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1.
Gut ; 64(12): 1874-80, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25652086

RESUMO

OBJECTIVE: It is unclear whether Barrett's oesophagus (BO) length changes over time or whether the full length of the segment is established at the onset of disease recognition. The objectives of this study were to evaluate the association of age and BO length and to evaluate the changes in BO length over time. DESIGN: This is a prospective, multicentre cohort study involving patients with BO from five centres. Patients were divided into groups based on the decade of initial diagnosis of BO. The mean BO length and the mean change in BO length were calculated for each age decade. The mean change in BO length was also calculated between the index endoscopy and the last surveillance endoscopy. RESULTS: 3635 patients with BO were included in the study: 87.8% men, 92.8% Caucasians, mean age 60.9 years and mean BO length 3.5 cm. The mean change in BO length was 0.9 cm. The mean BO length did not significantly change for each age category: <30 years (4.6 cm), 30-39.9 years (3.2 cm), 40-49.9 years (3.1 cm), 50-59.9 years (3.1 cm), 60-69.9 years (3.6 cm), 70-79.7 (4.0 cm) and >80 years (4.5 cm), p=0.47. On subgroup analysis of patients with non-dysplastic BO who had at least 1 year of endoscopic follow up, there was a significant decrease in mean change in BO length across age categories ranging from +1.7 to -0.8 cm, p=0.03. CONCLUSIONS: There was no significant difference in BO length by age category in decades. In addition, the change in BO length from index to follow-up endoscopy was similar among patients >30 years. These findings suggest that a patient's BO segment length attains its full extent by the time of the initial endoscopic examination.


Assuntos
Esôfago de Barrett/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Esofagoscopia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
2.
Endoscopy ; 47(8): 669-74, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25910065

RESUMO

BACKGROUND AND STUDY AIM: Data are limited on the natural history of patients with Barrett's esophagus with a diagnosis of "indefinite for dysplasia" (IND). The aims of this study were to: (i) determine rates of progression to high grade dysplasia (HGD) or esophageal adenocarcinoma, and compare these with rates for low grade dysplasia (LGD); and (ii) determine the proportion of patients whose histological IND diagnosis changed on follow-up endoscopy. PATIENTS AND METHODS: Demographic, endoscopic, and histologic information of patients with diagnoses of IND and LGD and at least 12 months of follow-up were extracted from the database of a multicenter Barrett's esophagus study. Rates and times for progression to HGD and esophageal adenocarcinoma and regression to nondysplastic epithelium were calculated. Proportions of diagnoses upgraded to HGD/esophageal adenocarcinoma or downgraded to nondysplastic epithelium at first follow-up endoscopy were evaluated. RESULTS: Amongst 2264 patients, 83 with a diagnosis of IND (mean age 60 years, 95 % men, 95 % white; mean follow-up 5.6 years) and 79 with diagnosis of LGD were identified. In the IND group, annual incidences of esophageal adenocarcinoma and HGD were 0.21 % and 0.64 %, respectively, representing a combined incidence of 0.8 %. Mean time to progression was 4.72 years. Within the IND group 55 % patients showed regression to nondysplastic epithelium at first follow-up endoscopy and the overall regression rate was 80 %. Corresponding rates in LGD patients were similar. CONCLUSIONS: Lesions diagnosed as IND and LGD show similar biological behavior and can be treated as a single category with respect to surveillance and follow-up.


Assuntos
Esôfago de Barrett/complicações , Transtornos de Deglutição/diagnóstico , Endoscopia Gastrointestinal/métodos , Esôfago/patologia , Esôfago de Barrett/diagnóstico , Transtornos de Deglutição/epidemiologia , Transtornos de Deglutição/etiologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas , Fatores de Tempo , Estados Unidos/epidemiologia
3.
Gastroenterology ; 145(3): 548-53.e1, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23714382

RESUMO

BACKGROUND & AIMS: Recent population-based studies have shown a low risk of esophageal adenocarcinoma (EAC) in patients with nondysplastic Barrett's esophagus (NDBE). We evaluated whether persistence of NDBE over multiple consecutive surveillance endoscopic examinations could be used in risk stratification of patients with Barrett's esophagus (BE). METHODS: We performed a multicenter outcomes study of a large cohort of patients with BE. Based on the number of consecutive surveillance endoscopies showing NDBE, we identified 5 groups of patients. Patients in group 1 were found to have NDBE at their first esophagogastroduodenoscopy (EGD). Patients in group 2 were found to have NDBE on their first 2 consecutive EGDs. Similarly, patients in groups 3, 4, and 5 were found to have NDBE on 3, 4, and 5 consecutive surveillance EGDs. A logistic regression model was built to determine whether persistence of NDBE independently protected against development of cancer. RESULTS: Of a total of 3515 patients with BE, 1401 patients met the inclusion criteria (93.3% white; 87.5% men; median age, 60 ±17 years). The median follow-up period was 5 ± 3.9 years (7846 patient-years). The annual risk of EAC in groups 1 to 5 was 0.32%, 0.27%, 0.16%, 0.2%, and 0.11%, respectively (P for trend = .03). After adjusting for age, sex, and length of BE, persistence of NDBE, based on multiple surveillance endoscopies, was associated with a gradually lower likelihood of progression to EAC. CONCLUSIONS: Persistence of NDBE over several endoscopic examinations identifies patients who are at low risk for development of EAC. These findings support lengthening surveillance intervals or discontinuing surveillance of patients with persistent NDBE.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/patologia , Lesões Pré-Cancerosas/patologia , Idoso , Endoscopia do Sistema Digestório , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Risco
4.
Clin Gastroenterol Hepatol ; 11(11): 1430-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23707463

RESUMO

BACKGROUND & AIMS: It is not clear whether length of Barrett's esophagus (BE) is a risk factor for high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) in patients with nondysplastic BE. We studied the risk of progression to HGD or EAC in patients with nondysplastic BE, based on segment length. METHODS: We analyzed data from a large cohort of patients participating in the BE Study-a multicenter outcomes project comprising 5 US tertiary care referral centers. Histologic changes were graded as low-grade dysplasia, HGD, or EAC. The study included patients with BE of documented length without dysplasia and at least 1 year of follow-up evaluation (n = 1175; 88% male), and excluded patients who developed HGD or EAC within 1 year of their BE diagnosis. The mean follow-up period was 5.5 y (6463 patient-years). The annual risk of HGD and EAC was plotted in 3-cm increments (≤3 cm, 4-6 cm, 7-9 cm, 10-12 cm, and ≥13 cm). We calculated the association between time to progression and length of BE. RESULTS: The mean BE length was 3.6 cm; 44 patients developed HGD or EAC, with an annual incidence rate of 0.67%/y. Compared with nonprogressors, patients who developed HGD or EAC had longer BE segments (6.1 vs 3.5 cm; P < .001). Logistic regression analysis showed a 28% increase in risk of HGD or EAC for every 1-cm increase in BE length (P = .01). Patients with BE segment lengths of 3 cm or shorter took longer to develop HGD or EAC than those with lengths longer than 4 cm (6 vs 4 y; P = nonsignificant). CONCLUSIONS: In patients with BE without dysplasia, length of BE was associated with progression to HGD or EAC. The results support the development of a risk stratification scheme for these patients based on length of BE segment.


Assuntos
Adenocarcinoma/epidemiologia , Esôfago de Barrett/complicações , Esôfago de Barrett/patologia , Neoplasias Esofágicas/epidemiologia , Idoso , Feminino , Histocitoquímica , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Medição de Risco , Centros de Atenção Terciária , Estados Unidos
5.
N Engl J Med ; 360(22): 2277-88, 2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19474425

RESUMO

BACKGROUND: Barrett's esophagus, a condition of intestinal metaplasia of the esophagus, is associated with an increased risk of esophageal adenocarcinoma. We assessed whether endoscopic radiofrequency ablation could eradicate dysplastic Barrett's esophagus and decrease the rate of neoplastic progression. METHODS: In a multicenter, sham-controlled trial, we randomly assigned 127 patients with dysplastic Barrett's esophagus in a 2:1 ratio to receive either radiofrequency ablation (ablation group) or a sham procedure (control group). Randomization was stratified according to the grade of dysplasia and the length of Barrett's esophagus. Primary outcomes at 12 months included the complete eradication of dysplasia and intestinal metaplasia. RESULTS: In the intention-to-treat analyses, among patients with low-grade dysplasia, complete eradication of dysplasia occurred in 90.5% of those in the ablation group, as compared with 22.7% of those in the control group (P<0.001). Among patients with high-grade dysplasia, complete eradication occurred in 81.0% of those in the ablation group, as compared with 19.0% of those in the control group (P<0.001). Overall, 77.4% of patients in the ablation group had complete eradication of intestinal metaplasia, as compared with 2.3% of those in the control group (P<0.001). Patients in the ablation group had less disease progression (3.6% vs. 16.3%, P=0.03) and fewer cancers (1.2% vs. 9.3%, P=0.045). Patients reported having more chest pain after the ablation procedure than after the sham procedure. In the ablation group, one patient had upper gastrointestinal hemorrhage, and five patients (6.0%) had esophageal stricture. CONCLUSIONS: In patients with dysplastic Barrett's esophagus, radiofrequency ablation was associated with a high rate of complete eradication of both dysplasia and intestinal metaplasia and a reduced risk of disease progression. (ClinicalTrials.gov number, NCT00282672.)


Assuntos
Esôfago de Barrett/cirurgia , Ablação por Cateter , Esôfago/patologia , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/patologia , Ablação por Cateter/efeitos adversos , Progressão da Doença , Esôfago/cirurgia , Feminino , Humanos , Modelos Logísticos , Masculino , Metaplasia/cirurgia , Pessoa de Meia-Idade , Resultado do Tratamento
6.
Gastroenterology ; 141(4): 1179-86, 1186.e1, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21723218

RESUMO

BACKGROUND & AIMS: Data vary on the progression of low-grade dysplasia (LGD) in patients with Barrett's esophagus (BE); in patients with LGD, we investigated the incidence of high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) and compared progression in patients with different forms of LGD (prevalent vs incident and multifocal vs unifocal). We assessed the effects of consensus diagnosis of LGD on progression rates to HGD and EAC among expert pathologists. METHODS: In a multicenter outcomes project, 210 patients with BE and LGD (classified as incident, prevalent, or persistent) were included. Patients were followed up for an average of 6.2 years (959.6 patient-years). Persistent LGD was defined as detection of LGD on ≥2 consecutive occasions during the follow-up period and extent as either unifocal (LGD at one level of BE segment) or multifocal (>1 level). Histology specimens were reviewed by 2 blinded pathologists. RESULTS: Six patients developed EAC (incidence of 0.44%/year), and 21 developed HGD (incidence of 1.6%/year). The incidence of the combination of HGD and EAC was 1.83%/year. There were no associations between presence of prevalent, incident, or persistent LGD and the extent of LGD with progression rates. Based on consensus diagnosis of 88 reviewed specimens, there was no difference in the progression of LGD to either EAC (the incidence based on analyses by the local pathologist was 0.18%/year, the incidence when there was agreement between the local and one central pathologist was 0.21%/year, and the incidence when all 3 pathologists were in agreement was 0.39%/year) or combined HGD and EAC (0.94%/year, 0.87%/year, and 0.84%/year, respectively). CONCLUSIONS: Overall, patients with BE and LGD have a low annual incidence of EAC, similar to nondysplastic BE. There are no risk factors for progression and there is significant interobserver variation in diagnosis, even among expert pathologists.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/patologia , Esôfago/patologia , Lesões Pré-Cancerosas/patologia , Adenocarcinoma/mortalidade , Idoso , Esôfago de Barrett/mortalidade , Biópsia , Progressão da Doença , Neoplasias Esofágicas/mortalidade , Esofagoscopia , Feminino , Humanos , Incidência , Estimativa de Kaplan-Meier , Masculino , Metaplasia , Pessoa de Meia-Idade , Variações Dependentes do Observador , Lesões Pré-Cancerosas/mortalidade , Valor Preditivo dos Testes , Prevalência , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia
7.
Gastroenterology ; 141(2): 460-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21679712

RESUMO

BACKGROUND & AIMS: Radiofrequency ablation (RFA) can eradicate dysplasia and intestinal metaplasia in patients with dysplastic Barrett's esophagus (BE), and reduce rates of esophageal adenocarcinoma. We assessed long-term rates of eradication, durability of neosquamous epithelium, disease progression, and safety of RFA in patients with dysplastic BE. METHODS: We performed a randomized trial of 127 subjects with dysplastic BE; after cross-over subjects were included, 119 received RFA. Subjects were followed for a mean time of 3.05 years; the study was extended to 5 years for patients with eradication of intestinal metaplasia at 2 years. Outcomes included eradication of dysplasia or intestinal metaplasia after 2 and 3 years, durability of response, disease progression, and adverse events. RESULTS: After 2 years, 101 of 106 patients had complete eradication of all dysplasia (95%) and 99 of 106 had eradication of intestinal metaplasia (93%). After 2 years, among subjects with initial low-grade dysplasia, all dysplasia was eradicated in 51 of 52 (98%) and intestinal metaplasia was eradicated in 51 of 52 (98%); among subjects with initial high-grade dysplasia, all dysplasia was eradicated in 50 of 54 (93%) and intestinal metaplasia was eradicated in 48 of 54 (89%). After 3 years, dysplasia was eradicated in 55 of 56 of subjects (98%) and intestinal metaplasia was eradicated in 51 of 56 (91%). Kaplan-Meier analysis showed that dysplasia remained eradicated in >85% of patients and intestinal metaplasia in >75%, without maintenance RFA. Serious adverse events occurred in 4 of 119 subjects (3.4%); the rate of stricture was 7.6%. The rate of esophageal adenocarcinoma was 1 per 181 patient-years (0.55%/patient-years); there was no cancer-related morbidity or mortality. The annual rate of any neoplastic progression was 1 per 73 patient-years (1.37%/patient-years). CONCLUSIONS: In subjects with dysplastic BE, RFA therapy has an acceptable safety profile, is durable, and is associated with a low rate of disease progression, for up to 3 years.


Assuntos
Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Esôfago de Barrett/cirurgia , Ablação por Cateter/métodos , Neoplasias Esofágicas/patologia , Esôfago/patologia , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/cirurgia , Conduta Expectante , Idoso , Ablação por Cateter/efeitos adversos , Progressão da Doença , Epitélio/patologia , Esofagoscopia , Feminino , Humanos , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Metaplasia , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Gastrointest Endosc ; 75(1): 23-31.e2, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22100301

RESUMO

BACKGROUND: Guidelines suggest that patients with nondysplastic Barrett's esophagus (BE) undergo endoscopic surveillance every 3 to 5 years, but actual use of surveillance endoscopy and the determinants of variation in surveillance intervals are not known. OBJECTIVE: To measure use of surveillance endoscopy and its variation in patients with nondysplastic BE. DESIGN: Multicenter, cross-sectional study. SETTING: Three sites in Arizona, Minnesota, and North Carolina. PATIENTS: This study involved patients who had prevalent BE without a history of high-grade dysplasia or esophageal adenocarcinoma. INTERVENTION: Participants were given validated measures of quality of life, numeracy, and cancer risk perception, and the total number of prior endoscopic surveillance examinations was measured. MAIN OUTCOME MEASUREMENTS: Oversurveillance was defined as >1 surveillance examination per 3-year period. RESULTS: Among 235 patients with nondysplastic BE, 76% were male and 94% were white. The average (± standard deviation [SD]) duration of BE was 6.5 ± 5.9 years. The mean (± SD) number of endoscopies per 3-year period was 2.7 ± 2.6. Oversurveillance was present in 65% of participants, resulting in a mean of 2.3 excess endoscopies per patient. Neither numeracy skills nor patient perception of cancer risk were associated with oversurveillance. LIMITATIONS: Endoscopies were measured by patient report, which is subject to error. Results may be generalizable only to patients seen in academic centers. CONCLUSION: Most patients with nondysplastic BE had more surveillance endoscopic examinations than is recommended by published guidelines. Patient factors did not predict oversurveillance, indicating that other factors may influence decisions about the interval and frequency of surveillance examinations.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/patologia , Neoplasias Esofágicas/diagnóstico , Esofagoscopia/estatística & dados numéricos , Lesões Pré-Cancerosas/patologia , Procedimentos Desnecessários/estatística & dados numéricos , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/psicologia , Distribuição de Qui-Quadrado , Estudos Transversais , Neoplasias Esofágicas/patologia , Feminino , Fidelidade a Diretrizes , Azia , Humanos , Seguro Saúde , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Percepção , Guias de Prática Clínica como Assunto , Lesões Pré-Cancerosas/psicologia , Qualidade de Vida , Vigilância de Evento Sentinela , Índice de Gravidade de Doença , Fatores de Tempo
11.
Clin Gastroenterol Hepatol ; 9(3): 220-7; quiz e26, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21115133

RESUMO

BACKGROUND & AIMS: The risks of dysplasia and esophageal adenocarcinoma (EAC) are not clear for patients with nondysplastic Barrett's esophagus (NDBE); the rate of progression has been overestimated in previous studies. We studied the incidences of dysplasia and EAC and investigated factors associated with progression of BE. METHODS: The BE study is a multicenter outcomes project of a large cohort of patients with BE. Neoplasia was graded as low-grade dysplasia, high-grade dysplasia (HGD), or EAC. Patients followed up for at least 1 year after the index endoscopy examination were included, whereas those diagnosed with dysplasia and EAC within 1 year of diagnosis with BE (prevalent cases) were excluded. Of 3334 patients with BE, 1204 met the inclusion criteria (93.7% Caucasian; 88% male; mean age, 59.3 y) and were followed up for a mean of 5.52 years (6644.5 patient-years). RESULTS: Eighteen patients developed EAC (incidence, 0.27%/y; 95% confidence interval [CI], 0.17-0.43) and 32 developed HGD (incidence, 0.48%/y; 95% CI, 0.34-0.68). The incidence of HGD and EAC was 0.63%/y (95% CI, 0.47-0.86). There were 217 cases of low-grade dysplasia (incidence, 3.6%/y; 95% CI, 3.2-4.1). Five and 10 years after diagnosis, 98.6% (n = 540) and 97.1% (n = 155) of patients with NDBE were cancer free, respectively. The length of the BE was associated significantly with progression (EAC <6 cm, 0.09%/y vs EAC ≥ 6 cm, 0.65%/y; P = 0.001). CONCLUSIONS: There is a lower incidence of dysplasia and EAC among patients with NDBE than previously reported. Because most patients are cancer free after a long-term follow-up period, surveillance intervals might be lengthened, especially for patients with shorter segments of BE.


Assuntos
Adenocarcinoma/epidemiologia , Esôfago de Barrett/complicações , Neoplasias Esofágicas/epidemiologia , Adenocarcinoma/patologia , Idoso , Endoscopia Gastrointestinal , Neoplasias Esofágicas/patologia , Esôfago/patologia , Feminino , Seguimentos , Histocitoquímica , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Medição de Risco , Índice de Gravidade de Doença , Análise de Sobrevida
12.
Clin Gastroenterol Hepatol ; 7(7): 716-20, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19306943

RESUMO

Recent retrospective cohort data and a prospective randomized sham controlled trial have clearly documented the impact of endoscopic ablation therapy on dysplasia and Barrett's esophagus (BE). The clinical indications for ablation of BE includes high-grade dysplasia and intramucosal adenocarcinoma. The techniques of resection of mucosal irregularities and of ablation are reviewed, primarily thermal and photodynamic ablation. Ablation of BE with neoplasia has appropriately entered the clinical arena.


Assuntos
Técnicas de Ablação/métodos , Esôfago de Barrett/cirurgia , Endoscopia/métodos , Humanos
13.
Clin Gastroenterol Hepatol ; 7(12): 1299-304, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19523538

RESUMO

BACKGROUND & AIMS: Experimental evidence indicates that proton pump inhibitors (PPIs), nonsteroidal anti-inflammatory drugs (NSAIDs)/aspirin, and statins can protect patients with Barrett's esophagus (BE) from developing neoplasias. However, only limited data are available on chemoprevention in patients with BE. METHODS: A retrospective observational study was performed using data from patients with documented BE. Prescription information was collected from pharmacy records. Cox regression analyses were performed to examine the association between prescriptions for PPIs, NSAIDs/aspirin, or statins and the risk of developing esophageal dysplasia or adenocarcinoma during follow-up (from 1982 to 2005). RESULTS: We examined 344 patients diagnosed with BE (mean age 61 years, 90.4% Caucasian, 94.2% male). After BE diagnosis, 67.2% of the patients were prescribed PPIs for a mean duration of 5.1 years; 49.1% were prescribed NSAIDs for a mean duration of 3.6 years, and 25.3% were prescribed statins for a mean duration of 2.8 years. During 2620 patient-years, high grade dysplasia or esophageal adenocarcinoma developed in 33 patients. PPI treatment after BE diagnosis was associated with a reduced risk of high grade dysplasia or cancer; this association persisted after adjustment for gender, age, and the length of BE. NSAID and/or aspirin therapy were associated with a nonsignificant trend toward lower incidence of high grade dysplasia or esophageal cancer. CONCLUSIONS: PPI therapy reduces the risk of neoplasms in patients with BE. NSAIDs/aspirin appear to reduce cancer risk whereas statin use is not significantly associated with the risk of neoplasia in patients with BE.


Assuntos
Esôfago de Barrett/complicações , Esôfago de Barrett/tratamento farmacológico , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/prevenção & controle , Adesão à Medicação/estatística & dados numéricos , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/uso terapêutico , Estudos Retrospectivos , Fatores de Risco
14.
Am J Gastroenterol ; 104(2): 302-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19174784

RESUMO

OBJECTIVES: Barrett's esophagus (BE) is a metaplastic lesion characterized by replacement of the normal squamous epithelium by columnar intestinal epithelium containing goblet cells. It is speculated that this process is an adaptation to protect cells from components of refluxate, such as gastric acid and bile acids. In contrast to the normal squamous epithelium, enterocytes of the distal ileum are adapted to transport bile acids from the intestinal lumen. Several bile acid transporters are utilized for effective removal of bile acids, including the apical sodium-dependent bile acid transporter (ASBT), the ileal bile acid-binding protein (IBABP), and the multidrug-resistant protein 3 (MRP3). We hypothesized that one of the possible functions of newly arising metaplastic epithelium, in the esophagus, is to transport bile acids. Our major goal was to evaluate the expression of bile acid transporters in normal squamous epithelium, BE with different grades of dysplasia, and esophageal adenocarcinoma (EAC). METHODS: A total of 101 patients were included in this study. Immunohistochemistry (IHC) and reverse transcriptase (RT)-PCR were used to detect the expression of these transporters at the mRNA and protein levels. RESULTS: Our immunohistochemical studies showed that all three bile acid transporters are expressed in BE glands, but not in squamous epithelium. ASBT was found in the apical border in BE biopsies. The highest frequency of ASBT expression was in patients with nondysplastic BE (9 of 15, 60%), and a progressive loss of ASBT was observed through the stages of dysplasia. ASBT was not detected in EAC (0 of 15). IBABP staining was observed in the cytoplasm of BE epithelial surface cells. Expression of IBABP was found in 100% of nondysplastic BE (14 of 14), in 93% of low-grade dysplasia (LGD, 15 of 16), in 73% of high-grade dysplasia (HGD, 10 of 14), and in 33% of EAC (5 of 15). MRP3 was expressed in the basolateral membrane in 93% of nondysplastic BE (13 of 14), in 60% of LGD (10 of 16), and in 86% of HGD (11 of 13). Only weak MRP3 staining was detected in EAC biopsies (5 of 15, 33%). In addition, RT-PCR studies showed increased expression of mRNA coding for ASBT (6.1x), IBABP (9.1x), and MRP3 (2.4x) in BE (N=13) compared with normal squamous epithelium (N=15). