[Performance of record linkage for cancer registry data linked with mammography screening data]. / Zur Leistungsfähigkeit des Record-Linkage zwischen epidemiologischen Krebsregistern und dem Mammographie-Screening.

The evaluation of the German Mammography Screening Program requires record linkage with data from cancer registries in order to measure the number of false-negative mammograms and interval cancers. This study aims at evaluating the performance of the established linkage method based on identifiers encrypted by the standard procedure of the German cancer registries. In addition, the results are compared with an alternative method based on plain text identifiers. A total of 16,572 records from the Bremen Mammography Screening Pilot Study were linked with data from the Bremen Cancer Registry. Based on a gold standard set of matching record pairs, homonym and synonym errors were determined. Given the customary threshold value in cancer registries, the plain text method showed a lower rate of synonym errors (2.1-5.1%) and a lower rate of homonym errors (0.01-0.15%). As 10.4 million women are invited to take part biennially in screening, the corresponding figures would be 3,237 homonym errors for the standard procedure and 294 using the plain text method provided equivalent conditions. The 11-fold increase in the homonym error rate documents the trade-off for better data protection using encrypted data.

Human defensin 5 expression in intestinal metaplasia of the upper gastrointestinal tract.

BACKGROUND: Upper gastrointestinal tract intestinal metaplasia (IM) is termed Barrett's oesophagus (BO) or gastric intestinal metaplasia (GIM), depending on its location. BO and GIM are associated with chemical exposure resulting from gastro-oesophageal reflux and chronic Helicobacter pylori infection, respectively. Paneth cells (PCs), characterised by cytoplasmic eosinophilic granules, are found in a subset of IM at these sites, but histology may not accurately detect them. AIM: To determine human defensin 5 (HD5; an antimicrobial peptide produced by PCs) expression in BO and GIM, and to investigate its association with H pylori infection. METHODS: Endoscopic biopsies from 33 patients with BO and 51 with GIM, and control tissues, were examined by routine histology and for H pylori infection and HD5 mRNA and protein expression. RESULTS: In normal tissues, HD5 expression was specific for PCs in the small intestine. Five patients with BE and 42 with GIM expressed HD5, but few HD5 expressing cells in IM had the characteristic histological features of PCs. Most HD5 positive specimens were H pylori infected and most HD5 negative specimens were not infected. CONCLUSIONS: HD5 immunohistochemistry was often positive in IM when PCs were absent by conventional histology. Thus, HD5 immunohistochemistry may be superior to histology for identifying metaplastic PCs and distinguishing GIM from BO. The higher frequency of HD5 expression in GIM than in BO is associated with a higher frequency of H pylori infection, suggesting that in IM PCs may form part of the mucosal antibacterial response.

Pathological subgroups may predict complications but not late failure after ileal pouch-anal anastomosis for indeterminate colitis.

INTRODUCTION: Ileal pouch-anal anastomosis (IPAA) for indeterminate colitis (IndC) may lead to an increased risk of perineal complications and pouch loss. This study evaluated pathological subgroups of IndC to identify a predictor of increased complication rates after IPAA for IndC. PATIENTS AND METHODS: Of 171 IPAAs with a postoperative diagnosis of IndC, IndC was confirmed in 115 of the 140 specimens available for re-examination. These were divided into IndC favouring ulcerative colitis (Group I; n = 99), 'true' IndC (Group II; n = 8), and IndC favouring Crohn's (Group III; n = 8). 61 presented with fulminant colitis. Patients in Group I were subdivided into having (A) deep ulcers (B) transmural lymphoid aggregates (C) skip lesions (D) terminal ileal inflammation and/or (E) a caecal patch. Outcome was determined by chart analysis, and compared to 231 randomly selected patients with IPAA for ulcerative colitis (UC) matched for age, gender, and follow-up. RESULTS: Only patients with evidence of deep ulceration (Group IA) had a significant increase in the incidence of Crohn's disease (4.3%vs. 0.43%, P = 0.04), complex perianal fistulae (4.3%vs. 0.43%, P = 0.04), and pelvic abscess (12.9%vs. 2.2%, P < 0.001). No pathological subgroup of IndC patients had a significantly different rate of pouch failure or pouch loss. CONCLUSIONS: Pathological stratification may predict those more likely to develop Crohn's disease or other complications, but not pouch failure. On this basis, we feel that patients with IndC should not be precluded from having IPAA surgery.

Mushroom poisoning--from diarrhea to liver transplantation.

