CONCLUSION: ABPC, in conjunction with control of gastroesophageal reflux, allows squamous regrowth in both benign and dysplastic Barrett's esophagus. Despite the theoretical safety advantages of ABPC over techniques such as laser, esophageal perforation may occur with this technique. It is too soon to recommend ABPC for dysplastic or nondysplastic Barrett's because follow-up is too short to show a decreased incidence of and mortality from adenocarcinoma.  相似文献   

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OBJECTIVE: In Barrett's adenocarcinomas, in contrast to squamous oesophageal carcinomas, K-ras point mutations are thought to be a frequent event. The frequency of K-ras point mutations in premalignant forms of Barrett's oesophagus (metaplasia, dysplasia) leading to adenocarcinoma with increased risk is currently not known. To establish the frequency of K-ras mutations in premalignant forms of Barrett's oesophagus, we investigated oesophageal biopsy specimens with Barrett's metaplastic and dysplastic epithelium for point mutations in the K-ras gene/codons 12, 13. DESIGN: A total of 412 biopsies from patients with Barrett's oesophagus were histologically classified into biopsies with metaplasia (n = 252), dysplasia (n = 105) and adenocarcinoma (n = 11), as well as biopsies distant from disease (normal, n = 37 and hyperplastic squamous epithelium, n = 7). METHODS: DNA from biopsy specimens was amplified by polymerase chain reaction (PCR) with a modified primer for generating a restriction site in the case of wild type in codon 12. Wild-type or point mutations in the K-ras gene/codons 12, 13 were detected by restriction fragment length analysis of the PCR products. RESULTS: Point mutations in K-ras/codon 12 were found in 9 biopsies (n = 1 in metaplasia, n = 4 in dysplasias, n = 4 in adenocarcinomas). All the other biopsies showed the wild type of K-ras/codon 12. No K-ras/codon 13 mutation (GGCgly-->GACasp) was observed. CONCLUSION: Mutations in K-ras/codon 12 were rarely found in premalignant forms of Barrett's oesophagus. Whereas the screening for K-ras point mutations in metaplastic sites of Barrett's epithelium seems not to be of practical value, the screening for mutations in dysplastic lesions might be helpful to estimate the individual risk for progression of Barrett's epithelium to adenocarcinoma. A further evaluation in larger numbers of patients is needed.  相似文献   

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Loss of heterozygosity (LOH) of 9p21, which contains the p16INK4a tumor suppressor gene locus, is one of the most frequent genetic abnormalities in human neoplasia, including esophageal adenocarcinomas. Only a minority of Barrett's adenocarcinomas with 9p21 LOH have a somatic mutation in the remaining p16 allele, and none have been found to have homozygous deletions. To determine whether p16 promoter hypermethylation may be an alternative mechanism for p16 inactivation in esophageal adenocarcinomas, we examined the methylation status of the p16 promoter in flow-sorted aneuploid cell populations from 21 patients with premalignant Barrett's epithelium or esophageal adenocarcinoma. Using bisulfite modification, primer-extension preamplification, and methylation-specific PCR, we demonstrate that the methylation assay can be performed on 2 ng of DNA (approximately 275 cells). Eight of 21 patients (38%) had p16 promoter hypermethylation and 9p21 LOH, including 3 patients who had only premalignant Barrett's epithelium. Our data suggest that promoter hypermethylation with LOH is a common mechanism for inactivation of p16 in the pathogenesis of esophageal adenocarcinomas.  相似文献   

8.
In Barrett's esophagus, the squamous lining of the lower esophagus is replaced by columnar epithelium. Barrett's esophagus is associated with gastroesophageal reflux and an increased risk of the development of esophageal cancer. Endoscopy shows red columnar epithelium in the lower esophagus. Biopsy is needed to confirm intestinal metaplasia. Some cases progress from dysplasia to invasive adenocarcinoma. Medical or surgical antireflux treatment controls symptoms and esophagitis, but Barrett's esophagus remains. Patients are usually followed up by endoscopy for detection of dysplasia or early cancer. For patients with low-grade dysplasia, follow-up is adequate; however, for those with high-grade dysplasia, esophagectomy or experimental endoscopic mucosal ablation is advised.  相似文献   

