Predictors of progression to cancer in Barrett's esophagus: baseline histology and flow cytometry identify low- and high-risk patient subsets

Dysplasia in Barrett's esophagus: limitations of current management strategies

Dysplasia is a very imperfect biomarker for malignancy in Barrett's esophagus. Invasive cancer has been found in 30-40% of esophagi resected because preoperative endoscopic examinations had shown high-grade dysplasia. Reports on the natural history of this disorder are sometimes contradictory, but suggest that 10-30% of patients with high-grade dysplasia in Barrett's esophagus will develop a demonstrable malignancy within 5 yr of the initial diagnosis. Proposed management strategies for high-grade dysplasia include esophagectomy, endoscopic ablative therapies, endoscopic mucosal resection (EMR), and intensive endoscopic surveillance. Endoscopic ablative therapies and EMR may not be effective if neoplastic cells have invaded the submucosa or disseminated through mucosal lymphatic channels, and a number of studies suggest that the endoscopic therapies usually leave metaplastic or neoplastic epithelium with malignant potential behind. Limited data suggest that intensive endoscopic surveillance might be a reasonable approach for elderly or infirm patients, but some patients managed in this fashion have developed incurable esophageal cancers. The fundamental question of what is the appropriate length of follow-up for studies on dysplasia treatments has not been resolved. Although 5 yr might be considered the absolute minimum duration for a meaningful follow-up on dysplasia therapy, the follow-up duration in most studies is substantially less than 5 yr. Specific recommendations for management based on these considerations are proposed at the end of this report.

Dysplasia and risk of further neoplastic progression in a regional Veterans Administration Barrett's cohort

OBJECTIVES

No published data are available on the risk of further neoplastic progression in Barrett's patients stratified by baseline dysplasia status. Our aims were to estimate and compare the risk of progression to high-grade dysplasia or cancer in groups of Barrett's patients stratified by baseline dysplasia status.

METHODS

Consecutive Barrett's cases from 1988-2002 were identified via pathology databases in a regional VA health-care system and medical record data were abstracted. The risk of progression to high-grade dysplasia or cancer was measured and compared in cases with versus without low-grade dysplasia within 1 yr of index endoscopy using survival analysis.

RESULTS

A total of 575 Barrett's cases had 2,775 patient-years of follow-up. There were 13 incident cases of high-grade dysplasia and two of cancer. The crude rate of high-grade dysplasia or cancer was 1 of 78 patient-years for those with baseline dysplasia versus 1 of 278 patient-years for those without (p= 0.001). One case of high-grade dysplasia in each group underwent successful therapy. One incident cancer case underwent successful resection and the other was unresectable. Two cases with high-grade dysplasia later developed cancer, one died postoperatively, the other was unresectable. When these two cases were included (total of four cancers), the crude rate of cancer was 1 of 274 patient-years for those with baseline dysplasia versus 1 of 1,114 patient-years for those without.

CONCLUSIONS

In a large cohort study of Barrett's, incident malignancy was uncommon. The rate of progression to high-grade dysplasia or cancer was significantly higher in those with baseline low-grade dysplasia. These data may warrant reevaluation of current Barrett's surveillance strategies.

Are screening and surveillance for Barrett's oesophagus really worthwhile?

Oesophageal adenocarcinoma has a low incidence and still remains an uncommon cancer; however, it has been on the rise over the past 20 years. Barrett's oesophagus, a complication of gastro-oesophageal reflux disease, is the only known precursor of this adenocarcinoma. It can often be asymptomatic and probably goes undiagnosed in the majority of the population. There are no direct data supporting the practice of screening for Barrett's oesophagus and oesophageal adenocarcinoma among the general population or even in patients with chronic reflux symptoms. However, many argue that the detection of neoplasms at a curable state in a high risk population can perhaps justify screening endoscopy. No prospective, controlled trials have been conducted to support the effectiveness of surveillance, but some indirect evidence does exist. The cost effectiveness of surveillance programmes needs to be further assessed in prospective studies. Ultimately, the use of better tools to diagnose Barrett's oesophagus and dysplasia and the identification of high risk groups for progression to oesophageal adenocarcinoma could potentially make screening and surveillance a cost effective practice.

Barrett's oesophagus: from metaplasia to dysplasia and cancer

Barrett's oesophagus is a premalignant condition that predisposes to the development of oesophageal adenocarcinoma. It is detected on endoscopy and confirmed histologically by the presence in the lower oesophagus of a metaplastic mucosa, the so-called specialised epithelium, which resembles incomplete intestinal metaplasia in the stomach. These similarities with incomplete intestinal metaplasia are present on histology, mucin histochemistry, and immunohistochemistry with various differentiation markers (cytokeratins and MUC antigens). On morphology, the carcinogenetic process of Barrett's mucosa progresses through increasing grades of epithelial dysplasia. Dysplasia, a synonym of intraepithelial neoplasia, is the only marker that can be used at the present time to delineate a population of patients at high risk of cancer. Among the numerous molecular events that have been shown to play a role in the neoplastic transformation of Barrett's mucosa, only changes in DNA ploidy, increased proliferation, and alterations of the p53 gene have been suggested to be of potential help in the surveillance of patients.

