Histopathological diagnosis of Barrett's mucosa and associated neoplasias: results of a consensus conference of the Working Group for Gastroenterological Pathology of the German Society for Pathology on 22 September 2001 in Erlangen

p53 Immunohistochemistry expression in Wilms tumor: a prognostic tool in the detection of tumor aggressiveness

PURPOSE

We studied whether immunohistochemical expression of p53 in Wilms tumors correlates with tumor aggressiveness. We also examined whether preoperative chemotherapy results in any alteration of p53 expression.

MATERIALS AND METHODS

A total of 18 patients underwent preoperative chemotherapy and 30 underwent immediate surgery for Wilms tumor. All children were younger than 10 years and had histologically confirmed disease. Patients with a bilateral tumor or a syndrome related to Wilms tumor were excluded. All pathology slides were uniformly stained for p53 protein, and p53 staining density and intensity were scored. The p53 scoring was then compared to the clinical behavior of the Wilms tumor, ie unfavorable tumor staging, and survival and recurrence rates.

RESULTS

In the direct surgery and the preoperatively treated groups p53 positivity correlated with unfavorable Wilms tumor staging (p = 0.007). In addition, a positive p53 correlation predicted poorer survival (p = 0.017). Interestingly patients who underwent preoperative chemotherapy had an increased intensity of p53 staining compared to the direct surgery group (p <0.001).

CONCLUSIONS

This study provides preliminary evidence that a higher score for immunohistochemical p53 expression correlates with unfavorable Wilms tumor staging and predicts poorer survival. This test could become a useful addition to the current histopathological analysis of Wilms tumor.

Ki-67 Antigen Overexpression Is Associated with the Metaplasia-Adenocarcinoma Sequence in Barrett's Esophagus

Introduction. The objective of this study was to evaluate Ki-67 antigen expression in patients with Barrett's esophagus and esophageal adenocarcinoma and to assess its correlation with the metaplasia-esophageal adenocarcinoma progression. Methods. Using immunohistochemistry we evaluated the Ki-67 index in patients with Barrett's esophagus, esophageal adenocarcinoma, and controls. We included patients with endoscopically visible columnar mucosa of the distal esophagus (whose biopsies revealed specialized intestinal-type metaplasia), patients with esophageal and esophagogastric tumors types I and II, and patients with histologically normal gastric mucosa (control). Results. In the 57 patients studied there were no statistically significant differences between the groups with respect to age or race. Patients with cancer were predominantly men. The Ki-67 index averaged 10 ± 4 % in patients with normal gastric mucosa (n = 17), 21 ± 15 % in patients with Barrett's esophagus (n = 21), and 38 ± 16 % in patients with cancer (n = 19). Ki-67 expression was significantly different between all groups (P < 0.05). There was a strong linear correlation between Ki-67 expression and the metaplasia-adenocarcinoma sequence (P < 0.01). In patients with cancer, Ki-67 was not associated with clinical or surgical staging. Conclusions. Ki-67 antigen has increased expression along the metaplasia-adenocarcinoma sequence. There is a strong linear correlation between Ki-67 proliferative activity and Barrett's carcinogenesis.

Barrett's esophagus. Practical issues for daily routine diagnosis

Most clinicians and researchers agree that Barrett's esophagus (BE) is a precancerous condition which, however, is not easily defined. Whether goblet cells must be present or not is a matter of debate and definitions vary worldwide. Although the use of the term "columnar metaplasia" tends to circumvent these issues, it can also be subdivided into those with and without goblet cells. There is some evidence that Barrett's esophagus results from a multistep process in which goblet cells are a secondary event. Hence, Barrett's adenocarcinoma has recently been shown to originate from areas lacking goblet cells. The histological diagnosis of neoplasia is often hampered by marked interobserver variation. New endoscopic techniques allow for local resections of neoplasia with curative intent. Pathologists should know which pieces of information gastroenterologists need for management options: surveillance versus therapy such as endoscopic resection with or endoscopic ablation without histological specimen. The most important information for gastroenterologists is whether there is neoplasia or not; if any, they need to know the grade (low grade, high grade, carcinoma) and risk factors (vessel permeation, poor differentiation, resection complete in case of endoscopic resection, depth of infiltration).