9.
Barrett's esophagus is a premalignant metaplastic change in the lining of the distal esophagus. It represents a peculiar form of healing which occurs in response to chronic gastroesophageal reflux disease. The condition should be considered in all patients undergoing endoscopy for symptoms of reflux disease and is confirmed when any biopsy shows the presence of specialized intestinal metaplasia irrespective of the macroscopic appearance of the distal esophagus. Endoscopic surveillance with multiple biopsy sampling of the esophageal mucosa is indicated for all medically fit patients with Barrett's esophagus. The diagnosis of dysplastic change within this abnormal mucosa requires histological examination of the biopsies by 2 independent but experienced pathologists. Identification of high-grade dysplasia heralds the development of invasive cancer and offers the physician an opportunity to intervene. Despite extensive endoscopic sampling of the esophageal mucosa the differentiation between high-grade dysplasia and invasive adenocarcinoma is unreliable. Esophagectomy remains the treatment of choice for patients with high-grade dysplasia since adenocarcinoma of the esophagus carries such a poor prognosis.  相似文献   

10.
BACKGROUND: Barrett's oesophagus is a premalignant condition leading to adenocarcinoma. The incidence of adenocarcinoma of the oesophagus and the gastrooesophageal junction is rapidly increasing in the USA, northern and central Europe. Data from southern Europe are still unavailable. OBJECTIVE: To evaluate the incidence of oesophageal adenocarcinoma in a large cohort of Italian patients with Barrett's oesophagus. METHODS: A total of 344 patients (253 males and 91 females, age range 19-75 years) with histologically proven Barrett's oesophagus (length of metaplasia > or = 3 cm) were enrolled from November 1987 to June 1995. Endoscopic and histological examinations were scheduled at yearly intervals. RESULTS: One hundred and eighty-seven patients complied with the follow-up. The mean duration of the follow-up period was 36 months (total follow-up 562 patient-years; range 12-90 months). Low grade dysplasia was found in five patients at the initial examination. During the surveillance period, dysplasia increased in frequency as well as in severity and was found exclusively in the intestinal type of Barrett's oesophagus. In all, dysplastic changes were found in seven patients (five low grade and two high grade) and adenocarcinoma developed in three patients during the follow-up. In a single case, both adenocarcinoma and specialized columnar epithelium developed without any evidence of dysplasia or intestinal metaplasia at the previous follow-up examination. This prospective study shows an incidence of adenocarcinoma in Barrett's oesophagus of 1/187 patient-years. When only patients with specialized columnar epithelium were considered, the risk of adenocarcinoma was 1/88 patient-years. CONCLUSION: The present report shows that the incidence of adenocarcinoma in Italian Barrett's oesophagus patients is in the range of that reported from other Western countries.  相似文献   

11.
The authors report a case of a 13-year-old girl with Barrett's esophagus who underwent antireflux surgery and was subsequently treated with endoscopic thermal coagulation using bipolar electrocoagulation. Follow-up endoscopy 15 months after completion of the endoscopic therapy showed normal esophageal mucosa without intestinal metaplasia. Longer follow-up is needed to assess the long-term effects of endoscopic treatment of the Barrett's mucosa with thermal coagulation, and this procedure should still be considered under investigation.  相似文献   