What is the best management strategy for high grade dysplasia in Barrett's oesophagus? A cost effectiveness analysis

BACKGROUND

Multiple treatment strategies for subjects with high grade dysplasia (HGD) in Barrett's oesophagus (BO) have been suggested. However, it is unclear which of these strategies provides the greatest life expectancy, and the costs associated with the management strategies are unknown.

AIM

To compare the efficacy and cost effectiveness of competing management strategies for BO with HGD.

METHODS

We created a decision analysis model in Data 4.0 to assess possible treatment strategies for BO with HGD. The strategies included: (1) no preventative strategy, (2) elective surgical oesophagectomy, (3) endoscopic ablation, and (4) surveillance endoscopy. The base case was a healthy 50 year old White male with an initial diagnosis of BO with HGD. The model allowed for complications of surgery, including death. Ablative therapy could cause stricture or perforation. Pathological misinterpretation was allowed, and modelled after reported rates. Estimates were derived from the literature for the rate of progression of HGD to cancer and for complication rates for the various treatment modalities. The endoscopic ablation arm was modelled as photodynamic therapy. Sensitivity analyses were performed over a wide range of cancer incidences, complication rates, and procedure costs.

RESULTS

Endoscopic ablation was the most effective strategy, yielding 15.5 discounted quality adjusted life years (dQALY), compared with 15.0 for endoscopic surveillance and 14.9 for oesophagectomy. No preventative strategy was the most inexpensive option, yielding an average cost per quality adjusted life year of US dollars 54 (44) per dQALY, but resulted in high rates of cancer. Endoscopic surveillance dominated oesophagectomy, being both less costly and more effective. The condition of extended dominance occurred when comparing endoscopic ablation to endoscopic surveillance because, although the total costs of ablation were greater than those of surveillance, it was less expensive to buy an additional life year using endoscopic ablation than endoscopic surveillance. The incremental cost effectiveness ratio when moving from no therapy to ablative therapy was a reasonable US dollars 25 621/dQALY (21 009/dQALY). Sensitivity analysis demonstrated that when yearly rates of progression to cancer from HGD exceeded 30%, oesophagectomy became the most cost effective option.

CONCLUSIONS

A strategy of endoscopic ablation provided the longest quality adjusted life expectancy for BO with HGD. Although endoscopic surveillance was less expensive than endoscopic ablation, it was associated with shorter survival. Optimal utilisation of healthcare resources may be achieved with endoscopic ablative therapy for BO with HGD.

DNA abnormalities as marker of risk for progression of Barrett's esophagus to adenocarcinoma: image cytometric DNA analysis in formalin-fixed tissues

OBJECTIVES

To examine DNA content abnormalities in patients with Barrett's esophagus (BE) who progress to esophageal adenocarcinoma, using image cytometric DNA analysis (ICDA) of formalin-fixed tissues.

METHODS

Studies were performed on archived biopsies of BE patients' undergoing endoscopic surveillance before developing adenocarcinoma. A comparison group consisted of BE patients' free of cancer during a follow-up period of over 9 yr. Tissue sections were analyzed for the degree of dysplasia and for DNA content abnormalities, using image cytometry. Additional patients were also analyzed in a cross-sectional study of 56 BE cases with and without dysplasia, including 12 cases of adenocarcinoma.

RESULTS

Five patients developed adenocarcinoma during follow-up and earlier biopsies obtained before cancer diagnosis showed specialized intestinal metaplasia (SIM) followed by low-grade dysplasia (LGD) in one, SIM followed by high-grade dysplasia (HGD) in one, LGD in two, and HGD in one case. All five showed some DNA abnormality at baseline or in interval biopsies. In the comparison group, five of seven patients showed normal diploid DNA at baseline and on follow-up biopsies. One patient initially had diploid DNA, but developed aneuploidy 11 yr later. Another case initially had aneuploidy, but was diploid on follow-up. Overall, DNA abnormalities were found in 13% of cases with SIM without dysplasia, 60% with LGD, 73% with HGD, and 100% with adenocarcinoma.

CONCLUSIONS

(i) Image cytometric DNA analysis is a useful method to examine DNA abnormalities in formalin-fixed tissues and may be more sensitive in predicting progression to adenocarcinoma than HGD. (ii) Histological dysplasia of any grade and DNA abnormalities, help identify BE patients at high risk for adenocarcinoma.

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Risk stratification of Barrett's esophagus: updated prospective multivariate analysis

OBJECTIVES

Prospective evaluation of Barrett's esophagus (BE) in order to determine what demographic, endoscopic, and histologic features are predictive of the prevalence and incidence of Barrett's high-grade dysplasia (HGD) and adenocarcinoma (Ca).

METHODS

Newly diagnosed BE patients were entered into and followed in a standardized surveillance protocol. The following features were examined using either forward, stepwise multiple regression analysis, or Cox proportional hazards to determine their ability to predict the presence of HGD or Ca at index BE diagnosis as well as their ability to predict progression of BE during follow-up: age, race, gender, length of BE in cm, size of a hiatal hernia, severity of dysplasia at index diagnosis as well as during surveillance, gastric Helicobacter pylori infection status, and type of medical acid-reflux treatment.

RESULTS

A total of 550 patients were diagnosed with BE over the study period. Stepwise multiple regression analysis showed three factors significantly associated with index diagnosis of HGD or Ca: hiatal hernia (larger size), Barrett's length (longer length), and absence of H. pylori infection. Three hundred and twenty-four BE entered the surveillance protocol. Cox proportional hazards models revealed a significant and independent association for five factors predictive of the time to progression of BE: presence of dysplasia at index diagnosis (p < 0.001), severity of dysplasia during surveillance (p < 0.001), length of Barrett's epithelium (p= 0.012), size of hiatal hernia (p= 0.006), and gastric H. pylori infection status (p= 0.023).

CONCLUSIONS

Endoscopic and histologic features of BE at initial diagnosis are predictive of index HGD and cancer as well as with risk of BE progression.

Multiple management modalities in esophageal cancer: epidemiology, presentation and progression, work-up, and surgical approaches

Annually, approximately 13,200 people in the U.S. are diagnosed with esophageal cancer and 12,500 die of this malignancy. Of new cases, 9,900 occur in men and 3,300 occur in women. In part I of this two-part series, we explore the epidemiology, presentation and progression, work-up, and surgical approaches for esophageal cancer. In the 1960s, squamous cell cancers made up greater than 90% of all esophageal tumors. The incidence of esophageal adenocarcinomas has risen considerably over the past two decades, such that they are now more prevalent than squamous cell cancer in the western hemisphere. Despite advances in therapeutic modalities for this disease, half the patients are incurable at presentation, and overall survival after diagnosis is grim. Evolving knowledge regarding the etiology of esophageal carcinoma may lead to better preventive methods and treatment options for early stage superficial cancers of the esophagus. The use of endoscopic ultrasound and the developing role of positron emission tomography have led to better diagnostic accuracy in this disease. For years, the standard of care for esophageal cancer has been surgery; there are several variants of the surgical approach. We will discuss combined modality approaches in part II of this series.

Zoning of mucosal phenotype, dysplasia, and telomerase activity measured by telomerase repeat assay protocol in Barrett's esophagus

Glandular dysplasia in Barrett's esophagus may regress spontaneously but can also progress to cancer. The human telomerase RNA template and the human telomerase reverse transcriptase enzyme which do not, of themselves, correlate strongly with telomerase activity, are too often overexpressed in Barrett's dysplasia to predict individual cancer risk. This study relates telomerase activity, mucosal phenotype, and dysplasia in Barrett's esophagus. Biopsies (n = 256) from squamous esophagus, columnar-lined esophagus every 2 cm, esophago-gastric junction, gastric body, and antrum from 32 patients with long-segment Barrett's esophagus were evaluated by telomerase repeat assay protocol (TRAP). Three biopsies for histology (n = 794) were simultaneously taken at each anatomical level. These and all prior and subsequent biopsies (n = 1917) were reviewed for mucosal phenotypes and dysplasia severity. Intestinal-type Barrett's mucosa was present at all levels in Barrett's esophagus. At least one Barrett's biopsy was TRAP(+) in 22 of 32 patients. TRAP positivity of intestinal-type Barrett's mucosa increased distally, possibly as a consequence of mucosal exposure to acid or bile reflux. Native gastric mucosa was rarely TRAP(+) (1/31 corpus, 2/32 antrum), whereas native squamous mucosa usually was TRAP(+) (31/32). Dysplasia almost always involved intestinal-type Barrett's mucosa (85/87; P <.00001), without evidence of proximal-distal zoning. TRAP could be positive without dysplasia and negative in extensive, even high-grade, dysplasia. TRAP activity merits evaluation as a candidate biomarker for increased risk of persistent dysplasia and cancer progression in Barrett's esophagus.

Approach to early Barrett's cancer

Because of effective surveillance programs in patients with known Barrett's esophagus, adenocarcinoma of the distal esophagus is increasingly diagnosed at early stages. With the introduction of limited surgical and endoscopic treatment modalities, the need for radical esophagectomy and extensive lymphadenectomy in such patients has been questioned. When selecting the approach to early Barrett's cancer, the precancerous nature of the underlying Barrett's esophagus, the frequent multicentricity of neoplastic alterations within the Barrett mucosa, the inaccuracy of current staging modalities, and the presence of lymph node metastases should be taken into account. Invasiveness and morbidity of the procedures, as well as quality of life aspects, should also be considered. From an oncologic point of view the minimum extent of a resection for early Barrett's cancer should include a full-thickness removal of the entire segment of the distal esophagus covered by intestinal metaplasia together with a regional lymphadenectomy. In appropriately selected patients this can be achieved by a limited surgical procedure involving transhiatal resection of the distal esophagus, but not by endoscopic mucosal ablation or endoscopic mucosa resection. Our experience with 49 limited surgical resections with regional lymphadenectomy indicates that this procedure is oncologically adequate and safe. Reconstruction with an interposed jejunal loop prevents postoperative gastroesophageal reflux and is associated with good quality of life. In contrast, endoscopic interventions are plagued by a high tumor recurrence rate, probably from persistence of Barrett's mucosa and gastroesophageal reflux.

Long-term endoscopic surveillance of patients with Barrett's esophagus. Incidence of dysplasia and adenocarcinoma: a prospective study

OBJECTIVE

Barrett's esophagus (BE) is a premalignant condition for which regular endoscopic follow-up is usually advised. We evaluated the incidence of esophageal adenocarcinoma (AC) in patients with BE and the impact of endoscopic surveillance on mortality from AC.

METHODS

A cohort of newly diagnosed BE patients was studied prospectively. Endoscopic and histological surveillance was recommended every 2 yr. Follow-up status was determined from hospital and registry office records and telephone calls to the patients.

RESULTS

From 1987 to 1997, BE was diagnosed in 177 patients. We excluded three with high-grade dysplasia (HGD) at the time of enrollment. Follow-up was complete in 166 patients (135 male, 31 female). The mean length of endoscopic follow-up was 5.5 yr (range 0.5-13.3). Low-grade dysplasia (LGD) was present initially in 16 patients (9.6%) and found during follow-up in another 24 patients. However, in 75% of cases, LGD was not confirmed on later biopsies. HGD was found during surveillance in three patients (1.8%), one with simultaneous AC; two with HGD developed AC later. AC was detected in five male patients during surveillance. The incidence of AC was 1/220 (5/1100) patient-years of total follow-up, or 1/183.6 (5/918) patient-years in subjects undergoing endoscopy. Four AC patients died, and one was alive with advanced-stage tumor. The mean number of endoscopies performed for surveillance, rather than for symptoms, was 2.4 (range 1-10) per patient. During the follow-up years the cohort had a total of 528 examinations and more than 4000 biopsies.

CONCLUSIONS

The incidence of AC in BE is low, confirming recent data from the literature reporting an overestimation of cancer risk in these patients. In our patient cohort, surveillance involved a large expenditure of effort but did not prevent any cancer deaths. The benefit of surveillance remains uncertain.

Extended lifespan of Barrett's esophagus epithelium transduced with the human telomerase catalytic subunit: a useful in vitro model

As there has been no previous information on the consequences of telomerase expression in genetically altered, mortal cells derived from pre-malignant tissue, we sought to determine the effect of hTERT (human catalytic subunit of telomerase reverse transcriptase) transduction of pre-malignant cell strains from Barrett's esophagus that do not contain telomerase activity and possess a finite lifespan. Primary cultures of Barrett's esophageal epithelium transduced with a retrovirus containing hTERT were characterized by growth factor requirements, cytogenetics and flow cytometry. Expression of telomerase lengthened telomeres and greatly extended the lifespan of hTERT transduced (hTERT+) Barrett's esophagus cells. Growth factor dependency of the hTERT+ cultures remained largely similar to the parental cultures, although there was a modest increase in the ability to grow in agar. Chromosomal instability, measured by both karyotypic and FISH (fluorescence in situ hybridization) analyses, was reduced but not abrogated by hTERT transduction, suggesting that telomerase expression can enhance genomic stability. However, the persistence of residual instability gave rise to new clonal and non-clonal genetic variants, and in one hTERT+ culture a new DNA aneuploid population was observed, the only time such a ploidy shift has been seen in Barrett's cell strains in vitro. These in vitro observations are analogous to the clinical progression to aneuploidy that often precedes cancer in Barrett's esophagus, and suggest that reactivation of telomerase may be permissive for continued genetic evolution to cancer. Long-lived Barrett's esophagus epithelial cultures should provide a useful in vitro model for studies of neoplastic evolution and chemopreventive therapies.

Serum selenium levels in relation to markers of neoplastic progression among persons with Barrett's esophagus

BACKGROUND

Persons with Barrett's esophagus have a substantially greater risk of esophageal adenocarcinoma than the general population. Higher serum selenium levels have been associated with a reduced risk of several cancers; however, their association with the risk of esophageal adenocarcinoma is unknown. We used a cross-sectional study to investigate the relationship between serum selenium levels and markers of neoplastic progression among persons with Barrett's esophagus.

METHODS

Medical history, blood, and esophageal tissue specimens were collected from 399 members of a cohort study of Barrett's esophagus patients undergoing endoscopic surveillance. Serum selenium levels were measured by flameless atomic absorption spectrophotometry. DNA content of tissue samples was measured by flow cytometry. Loss of heterozygosity (LOH) at 9p and 17p, chromosomal regions which include the p16 and p53 tumor suppressors, respectively, was detected by automated fluorescent genotyping. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). All statistical tests were two-sided.

RESULTS

Persons with serum selenium levels in the upper three quartiles (i.e., >1.5 micro M) were less likely to have high-grade dysplasia (OR = 0.5, 95% CI = 0.3 to 0.9) or aneuploidy (OR = 0.4, 95% CI = 0.2 to 0.8) than those with levels in the lowest quartile. Serum selenium levels in the upper three quartiles were associated with similar reductions in risk of 17p (p53) LOH (OR = 0.5, 95% CI = 0.2 to 0.9) and increased 4N fraction (OR = 0.6, 95% CI = 0.3 to 1.2). By contrast, serum selenium levels were not associated with 9p (p16) LOH (OR = 1.0, 95% CI = 0.5 to 1.7), a marker that appears early in neoplastic progression.

CONCLUSION

Our preliminary results, from a cross-sectional analysis with biologic markers, suggest that higher serum selenium levels may be associated with a reduced risk of esophageal adenocarcinoma among persons with Barrett's esophagus. Because serum selenium was not associated with 9p (p16) LOH, we speculate that selenium may act primarily at later stages of progression toward adenocarcinoma.

Barrett's esophagus and Barrett's carcinoma

The alarming rise in the incidence of esophageal adenocarcinomas in the Western world has focused interest on so-called Barrett's esophagus. Barrett's esophagus is characterized by specialized intestinal epithelium replacing the normal squamous epithelium in the distal esophagus and is considered a consequence of long-lasting and severe gastroesophageal reflux disease. A metaplasia-dysplasia-carcinoma sequence links Barrett's esophagus with adenocarcinoma of the distal esophagus (Barrett's cancer). Despite intensive research, many questions concerning the pathogenesis, diagnosis, and treatment of Barrett's esophagus and associated adenocarcinoma are still unanswered. Based on current data, the malignant progression of Barrett's esophagus cannot be substantially prevented by medical or surgical therapy for reflux. Although no firm data are available to show that surveillance strategies can reduce overall mortality from Barrett's cancer, early detection and cure are possible. Management of Barrett's esophagus and carcinoma is reviewed with reference to the sequence of disease from metaplasia to carcinoma.

Chromosome 4 hyperploidy represents an early genetic aberration in premalignant Barrett's oesophagus

BACKGROUND AND AIMS

Characterisation of the underlying molecular mechanisms that promote Barrett's progression may ultimately lead to identification of potential predictive genetic markers that classify patients' malignant risk. In an attempt to understand these causative pathways, fluorescence in situ hybridisation (FISH) was used in this study to determine when specific genetic alterations arise during Barrett's associated neoplastic progression.

METHODS

Endoscopic cytology brushings were obtained from 28 patients with Barrett's metaplasia, 28 with dysplasia (20 low grade dysplasia (LGD) and eight with high grade dysplasia (HGD)), and seven with adenocarcinoma, together with paired control brushings from regions of normal proximal squamous cell epithelium. The exfoliated epithelial cells were washed and deposited onto slides. Probes specific for the centromeres of chromosomes 4, 8, 20, and Y, and locus specific probes for the tumour suppressor genes p16, p53, and Rb were subsequently hybridised.

RESULTS

Aneuploidy was found early in progression, with metaplastic tissues displaying increased copy numbers of chromosomes 4 and 8. Chromosome 4 hyperploidy was found in 89%, 90%, 88%, and 100% of metaplasias, LGD, HGD, adenocarcinomas, respectively, while chromosome 8 hyperploidy occurred in 71%, 75%, 100%, and 100% of patients with the respective staging. Loss of the p16 tumour suppressor gene also presented in metaplastic epithelium (7%) but most other genetic aberrations were only seen in HGD.

CONCLUSIONS

Genetic instability arises well before dysplasia in Barrett's oesophagus, with chromosome 4 and 8 hyperploidy representing the earliest and most common alterations identified. As these aberrations are widespread at all the premalignant stages, there may be genes on chromosomes 4 and 8 that are involved in both the initiation and progression of Barrett's oesophagus.

Molecular markers and staging of early esophageal cancer

BACKGROUND

Patients with early esophageal cancer experience varying clinical outcomes despite identical tumor staging by standard diagnostic methods because clinical and histopathological staging fail to reveal the underlying complex biology of cancer.

METHODS AND FOCUS

This review discusses some of the current concepts of molecular staging with the potential to enhance the current staging methods of patients with early esophageal cancer.

CONCLUSIONS

Understanding the molecular biology of esophageal cancer has increased substantially, and clinicians anticipate the translation of the gained knowledge into patient care. Numerous molecular techniques are potentially available for analyzing biological aspects of the individual tumor for improved staging.

Can extent of high grade dysplasia in Barrett's oesophagus predict the presence of adenocarcinoma at oesophagectomy?

BACKGROUND

Optimal management of Barrett's oesophagus complicated by high grade dysplasia is controversial. Recently, the extent of high grade dysplasia was described as a predictor of subsequent development of cancer in patients undergoing continued surveillance. However, there is no universal agreement on the definition of extent of high grade dysplasia.

AIM

To determine if extent of high grade dysplasia in Barrett's oesophagus is a predictor of the presence of adenocarcinoma at the time of oesophagectomy.

METHODS

Forty two patients with Barrett's oesophagus and high grade dysplasia who underwent oesophagectomy between 1985 and 1999 were identified from a prospective database. All pathological specimens, including preoperative endoscopic biopsies and post-oesophagectomy sections, were reviewed in a blinded fashion by one expert gastrointestinal pathologist to determine the extent of high grade dysplasia. The extent of high grade dysplasia was defined using two different criteria, one from the Cleveland Clinic and one from the Mayo Clinic.