The pattern of invasion of early carcinomas in Barrett's esophagus is dependent on the depth of infiltration

The differential diagnosis "high-grade intraepithelial neoplasia" or "well-differentiated Barrett's adenocarcinoma limited to the mucosa" is controversial. We investigated 277 endoscopically resected specimens of early Barrett's carcinoma. Depth of infiltration was classified as follows: m 1=carcinoma limited to Barrett's mucosa; m 2=carcinoma infiltrating the neo-muscularis mucosae; m 3=infiltration of the original lamina propria of the esophageal mucosa; m 4=infiltration of the original muscularis mucosae; sm 1, sm 2, and sm 3=infiltration into the upper third, middle third, and lower third of the submucosa. The pattern of invasion was classified and graded as follows: tubular (D 0)=only neoplastic tubuli showing cytologic criteria of malignancy - no tumor cell dissociation; dissociation grade 1 (D 1)=few dissociated tumor cells; D 2=moderate amount of dissociated tumor cells; D 3=pronounced tumor cell dissociation. 74-96% of m 1-m 4 Barrett's carcinomas limited to the mucosa have a D 0-pattern. Tubular invasion decreases only when the submucosa has been infiltrated (sm 1: 70.4%, sm 2: 30.0%, sm 3: 24.0%). Our study shows that the pattern of invasion in early cancer in Barrett's esophagus statistically significantly depends on depth of infiltration.

Immunoreactivity of cytokeratins 7 and 20 in goblet cells and columnar blue cells in patients with endoscopic evidence of Barrett's esophagus

CONTEXT

Barrett's esophagus is characterized by the presence of goblet cells. However, when alcian-blue is utilized, another type of cells, called columnar blue cells, is frequently present in the distal esophagus of patients with endoscopic evidence of Barrett's esophagus. Cytokeratin 7 and 20 immunoreactivity has been previously studied in areas of intestinal metaplasia at the esophagogastric junction. However, the expression of these cytokeratins in columnar blue cells has not been characterized.

OBJECTIVE

To compare the expression of cytokeratin 7 and 20 in goblet cells and columnar blue cells in patients with endoscopic evidence of Barrett's esophagus.

METHODS

Biopsies from 86 patients with endoscopic evidence of Barrett's esophagus were evaluated. The biopsies were stained for cytokeratin 7 and 20.

RESULTS

Goblet cells were present in 75 cases and columnar blue cells in 50 cases. Overall, cytokeratin 7 expression was similar in goblet cells and columnar blue cells (P = 0.25), while cytokeratin 20 was more common in goblet cells (P <0.001). In individuals with both cell types, however, cytokeratin 7 staining was the same in goblet and columnar blue cells in 95% of the cases, and cytokeratin 20 staining was the same in 77%.

CONCLUSION

Goblet cells and columnar blue cells have similar immunohistochemical staining patterns for cytokeratins 7 and 20 in patients with endoscopic evidence of Barrett's esophagus.

HIF-1alpha protein expression is associated with the environmental inflammatory reaction in Barrett's metaplasia

The oxygen-regulated transcription factor subunit hypoxia inducible factor-1alpha (HIF-1alpha) is involved in angiogenesis, energy metabolism, cell survival, and inflammation. We examined the protein expression of HIF-1alpha within the progression of Barrett's sequence as well as the type and degree of the environmental inflammatory reaction. Squamous epithelium (SE), metaplastic, low- and high-grade dysplastic lesions, and tumor tissue of 57 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analyzed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. HIF-1alpha protein expression increased significantly from SE to Barrett's metaplasia (BM) (P < 0.0001). From metaplasia through low- and high-grade dysplasia to cancer, no further increase could be detected. Active and chronic inflammation were also significantly different between SE and BM (P < 0.0001) but not during further progression in the sequence. HIF-1alpha protein expression did not correlate with histopathologic parameters or survival. HIF-1alpha protein expression pattern resembles the active and chronic environmental inflammatory reaction. All were significantly increased in metaplasia compared to SE without further change in tumor development. HIF-1alpha protein expression appears to be associated with inflammatory processes in the development of BM.

Histological assessment of oesophageal columnar mucosa

This review presents the pathological features of Barrett's oesophagus, with an emphasis on the role of pathologists in the diagnosis, surveillance and treatment of the disease. The diagnosis of Barrett's oesophagus is based both on endoscopy and histology. The surveillance of patients relies on systematic biopsy sampling, looking for dysplasia - intraepithelial neoplasia. Well established classifications of dysplasia are now used by pathologists, but there remain problems with this marker. Therefore, many alternative biomarkers have been proposed, that remain of limited interest in daily practice, including DNA-ploidy, proliferation markers, and p53 abnormalities. Endoscopic improvements already allow a better selection of biopsies, and it may be that new technologies will allow 'virtual biopsies'. The role of pathologists is now extended to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

Histopathology of columnar-lined esophagus in patients with gastroesophageal reflux disease

BACKGROUND AND AIMS

The question of whether an endoscopically normal-appearing esophagogastric junction should be biopsied in patients with gastroesophageal reflux disease is controversial. We have addressed this issue using endoscopy and histopathology.