12.
Barrett's esophagus (i.e. columnar epithelial metaplasia in the distal esophagus) is an acquired condition that in most patients results from chronic gastroesophageal reflux. It is a disorder of the white male in the Western world with a prevalence of about 1/400 population. Due to the decreased sensitivity of the columnar epithelium to symptoms, Barrett's esophagus remains undiagnosed in the majority of patients. Gastroesophageal reflux disease in patients with Barrett's esophagus has a more severe character and is more frequently associated with complications as compared with reflux patients without columnar mucosa. This appears to be due to a combination of a mechanically defective lower esophageal sphincter, inefficient esophageal clearance function, and gastric acid hypersecretion. Excessive reflux of alkaline duodenal contents may be responsible for the development of complications (i.e., stricture, ulcer, and dysplasia). Therapy of benign Barrett's esophagus is directed towards treatment of the underlying reflux disease. Barrett's esophagus is associated with a 30- to 125-fold increased risk for adenocarcinoma of the esophagus. The reasons for the dramatic rise in the incidence of esophageal adenocarcinoma, which occurred during the past years, are unknown. High grade dysplasia in a patient with columnar mucosa is an ominous sign for malignant degeneration. Whether an esophagectomy should be performed in patients with high grade dysplasia remains controversial. Complete resection of the tumor and its lymphatic drainage is the procedure of choice in all patients with a resectable carcinoma who are fit for surgery. In patients with tumors located in the distal esophagus, this can be achieved by a transhiatal en-bloc esophagectomy and proximal gastrectomy. Early adenocarcinoma can be cured by this approach. The value of multimodality therapy in patients with advanced tumors needs to be shown in randomized prospective trials.  相似文献   

13.
BACKGROUND: Apoptosis maintains cell homeostasis. Altered apoptosis is involved in carcinogenesis. It was our aim to investigate whether reflux esophagitis may alter apoptosis in the esophageal mucosa and whether antireflux surgery may restore normal apoptosis. METHODS: Apoptosis was studied preoperatively and postoperatively in esophageal biopsies of 39 patients with various grades of reflux esophagitis and in Barrett's mucosa using the TUNEL method. Biopsies were also taken from lesions of the squamous epithelium adjacent to the Barrett's mucosa. RESULTS: Apoptosis increased with the severity of esophagitis. Apoptosis was low in Barrett's epithelium. Squamous epithelium adjacent to Barrett's mucosa showed increased apoptosis. After surgery apoptosis decreased in squamous epithelium, and it remained low in Barrett's epithelium. CONCLUSIONS: Apoptosis in reflux esophagitis may be protective against increased proliferation. Low apoptosis following antireflux surgery indicates that surgery is effective to prevent reflux-induced cell proliferation. Inhibition of apoptosis in Barrett's may promote carcinogenesis. This may not change following surgery.  相似文献   

14.
OBJECTIVE: To determine if the monoclonal antibody 7E12H12, which reacts with a 40 kDa protein in normal human enterocytes and has been shown to be a marker for intestinal metaplasia and adenocarcinoma arising in the bladder, could assist in distinguishing prostatic, urachal and vesical adenocarcinoma, using a sensitive immunohistochemical assay. MATERIALS AND METHODS: Fifteen primary prostatic adenocarcinomas and five adenocarcinomas of the urinary bladder were selected for a retrospective evaluation. The monoclonal antibody 7E12H12 (IgM isotype) was used in an immunoperoxidase assay to survey formalin-fixed, paraffin-embedded archival tissue specimens. RESULTS: All vesical adenocarcinomas reacted positively with the antibody, regardless of grade; none of the 15 prostatic specimens reacted positively in either the benign or malignant glandular epithelium. CONCLUSION: The monoclonal antibody 7E12H12 can differentiate primary adenocarcinoma of the bladder from secondary adenocarcinoma arising in the prostate and may be a useful tool in diagnostic pathology.  相似文献   

15.
A case of adenocarcinoma of the renal pelvis is presented. The patient was an 84-year-old man suffering from long-standing right-sided nephrolithiasis. Surgical resection of the right kidney revealed adenocarcinoma with slight stromal invasion. A tubulovillous adenoma, which was morphologically similar to an adenoma of the large intestine, was also found adjacent to the adenocarcinoma. The pelvic epithelium neighboring the lesion revealed intestinal metaplasia. Histochemical studies revealed that the tumor in the patient and adenocarcinomas or adenomas of the large intestine have similar properties of cytoplasmic mucin. These findings suggest that the epithelium with intestinal metaplasia may have developed into the adenoma and finally transformed into the adenocarcinoma. In addition, only tumor cells with severe atypia, most of which morphologically corresponded to adenocarcinoma, demonstrated positive nuclear staining for anti-p53. This suggests that p53 may play an important role in the malignant transformation of adenomas into adenocarcinomas, as is the case in the large intestine.  相似文献   