Mushroom poisoning from the genus Amanita is a medical emergency, with Amanita phalloides being the most common species. The typical symptoms of nausea, vomiting, abdominal pain, and diarrhea are nonspecific and can be mistaken for gastroenteritis. If not adequately treated, hepatic and renal failure may ensue within several days of ingestion. In this case series, patients poisoned with Amanita virosa are described with a spectrum of clinical presentations and outcomes ranging from complete recovery to fulminant hepatic failure. Although there are no controlled clinical trials, a few anecdotal studies provide the basis for regimens recommended to treat Amanita poisoning. Use of i.v. penicillin G is supported by most reports. Silibinin, although preferred over penicillin, is not easily available in the United States. In those with acute liver failure, liver transplantation can be life saving.

CO2 pneumoperitoneum does not enhance tumor growth and metastasis: study of a rat cecal wall inoculation model.

INTRODUCTION: Although many studies have evaluated the effects of carbon dioxide pneumoperitoneum on port site recurrence, little is known about its outcome on tumor growth and metastasis. The effect of pneumoperitoneum with carbon dioxide on cecal tumor growth and metastasis was compared with laparotomy using a rat colon cancer cell line. METHODS: Time Course Study: Fifty WF/BN F1 hybrid rats were inoculated with 2,000,000 WB2054M5 tumor cells into the cecal wall and explored two to ten weeks after injection. Main Study: 152 rats were randomly assigned either to 6-mmHg CO2 pneumoperitoneum (30 minutes) or 4-cm laparotomy (30 minutes) two weeks after tumor inoculation and were explored four weeks after treatment. RESULTS: Time Course Study: Thirty-seven (95 percent) of the surviving rats developed a cecal wall tumor, and there was progressive tumor growth and metastasis over the ten-week period. At six weeks, metastasis occurred to the liver in 25 percent, to the lung in 38 percent, and to the lymph node in 63 percent, and peritoneal seeding occurred in 38 percent; this time period was chosen for the main study. Main Study: At the time of treatment (2 weeks), 124 rats were eligible for randomization. One hundred two rats survived the six-week period (50 pneumoperitoneum, 52 laparotomy) and were killed. There were no differences between the CO2 pneumoperitoneum and laparotomy groups regarding cecal tumor growth (1.043 vs. 0.894 g) and metastases to the liver (32 vs. 37 percent), lung (34 vs. 17 percent), lymph node (84 vs. 77 percent), and wound or port (20 vs. 23 percent). CONCLUSIONS: A cecal wall inoculation model mimics the natural cascade of colon cancer growth and metastasis. CO2 pneumoperitoneum did not affect the tumor growth and metastasis to the liver and other organs when compared with laparotomy in this model.

Cryptogenic cirrhosis and posttransplantation nonalcoholic fatty liver disease.

Some patients diagnosed with cryptogenic cirrhosis may have "burned-out" nonalcoholic fatty liver disease (NAFL). To test this hypothesis, we used our liver transplant database (November 1984 to November 1998) to assess the incidence of NAFL in patients with cryptogenic cirrhosis after orthotopic liver transplantation (OLT). We also examined the clinicodemographic features associated with post-OLT NAFL, obtained by chart review and telephone interviews. When available, post-OLT liver biopsy specimens were reviewed blindly by a hepatopathologist according to the NAFL pathology protocol. We identified 51 patients with cryptogenic cirrhosis (mean age, 51 +/- 12 years); 60% were women, 94% were white, and 34% had type 2 diabetes mellitus (DM). Mean pre-OLT body mass index (BMI) was 27.33 +/- 5.54 kg/m(2). Twenty-five patients underwent at least 1 post-OLT liver biopsy. Post-OLT NAFL was identified in 13 patients (25.4%), whereas post-OLT nonalcoholic steatohepatitis (NASH) was seen in 8 patients (15.7%). Features associated with post-OLT NASH were pre- and post-OLT type 2 DM (P < or =.05) and an elevated fasting triglyceride level (P <.05). BMI tended to be greater in patients with post-OLT NAFL or NASH. Those who did not develop post-OLT NAFL showed a decrease in BMI. Patients with cryptogenic cirrhosis undergoing OLT resemble patients with NAFL. Post-OLT NAFL and NASH can be seen in a number of patients with cryptogenic cirrhosis. This supports the notion that some cases of cryptogenic cirrhosis represent burned-out NAFL.

Chronic hepatitis C and superimposed nonalcoholic fatty liver disease.

BACKGROUND/AIMS: Hepatitis C and nonalcoholic fatty liver disease (NAFL) are the two most common forms of liver disease in the United States. Recently, obesity and its associated risk factors have been suggested to enhance HCV-related fibrosis. The aim of this study was to assess the impact of hepatic steatosis, steatohepatitis, and its associated risk factors on HCV-related fibrosis. METHODS: Patients with untreated, biopsy-proven, chronic hepatitis C (6/97-3/99) were included. Clinical and demographic data at the time of liver biopsy were obtained from chart review and verified by telephone survey. One hepatopathologist reviewed all pathologic specimens, using the modified histological activity index score and the Ishak staging for fibrosis and a NAFL pathologic protocol. RESULTS: One hundred and seventy patients with hepatitis C were included [age: 48.7+/-9.33 (years), body mass index (BMI): 28.1+/-5.7 (kg/m2) and type 2 diabetes mellitus (DM): 14%]. Of these, 77 (45.3%) had no or mild fibrosis and 93 (54.7%) had advanced fibrosis. Hepatic steatosis was seen in 90 (52.9%) patients. The grade of steatosis was associated with markers of obesity only. Age (p=0.002), type 2 DM (p=0.04), and superimposed steatohepatitis (p=0.047) were independently associated with advanced fibrosis. Superimposed nonalcoholic steatohepatitis (NASH) was seen in 17 (10%) patients. Patients with superimposed NASH were mostly obese (76.5%), males (62%) with 16% having type 2 diabetes and a BMI 33.8+/-7.12. CONCLUSION: In patients with chronic hepatitis C, type 2 DM and superimposed steatohepatitis are independently associated with advanced fibrosis.

Interferon alpha 2B and ribavirin in severe recurrent cholestatic hepatitis C.

Severe recurrent cholestatic hepatitis C after liver transplantation has a poor prognosis and no standard therapy is currently available. Four cases of severe recurrent cholestatic hepatitis C treated with a combination of interferon alpha 2b and ribavirin are described. All four patients were transplanted for hepatitis C-related cirrhosis. The mean age at transplantation was 45 years (range 41-51 years). Three of the patients were male and one was female. All four patients had hepatitis C virus viremia before and after liver transplantation. At 2 to 23 months after liver transplantation, all four patients developed jaundice, cholestatic elevation of liver enzymes, and histopathology consistent with severe recurrent cholestatic hepatitis C. Combination of interferon and ribavirin was given with prompt virological suppression. Despite this rapid viral suppression, all four patients developed progressive graft failure with three deaths.

The utility of cytokeratin subsets in distinguishing Barrett's-related oesophageal adenocarcinoma from gastric adenocarcinoma.

AIMS: Accurate tumour classification is critical for meaningful epidemiological studies in the assessment of cancer incidence rates and trends. Differentiating primary gastric carcinoma from oesophageal carcinoma can be difficult, especially when tumours are large and involve both the oesophagus and stomach. Furthermore, adenocarcinomas of both organs typically are of intestinal histological type and arise in a background of intestinal metaplasia. Consequently, histological markers that reliably distinguish Barrett's-related oesophageal adenocarcinoma from gastric adenocarcinoma would be useful. Cytokeratins (CK)7 and 20 are cytoplasmic structural proteins with restricted expression that help to determine the origin of many epithelial tumours including those of the gastrointestinal tract. The aim of this study was to determine the utility of co-ordinate CK7 and 20 expression in the distinction of Barrett's-related oesophageal adenocarcinoma from gastric adenocarcinoma arising in a background of intestinal metaplasia. METHODS AND RESULTS: CK7 and 20 immunostaining was performed on randomly selected surgical resection specimens from patients with Barrett's-related oesophageal adenocarcinoma (n = 30) and intestinal type gastric adenocarcinoma (n = 14) arising in a background of intestinal metaplasia. A CK7+ CK20- immunophenotype was demonstrated in 27 of 30 (90%) patients with Barrett's-related oesophageal adenocarcinoma and only three of 14 (21%) gastric adenocarcinomas. The sensitivity, specificity and positive predictive value of a CK7+/20- immunophenotype for a diagnosis of Barrett's-related oesophageal adenocarcinoma was 90%, 79%, and 90%, respectively. CONCLUSIONS: A CK7+/20- tumour immunophenotype is associated with Barrett's-related oesophageal adenocarcinoma and may be useful in accurate tumour classification, thus facilitating improving epidemiological evaluation of tumours at the oesophagogastric junction.

Dynamic tissue expansion of the larynx in a canine model.