METHODS

A total of 114 consecutive patients (58 males) with symptoms of gastroesophageal reflux disease prospectively underwent endoscopy, including biopsy sampling from the esophagogastric junction. Endoscopically visible columnar-lined esophagus was defined by the presence of gastric-type mucosa above the level of the rise of the gastric folds. Histopathology was conducted using the Paull-Chandrasoma classification.

RESULTS

Of the 114 patients, 85 (74.6%) had endoscopically visible columnar-lined esophagus of length < or =0.5 cm (n = 82), 1 cm (n = 2) and 7 cm (n = 1); 29 patients (25.4%) had a normal endoscopic junction. All patients had histopathologic columnar-lined esophagus. Intestinal metaplasia and low-grade dysplasia was identified in 26 (22.8%) and 5 (4.4%) individuals, respectively, and was not statistically different in endoscopically normal vs. abnormal junction (P = 0.408 for intestinal metaplasia, P = 0.775 for low grade dysplasia). Intestinal metaplasia was independent from endoscopic esophagitis (P = 0.398) and hiatal hernia (P = 0.405).

CONCLUSIONS

Columnar-lined esophagus cannot be excluded by endoscopy. In patients with gastroesophageal reflux disease, biopsy sampling of normal-appearing junction is recommended for histopathologic exclusion of intestinal metaplasia and low-grade dysplasia.

Association of COX-2 expression with corresponding active and chronic inflammatory reactions in Barrett's metaplasia and progression to cancer

AIMS

Risk reduction for Barrett's cancer in individuals taking non-steroidal anti-inflammatory drugs has been reported. Cyclooxygenase (COX)-2, one of the inhibited enzymes, is putatively involved in Barrett's cancer pathogenesis. The aim of this study was to examine a possible association between COX-2 protein expression and the development and progression of the Barrett's metaplasia-dysplasia-carcinoma sequence and the type and degree of associated inflammatory reaction.

METHODS AND RESULTS

Squamous epithelium, metaplastic, low-grade, high-grade dysplastic lesions and tumour tissue of 49 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analysed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. Within the Barrett's sequence, a significant progressive increase in COX-2 expression was identified (P < 0.0001). The most significant differences were detected between squamous epithelium and Barrett's metaplasia (P < 0.001) and from low- to high-grade dysplasia (P < 0.0001). Active and chronic inflammation were significantly different between squamous epithelium and Barrett's metaplasia (P < 0.0001), but not during further progression in the sequence.

CONCLUSIONS

Increasing COX-2 expression in Barrett's metaplasia is significantly associated with a change in the local inflammatory reaction, but not during further progression through dysplasia to cancer. This supports the potential of a chemoprevention strategy using COX-2 inhibitors independent of the extent and type of the inflammatory reaction in Barrett's oesophagus.

Videoendoscopy and histopathology of the esophagogastric junction in patients with gastroesophageal reflux disease

BACKGROUND AND AIMS

During endoscopy the stomach is considered to rise at the level of the 'gastric' folds; however, anatomical studies have demonstrated that the proximal gastric folds may in fact be esophageal. This prospective study was designed to assess the histopathology of endoscopically visible proximal gastric folds in patients with gastroesophageal reflux disease.

METHODS

35 consecutive patients (20 males) with gastroesophageal reflux disease underwent video endoscopy, including biopsy sampling from the endoscopically visible esophagogastric junction (0 cm, 0.5 cm and 1.0 cm distal to the rise of gastric folds and 0.5 cm and 1.0 cm proximal to it). Endoscopy was digitally recorded and reviewed for assignment of biopsy level. Columnar-lined esophagus and esophagitis were cataloged according to the Paull-Chandrasoma histopathologic classification and the Los Angeles endoscopic classification.

RESULTS

Endoscopy: Normal endoscopic esophagogastric junction was seen in 11 (31%) patients and visible columnar-lined esophagus < or = 0.5 cm in 24 (69%).