16.
Helicobacter pylori (HP) infection, a cause of multifocal atrophic gastritis, is considered an important factor related to the evolution of the human gastric mucosa from normal to intestinal-type adenocarcinoma. We examined cell proliferation and both double and single strand DNA damage in situ in 35 patients undergoing gastrectomy for adenocarcinoma with HP-infected gastric mucosa by immunolocalization of Ki-67, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling, and in situ nick translation. We also studied the distribution of intraepithelial neutrophils by elastase immunolocalization. HP infection was confirmed in all cases by serum anti-HP antibodies, ureas testing, and histopathological examination. HP-infected gastric mucosa was classified according to the degree of inflammation and intestinal metaplasia. Ki-67, terminal deoxynucleotidyl transferase-mediated labeling, in situ nick translation, and intraepithelial neutrophil indices all increased with the progression of gastritis and were highest in glands with incomplete intestinal metaplasia. All indices were lowest in gastric glands with complete intestinal metaplasia. Significant positive correlations were observed among these markers. Increased proliferative activity in HP-associated chronic gastritis in response to cell damage or injury was clearly demonstrated, suggesting that both HP-associated toxins and intraepithelial neutrophils are important in HP-related gastric epithelial injury. Increased cell turnover associated with incomplete intestinal metaplasia may result in DNA instability and subsequent development of intestinal-type gastric adenocarcinoma in HP-infected mucosa.  相似文献   

17.
Helicobacter pylori seem to avoid areas of intestinal metaplasia in the gastric mucosa, but attachment of these bacteria to epithelium with the appearance of incomplete intestinal metaplasia has been documented. To characterize the nature of the epithelium to which H pylori was attached, we carried out an immunohistochemical study using monoclonal antibodies against gastric surface mucous cell mucins (M1), blood group-related carbohydrates antigens (Le(a), sialyl Le(a), Le(b), type 1H, and type 2H) and sialyl Tn antigen. The results of this study suggest that these areas of H pylori attachment represent a hybrid epithelium whose cells share characteristics of both gastric surface mucous cells and intestinal metaplastic cells. Whether all areas of incomplete intestinal metaplasia represent an intermediate stage between the normal gastric epithelium and the fully developed complete type of metaplasia remains to be determined.  相似文献   

18.
AIMS: An increased risk of adenocarcinoma of the oesophagus has been demonstrated in patients with long segments of Barrett's mucosa. The risk of cancer associated with short segments of metaplasia of the oesophagogastric junction is not known. METHODS AND RESULTS: We report a case of early adenocarcinoma of the oesophagus arising on short tongues of Barrett's mucosa associated with an oesophageal cyst. The patient was a 68-year-old man with no previous clinical history of gastro-oesophageal reflux disease. The fortuitous discovery of an oesophageal cyst lead to the diagnosis of short tongues of Barrett's mucosa with high-grade dysplasia. On pathological examination of the resected specimen, an early adenocarcinoma had developed in Barrett's mucosa, localized just above the oesophageal cyst. CONCLUSIONS: As oesophageal cysts can cause symptoms suggestive of reflux, we hypothesize that this association may not be fortuitous.  相似文献   

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Although adenocarcinoma of the stomach has decreased in incidence over the past several decades, cancer of the gastric cardia has increased rapidly over this time frame. There are several differences between adenocarcinoma of the cardia and distal stomach with respect to epidemiology, risk factors, and prognosis. In addition, recent data raise questions with regard to possible associations of cardia cancer with Barrett's esophagus, intestinal metaplasia of the cardia, and Helicobacter pylori. This article will review the current literature with regard to this important tumor and explore these potential disease associations.  相似文献   

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