OBJECTIVES: To test whether staged, progressive, monitored, dynamic tissue expansion is possible in the larynx and to evaluate its effectiveness in dilating and augmenting constricting cicatricial lesions. DESIGN: Animal study. SETTING: Research facility, tertiary care medical center. SUBJECTS: Thirteen dogs, 3 with laryngotracheal stenosis. INTERVENTIONS: Dogs underwent laryngeal splits, tracheostomy, and insertion of inflatable stents. In 7 normal dogs, stents were progressively inflated by air in predetermined increments during 11 days. In 3 normal dogs and 3 with laryngotracheal stenosis, stents were gradually expanded by water. Stents were kept in place for 21 days. After removal, dogs were observed for 25 days. Five died of complications of tracheostomy. MAIN OUTCOME MEASURES: Airway diameter measured by endoscopy before the induction of stenosis, before the laryngeal splitting procedure, after stent removal, and before euthanasia. RESULTS: The lumen increased, then shrank somewhat after stent removal. In 2 surviving dogs with laryngotracheal stenosis and water-expanded stents, the lumen was 82.5% larger than baseline at stent removal and 71.0% larger at euthanasia. In 2 surviving normal dogs with water-expanded stents, lumen size increased by 50.0% at stent removal, and in 1 dog surviving to day 46, it was 17.0% larger. In 5 surviving dogs with air-inflated stents, lumen size was 39.0% larger at stent removal and 8.0% larger at day 46. Histologically, fibrous tissue developed in the gaps between the splayed margins of the laryngeal cartilages. CONCLUSIONS: The larynx may be dynamically expanded. Although the maximal diameter is not maintained, final cross-sectional areas are larger.

A randomized, double-blind controlled trial of interferon alpha-2b and ribavirin vs. interferon alpha-2b and amantadine for treatment of chronic hepatitis C non-responder to interferon monotherapy.

BACKGROUND/AIMS: Interferon-based regimens (alone or with ribavairin) are standard therapies for chronic hepatitis C. The aim of this study was to compare a 24-week regimen of interferon alpha-2b + ribavirin (IFN + RIBA) to interferon alpha-2b + amantadine (IFN + AMANT) in non-responders to previous interferon monotherapy. METHODS: In a multi-center, double-blind clinical trial, 118 patients (non-responders to previous interferon monotherapy) were equally randomized into the two arms: interferon alpha-2b (3 MU thrice weekly) and ribavirin (800 mg daily) vs. interferon alpha-2b (3 MU thrice weekly) and amantadine (200 mg daily). RESULTS: After 24 weeks of therapy, HCV RNA became undetectable in 34.8% (95% CI: 23.7-49.2) of IFN + RIBA and 19.6% (95% CI: 10.6-34.7) of IFN + AMANT (P = 0.10). This response was sustained in 3.9% (95% CI: 1.0-14.9) of IFN + RIBA and 0% of IFN + AMANT (P = 0.16). Ten patients from IFN + AMANT (17%) and 12 patients (20%) from IFN + RIBA were discontinued before completion of therapy. Of these, 7% in IFN + AMANT and 12% in IFN + RIBA were discontinued due to adverse effects. CONCLUSIONS: Re-treatment of interferon non-responders with a 24-week course of IFN + AMANT was not associated with any sustained viral eradication. Although IFN + RIBA in this group was associated with a reasonable end of treatment response, relapses were common and sustained responses were low.

Evaluating laryngotracheal stenosis in a canine model with virtual bronchoscopy.

We performed a prospective masked animal study to determine whether virtual bronchoscopy, a noninvasive computed tomography technique, can accurately measure upper airway stenosis. Virtual bronchoscopy creates a 3-dimensional endoscopic image from spiral computed tomography data. Laryngotracheal stenosis was endoscopically induced in 18 dogs. The excised larynges were examined by endoscopy, virtual bronchoscopy, and macrodissection. Measurements were made of the anteroposterior (A-P) diameter, the left-right (L-R) diameter, the full length of stenosis in the sagittal plane, and the length of the tightest stenotic segment. Each measurement method was performed independently. All investigators were unaware of measurements made by others. The measurements obtained through virtual bronchoscopy and actual endoscopy were compared to those made at dissection by interclass correlation coefficients (ICCs). Endoscopy was better than virtual bronchoscopy in measuring the A-P diameter (ICC = .79, p < .0001; ICC = .42, p = .01). Both were equally effective in measuring the L-R diameter (ICC = .53, p = .0062; ICC = .52, p = .0064). The endoscopes could not assess the full length of the stenosis, whereas virtual bronchoscopy measured it fairly accurately (ICC = .72, p = .0001). Virtual bronchoscopy relatively accurately measured the length of the tightest stenotic segment (ICC = .68, p = .0002), whereas endoscopy produced measurements in only 11 of 18 larynges, and the measurements were less accurate (ICC = .45, p = .0068). Virtual bronchoscopy can provide good measurements of stenotic lesions in the airway. It is more accurate than actual endoscopy in determining the length of stenosis. It may therefore be useful as an adjunct imaging method in preoperative planning for reconstructive surgery.

Cytokeratin immunoreactivity patterns in the diagnosis of short-segment Barrett's esophagus.

BACKGROUND & AIMS: The origin of intestinal metaplasia in short segments of columnar mucosa at the esophagogastric junction has clinical importance but can be difficult to determine at endoscopy. Cytokeratin (CK) 7 and 20 patterns are specific for long-segment Barrett's esophagus; however, their utility in short-segment Barrett's esophagus has not been assessed. METHODS: Endoscopic biopsy specimens from patients with long-segment Barrett's esophagus (n = 49), suspected short-segment Barrett's esophagus (n = 43), and gastric intestinal metaplasia (n = 26) were immunostained for CK7 and CK20. Comprehensive clinical data were obtained, including age, gender, and hiatal hernia and Helicobacter pylori status. RESULTS: A Barrett's CK7/20 pattern was present in 48 (98%) of 49 patients with long-segment Barrett's esophagus, 35 (82%) of 43 with suspected short-segment Barrett's esophagus, and 0 (0%) of 26 patients with gastric intestinal metaplasia. Patients with suspected short-segment Barrett's esophagus with a Barrett's CK7/20 pattern were clinically similar to those with long-segment Barrett's esophagus. In contrast, patients with suspected short-segment Barrett's esophagus with no Barrett's CK7/20 pattern were clinically similar to those with gastric intestinal metaplasia. CONCLUSIONS: A Barrett's CK7/20 pattern identifies a subset of patients with suspected short-segment Barrett's esophagus who have a patient profile similar to that seen in long-segment Barrett's esophagus. A Barrett's CK7/20 pattern is an objective marker of Barrett's mucosa that in conjunction with appropriate clinical and endoscopic data can be used by clinicians to better define patients with short-segment Barrett's esophagus.

The location and frequency of intestinal metaplasia at the esophagogastric junction in 223 consecutive autopsies: implications for patient treatment and preventive strategies in Barrett's esophagus.

The frequency of intestinal metaplasia at the esophagogastric junction is as high as 36% in endoscopy studies; the majority of cases (approximately 67%) occur in short segments of esophageal columnar mucosa. The validity of these studies has been questioned, however, because of heterogenous underlying diseases prompting endoscopy. To determine the frequency and origin of intestinal metaplasia at the esophagogastric junction, we histologically evaluated the entire esophagogastric junction for the presence of intestinal metaplasia using Alcian blue/periodic acid-Schiff mucin stains in 223 consecutive autopsies. Precise localization of the Z line in relation to the esophagogastric junction and tongues of esophageal columnar-appearing mucosa were noted in each case. Mean patient age was 47 years; 69% of patients were male, and 63% were white. Twenty five of 223 cases (11%) had intestinal metaplasia at the esophagogastric junction. Only 2 of 25 cases (8%) had intestinal metaplasia in the esophagus; the remaining 23 cases (92%) had intestinal metaplasia in the gastric cardia. Male gender, advanced age, white ethnic origin, and short tongues of esophageal columnar mucosa were not associated with gastric cardia intestinal metaplasia. An association of distal gastric intestinal metaplasia (P < .01) and chronic gastritis (P < .01) with gastric cardia intestinal metaplasia suggests a role for Helicobacter pylori infection in this process. The frequency of intestinal metaplasia at the esophagogastric junction in an unselected autopsy population is low (11%) even after exhaustive histologic evaluation using Alcian blue mucin stains. Furthermore, intestinal metaplasia is confined to the gastric cardia in more than 90% of cases with no association to male gender, white ethnic origin, advanced age, or the presence of short segments of esophageal columnar-appearing mucosa at endoscopy. These results demonstrate that caution is warranted when applying the findings of endoscopy studies to the development of preventive and screening strategies aimed at identifying Barrett's esophagus in an asymptomatic general population.

The gastric cardia: fact or fiction?

OBJECTIVE: It is unclear whether the gastric cardia is present from birth or is metaplastic and develops as a result of gastroesophageal reflux disease. To this end, we evaluated the histology of the entire esophagogastric junction in consecutive pediatric autopsies to determine the presence and extent of cardiac mucosa. METHODS: The entire esophagogastric junction of 33 consecutive pediatric (< or =18 yr) autopsies was examined. The precise location of the squamocolumnar junction and its relationship to the esophagogastric junction was noted in all cases. Slides were evaluated by two pathologists in a blinded fashion to look for cardiac mucosa, characterized by unequivocal periodic acid-Schiff (PAS)-positive mucous glands in a lobular configuration. Sections from the antrum and esophagogastric junction were examined for the presence of Helicobacter pylori. RESULTS: Three cases were excluded due to autolysis. The mean age of the 30 remaining patients was 6.3 yr (range: 16 days-18 yr). A regular-appearing squamocolumnar junction was identified at the esophagogastric junction in all 30 cases. Cardiac mucosa was present in all specimens (mean length: 1.8 mm; range: 1.0-4.0 mm), always on the gastric side of the esophagogastric junction. There was no significant association between patient age or gender and length of cardiac mucosa. None of the patients had a known history of gastroesophageal reflux disease or Barrett's esophagus, and none were taking acid-suppressing medications before death. All were negative for Helicobacter pylori by Giemsa stain. CONCLUSIONS: In an unselected pediatric patient population with little or no propensity for gastroesophageal reflux disease, a short segment of cardiac mucosa was consistently present on the gastric side of the esophagogastric junction, independent of gender or age. These results support the concept that the gastric cardia is present from birth as a normal structure.

Improved canine model for laryngotracheal stenosis.

Laryngotracheal stenosis (LTS) is a serious challenge for the otolaryngologist. Although progress has been made in preventing and treating LTS, more research is required. Existing canine models for LTS incur high mortality and morbidity, require relatively complicated procedures or costly equipment, entail lengthy waiting periods, or have unpredictable results. A simple, reliable, and inexpensive procedure, requiring no tracheotomy, is described for creating a canine model for LTS research. The new improved model is compared with previous models described in the literature. It will be especially useful for short-term studies of subglottic or tracheal stenosis.

The diagnosis of low-grade dysplasia in Barrett's esophagus and its implications for disease progression.

OBJECTIVE: The reported risk of progression from low-grade dysplasia (LGD) to high-grade dysplasia (HGD) or carcinoma (CA) in Barrett's esophagus varies. However, the validity of a diagnosis of LGD may be questioned because of interobserver variability. METHODS: A search of the Cleveland Clinic Foundation surgical pathology files between 1986 and 1997 yielded biopsy specimens from 43 patients with Barrett's esophagus diagnosed and coded as LGD. Patients with concurrent or prior diagnoses of HGD or carcinoma were excluded. The LGD cases were randomized and blindly reviewed by three gastrointestinal (GI) pathologists along with cases originally diagnosed as Barrett's esophagus without dysplasia (ND; n = 28), indefinite for dysplasia (IND; n = 14), or HGD (n = 15). Each pathologist classified every biopsy specimen as ND, IND, LGD, or HGD, and interobserver agreements were determined by kappa statistics (K). Follow-up data were available on 25 patients originally diagnosed with LGD. Progression was defined as a subsequent diagnosis of HGD or CA on esophageal biopsy or resection specimens. RESULTS: Agreement between two GI pathologists for a diagnosis of LGD was fair (K = 0.28) and poor (K = 0.21 and -0.04). Individual GI pathologists agreed with the original diagnosis of LGD in 70%, 56%, and 16% of cases. The 25 patients with follow-up included 21 men and four women (mean age, 67 yr) with a mean follow-up of 26 months (range: 2-84 months). Seven patients (28%) with follow-up developed HGD (five patients) or CA (two patients), 2-43 months (median: 11 months) after a diagnosis of LGD. The individual GI pathologists' diagnosis did not correlate with progression. However, when at least two GI pathologists agreed on LGD, there was a significant association with progression (seven of 17 patients, 41%, p = 0.04). When all three GI pathologists agreed on a diagnosis of LGD, four of five patients progressed (p = 0.012). In contrast, of the eight patients with follow-up and no agreement among GI pathologists for a diagnosis of LGD, none progressed. CONCLUSIONS: A high degree of interobserver variability is seen in the histological diagnosis of Barrett's esophagus-related LGD. Although the number of observations is low, a consensus diagnosis of LGD among GI pathologists suggests an increased risk of progression from LGD to HGD or carcinoma.