HISTOLOGY

Columnar-lined esophagus extended 1.0 cm in 22.8% of patients and 0.5 cm in 51.4%, distal to the rise of the gastric folds. In all patients columnar-lined esophagus was interposed between squamous epithelium and gastric oxyntic mucosa. Thus, so-called gastric folds contained mucosa of esophageal origin in all patients. Intestinal metaplasia (Barrett esophagus) was detected in eight (22.9%) patients.

CONCLUSIONS

Endoscopy cannot exclude histopathologic columnar-lined esophagus within gastric rugae. Thus, visible 'gastric' folds should not be used for definition of the esophagogastric junction but as a reference landmark for biopsy sampling during endoscopy.

Barrett's oesophagus?a pathologist's view

Barrett's oesophagus, a precancerous condition for oesophageal adenocarcinoma, detected on endoscopy and confirmed on histology, shows intestinal metaplasia of the lower oesophagus. The significance of microscopic foci of intestinal metaplasia at the gastro-oesophageal junction, corresponding either to so-called 'ultrashort' segment Barrett's oesophagus, or to carditis with intestinal metaplasia, is still a matter of debate. The surveillance of patients with Barrett's oesophagus is still based on systematic biopsy sampling of Barrett's mucosa on endoscopy, looking for dysplasia. Although well-established classifications of dysplasia are now used by most pathologists, there remain numerous problems with this subjective marker (sampling, diagnostic reproducibility, natural history, etc). Therefore, many alternative biomarkers have been proposed, but only DNA aneuploidy, proliferation markers and p53 loss of heterozygosity/overexpression have been shown to be of some use at the present time. Some endoscopic improvements already allow a better selection of biopsies, and it may be that in future new technologies will allow 'virtual biopsies'. On the other hand, the role of pathologists now extends to the evaluation of new therapeutic modalities of early neoplastic lesions in Barrett's oesophagus, especially endoscopic mucosal resection.

Pathologic Risk Factors of Adenocarcinoma of the Gastric Cardia and Gastroesophageal Junction

Available evidence supports the existence of two major pathways of neoplastic development in the gastroesophageal region: the Barrett pathway, related to gastroesophageal reflux disease, and the gastric pathway, related to Helicobacter pylori infection. The existence of an independent junctional pathway is questionable, and gastroesophageal junction adenocarcinomas share features of esophageal and gastric adenocarcinomas. It has been impossible to accommodate all data that are provided by different levels and tools of observation in tumors that develop in the gastroesophageal region in a single, coherent classification. That is why the stratification of pathologic risk in such tumors, and their respective precursors, incorporates features from topography, histology, immunohistochemistry, and molecular pathology.

INK4a-ARF alterations in Barrett's epithelium, intraepithelial neoplasia and Barrett's adenocarcinoma

INTRODUCTION

The INK4a-ARF [CDKN2A]- locus on chromosome 9p21 encodes for two tumour suppressor proteins, p16INK4a and p14ARF, which act as upstream regulators of the Rb-CDK4 and p53 pathways. To study the contribution of each pathway to the carcinogenesis of Barrett's adenocarcinoma, we analysed the alterations of p14ARF and p16INK4a in preneoplastic and neoplastic lesions of this disease.

MATERIALS AND METHODS

After microdissection, DNA of 15 Barrett's adenocarcinomas, 40 Barrett's intraepithelial neoplasms (n=20 low- and n=20 high-grade) and 15 Barrett's mucosa without neoplasia was analysed for INK4-ARF inactivation using DNA sequence and loss of heterozygosity (LOH) analysis, methylation-specific polymerase chain reaction, restriction-enzyme-related polymerase chain reaction and immunohistochemistry.

RESULTS

We detected 9p21 LOH, p16INK4a methylation and p16INK4a mutations in Barrett's adenocarcinomas in 5 of 15 (33%), 8 of 15 (53%) and 1 of 15 (7%) patients, respectively. P14ARF was methylated in 3 of 15 (20%) adenocarcinomas. In Barrett's intraepithelial neoplasia, p16INK4a was altered in 12 of 20 (60%) high-grade and in 4 of 20 (20%) low-grade intraepithelial neoplasms. In Barrett's mucosa without intraepithelial neoplasia p16(INK4a) was methylated in one case (7%). P14ARF was intact in Barrett's mucosa without intraepithelial neoplasia.

CONCLUSIONS

We conclude that most Barrett's intraepithelial neoplasms contain genetic and/or epigenetic INK4a-ARF alterations. Methylation of p16INK4a appears to be the most frequent epigenetic defect in the neoplastic progression of Barrett's tumourigenesis.