RESULTS

Twenty four of 42 patients (57%) had unsuspected cancer at the time of oesophagectomy. Using the Cleveland Clinic definition, 10 of 21 (48%) patients with focal high grade dysplasia had carcinoma compared with 14 of 21 patients (67%) with diffuse high grade dysplasia (p=0.35). Using the Mayo Clinic definition, adenocarcinoma was found in five of seven (72%) patients with focal high grade dysplasia compared with 19 of 35 (54%) with diffuse high grade dysplasia (p=0.68).

CONCLUSIONS

The extent of high grade dysplasia, regardless of how it is defined, does not predict the presence of unsuspected adenocarcinoma at oesophagectomy. There is no evidence as yet that the extent of high grade dysplasia can be used as a basis for decision making in these patients.

Barrett's esophagus with high grade dysplasia: surgical results and long-term outcome--an update

We updated our surgical results and long-term outcome for prophylactic esophagectomy in patients with Barrett's esophagus and high-grade dysplasia (HGD) and determined the incidence of occult adenocarcinoma. Sixty consecutive patients with HGD who underwent esophagectomy had pre- and postoperative pathology examined at our institution from 1982 to 2001. We reviewed medical records to determine patient characteristics, surgical approach, operative morbidity and mortality, pathology, and length of stay. Patients and/or referring physicians were contacted to determine long-term outcome. Fifty-three men (88%) and 7 women (12%) were followed up for a median of 4.6 years. Transhiatal esophagectomy was performed in the majority of patients (82%). There was one operative death (1.7%) and 15 complications (29%). Median length of stay was 9 days. In 18 patients (30%), invasive adenocarcinoma was detected in the resected specimen. When examined by time periods, 43% (13/30) of patients were diagnosed with occult cancer from 1982-1994, whereas 17% (5/30) harbored occult malignancy from 1994-2001. All patients with adenocarcinoma in the recent interval had stage I disease, as opposed to only 61.5% of patients from the earlier study. Operative mortality declined from 3.3% to 0% over the two intervals as did mean length of stay from 14 days to 10 days. Five-year survival was excellent at 88%. Age and amount of preoperative weight loss were preoperative predictors of survival, whereas major postoperative complications and stage were postoperative predictors of outcome. Barrett's esophagus with high-grade dysplasia continues to be an indication for prophylactic esophagectomy. Overall prevalence of occult adenocarcinoma remains high. We have demonstrated a declining incidence of occult cancer and treatment of earlier stage adenocarcinoma when found in this population of patients treated with esophagectomy.

Neodymium:yttrium-aluminum garnet contact laser ablation of Barrett's high grade dysplasia and early adenocarcinoma

OBJECTIVES

We describe the efficacy and safety of neodymium:yttrium-aluminum garnet (Nd:YAG) contact laser ablation of Barrett's high grade dysplasia (HGD) and/or early adenocarcinoma.

METHODS

Consecutive Barrett's patients in whom HGD or adenocarcinoma was detected were eligible. Radial array echoendosonography and high frequency catheter probe ultrasonography were performed. Patients were excluded if ultrasound revealed the presence of Barrett's cancer with regional lymph nodes or celiac trunk metastases or extension of the tumor into superficial submucosa (T1sm1) or greater. Nd:YAG laser used quartz contact probes, with all Barrett's epithelium targeted at each session. Complete ablation was confirmed with Lugol's iodine chromoendoscopy followed by surveillance biopsies of the neosquamous epithelium. Adverse events were ascertained by scheduled telephone contact interviews.

RESULTS

A total of 36 patients with HGD/adenocarcinoma were evaluated at our center, 17 of whom met all inclusion criteria. Of the patients, 14 have remained in the study, and all have had successful elimination of HGD and cancer. In addition, 11 patients (78.6%) achieved complete endoscopic and histological ablation of all Barrett's tissue. Two patients (14.3%) achieved 95% destruction of Barrett's with residual metaplastic columnar epithelium containing goblet cells without dysplasia. The remaining patient has obtained 75% ablation of Barrett's, with residual metaplastic columnar epithelium harboring Barrett's with low grade dysplasia. Major complications included two esophageal strictures (11.8%) and one mild upper GI bleed (5.9%).

CONCLUSIONS

This preliminary experience with Nd:YAG contact laser for the treatment of Barrett's HGD and early superficial cancers seems promising. The need for additional controlled trials with larger numbers of patients with longer follow-up, as well as consideration of a head-to-head trial with Photofrin photodynamic therapy, is warranted.

Upper endoscopy as a screening and surveillance tool in esophageal adenocarcinoma: a review of the evidence

Esophageal adenocarcinoma is a rare cancer that is increasing rapidly in incidence. Because gastroesophageal reflux disease (GERD) is a risk factor for the development of this cancer, endoscopic screening of individuals with GERD symptoms and endoscopic surveillance of those who are found to have Barrett's esophagus (BE), the presumed precursor to adenocarcinoma, have been proposed. Although no direct data support endoscopic screening or surveillance, several lines of indirect evidence are available. We apply a set of criteria for the evaluation of screening programs to endoscopic screening of subjects with reflux and endoscopic surveillance of subjects with BE. A critical examination of the data supporting these practices shows that considerable gaps exist in our knowledge regarding endoscopy as a screening test in GERD, making us unable to support this practice based on current evidence. Although no controlled trials exist to substantiate the effectiveness of surveillance programs for subjects with BE, some stronger indirect evidence does support this practice. However, further studies are necessary to substantiate the effectiveness and cost-effectiveness of endoscopic surveillance in BE. Based on the currently available data, consideration should be given to expanding the intervals between endoscopic surveillance sessions.

Surveillance in Barrett's oesophagus: a personal view

Barrett's oesophagus is defined as columnar-lined oesophagus of any length containing specialised intestinal metaplasia. Diagnosis depends on close corroboration between the endoscopist and histopathologist. It occurs in 10% of patients presenting endoscopically with reflux symptoms and has an adenocarcinoma incidence of 0.4% to 2%. Surveillance is performed to detect precancerous change (dysplasia) and early stage disease has a good surgical prognosis. Computer models suggest cost efficacy comparable to other health measures. However most patients with Barrett's do not die of oesophageal cancer and elective oesophagectomy has an appreciable mortality. Endoscopic ablation techniques and improved definition of high risk subgroups will help shape future surveillance programmes.

Are ulcers a marker for invasive carcinoma in Barrett's esophagus? Data from a diagnostic variability study with clinical follow-up

OBJECTIVES

We correlated follow-up information from 138 patients with Barrett's esophagus and varying degrees of dysplasia with the presence of ulcers.

METHODS

A group of pathologist participants were asked to contribute patients' initial biopsy slides showing Barrett's esophagus (BE) without dysplasia and with epithelial changes indefinite for dysplasia, low grade dysplasia (LGD), high grade dysplasia (HGD), and adenocarcinoma. From the initial 250 cases used for a diagnostic reproducibility study, follow-up information was available for 138 patients.

RESULTS

There were 44 cases submitted as BE, 22 as BE with epithelial changes indefinite for dysplasia, 26 as BE with LGD, 33 as BE with HGD, and 13 as BE with adenocarcinoma. Ulcers were present in 35/138 cases (25%), including 3/44 cases of BE without dysplasia (7%), 2/22 cases of BE with epithelial changes indefinite for dysplasia (9%), 0/26 cases of BE with LGD (0%), 10/33 cases of BE with HGD (30%), and 7/13 cases of BE with adenocarcinoma (54%). On follow-up, there were no invasive carcinomas detected among the BE without dysplasia group (median follow-up = 38.5 months). Adenocarcinomas were detected in 4/22 cases (18%) submitted as BE with epithelial changes indefinite for dysplasia at 19, 55, 60, and 62 months and in 4/26 cases (15%) of BE with LGD at 9, 9, 11, and 60 months. None of these carcinomas occurred in cases in which an ulcer was present in the initial biopsy specimen. Among the 33 HGD cases, 20 (60%) were found to have adenocarcinoma on subsequent resection specimens. The presence of an ulcer with HGD increased the likelihood of finding carcinoma in the resection specimen, as 8/10 biopsies (80%) of HGD patients with ulcers had carcinoma, compared to 12/23 biopsies (52%) of HGD patients without ulcers. All of the cases interpreted as adenocarcinomas on biopsy were found either to have invasive carcinoma on esophageal resection or to have metastases that were demonstrated in unresectable patients.

CONCLUSION

If an ulcer accompanies HGD in a biopsy specimen from a patient with BE, it is likely that invasive carcinoma is also present at that time.

Long-term survival after esophagectomy for Barrett's adenocarcinoma in endoscopically surveyed and nonsurveyed patients

There is growing controversy over the cost-effectiveness of surveillance endoscopy for patients with Barrett's esophagus. A retrospective review was performed of 80 patients who underwent resection for Barrett's adenocarcinoma to assess the influence of endoscopic surveillance on long-term survival. Twelve patients initially were diagnosed with benign Barrett's esophagus and were followed with endoscopic surveillance. The remaining 68 patients had the diagnosis of Barrett's esophagus made at the time of their cancer diagnosis or resection. Patients in surveillance programs were younger (53 vs. 64 years; P = 0.008), had better performance status (8.9 vs. 8.2; P = 0.04), had less weight loss (0.3 vs. 5.5 kg; P < 0.001), had a similar incidence of gastroesophageal reflux disease symptoms (75% vs. 60%), and were less likely to undergo preoperative chemotherapy and/or radiation therapy (8% vs. 28%). Pathologic stage was 0 or I in 9 (75%) of 12 patients in the surveillance group compared to 12 (18%) of 68 of those in the no surveillance group (P < 0.001). Median survival for patients in the surveillance group was 107 months compared to 12 months for those in the no surveillance group (P < 0.001). Stratifying for stage, surveillance (hazard ratio = 3.05; confidence interval = 1.09 to 8.57; P = 0.034) was the only predictor of survival. Surveillance endoscopy permits early diagnosis of adenocarcinoma in patients with Barrett's esophagus and contributes substantially to long-term survival.

Predictors of progression in Barrett's esophagus III: baseline flow cytometric variables

OBJECTIVES

Barrett's esophagus develops in 5-10% of patients with gastroesophageal reflux disease and predisposes to esophageal adenocarcinoma. We have previously shown that a systematic baseline endoscopic biopsy protocol using flow cytometry with histology identifies subsets of patients with Barrett's esophagus at low and high risk for progression to cancer. In this report, we further examined cytometric variables to better define the characteristics that best enable DNA cytometry to help predict cancer outcome.

METHODS

Patients were prospectively evaluated using a systematic endoscopic biopsy protocol, with baseline histological and flow cytometric measurements as predictors and with cancer as the outcome.

RESULTS

A receiver operating curve analysis demonstrated that a 4N fraction cut point of 6% was optimal to discriminate cancer risk (relative risk [RR] = 11.7, 95% CI = 6.2-22). The 4N fractions of 6-15% were just as predictive of cancer as were fractions of >15%. We found that only aneuploid DNA contents of >2.7N were predictive of cancer (RR = 9.5, CI = 4.9-18), whereas those patients whose sole abnormality was an aneuploid population with DNA content of < or =2.7 had a low risk for progression. The presence of both 4N fraction of >6% and aneuploid DNA content of >2.7N was highly predictive of cancer (RR = 23, CI = 10-50). S phase was a predictor of cancer risk (RR = 2.3, CI = 1.2-4.4) but was not significant when high-grade dysplasia was accounted for.

CONCLUSIONS

Flow cytometry is a useful adjunct to histology in assessing cancer risk in patients with Barrett's esophagus. Careful examination of cytometric variables revealed a better definition of those parameters that are most closely associated with increased cancer risk.

Predictors of progression in Barrett's esophagus II: baseline 17p (p53) loss of heterozygosity identifies a patient subset at increased risk for neoplastic progression

OBJECTIVES

Most patients with Barrett's esophagus do not progress to cancer, but those who do seem to have markedly increased survival when cancers are detected at an early stage. Most surveillance programs are based on histological assessment of dysplasia, but dysplasia is subject to observer variation and transient diagnoses of dysplasia increase the cost of medical care. We have previously validated flow cytometric increased 4N fractions and aneuploidy as predictors of progression to cancer in Barrett's esophagus. However, multiple somatic genetic lesions develop during neoplastic progression in Barrett's esophagus, and it is likely that a panel of objective biomarkers will be required to manage the cancer risk optimally.

METHODS

We prospectively evaluated endoscopic biopsies from 325 patients with Barrett's esophagus, 269 of whom had one or more follow-up endoscopies, by a robust platform for loss of heterozygosity (LOH) analysis, using baseline 17p (p53) LOH as a predictor and increased 4N, aneuploidy, high-grade dysplasia, and esophageal adenocarcinoma as outcomes.

RESULTS

The prevalence of 17p (p53) LOH at baseline increased from 6% in negative for dysplasia to 57% in high-grade dysplasia (p < 0.001). Patients with 17p (p53) LOH had increased rates of progression to cancer (relative risk [RR] = 16, p < 0.001), high-grade dysplasia (RR = 3.6, p = 0.02), increased 4N (RR = 6.1, p < 0.001), and aneuploidy (RR = 7.5, p < 0.001).

CONCLUSIONS

Patients with 17p (p53) LOH are at increased risk for progression to esophageal adenocarcinoma as well as high-grade dysplasia, increased 4N, and aneuploidy. 17p (p53) LOH is a predictor of progression in Barrett's esophagus that can be combined with a panel of other validated biomarkers for risk assessment as well as intermediate endpoints in prevention trials.

Optimizing endoscopic biopsy detection of early cancers in Barrett's high-grade dysplasia

OBJECTIVE

The of high-grade dysplasia management (HGD) in Barrett's esophagus remains controversial, in part, because of uncertainty about the ability of endoscopic biopsies to consistently detect early, curable cancers.

METHODS

Here we report cancers we have diagnosed in 45 patients with Barrett's HGD using a protocol involving serial endoscopies with four-quadrant biopsies taken at 1-cm intervals. We compare these results to a modeled endoscopic biopsy protocol in which four-quadrant biopsies are taken every 2 cm in the Barrett's segment.

RESULTS

Thirteen cancers were detected at the baseline endoscopy and 32 in surveillance. In 82% of patients, cancer was detected at a single 1-cm level of the esophagus, and in 69% the cancer was detected in a single endoscopic biopsy specimen. A 2-cm protocol missed 50% of cancers that were detected by a 1-cm protocol in Barrett's segments 2 cm or more without visible lesions. The maximum depth of cancer invasion was intramucosal in 96% of patients. Only 39% of patients who had endoscopic biopsy cancer diagnoses had cancer detected in the esophagectomy specimen. Adverse outcomes included the development of regional metastatic disease during surveillance (1 of 32), operative mortality (3 of 36), including two patients who had their primary surgeries at other institutions, and death from metastatic disease after endoscopic ablation performed at another institution (1 of 3).

CONCLUSIONS

A four-quadrant, 1-cm endoscopic biopsy protocol performed at closely timed intervals consistently detects early cancers arising in HGD in Barrett's esophagus and should be used in patients with HGD who do not undergo surgical resection.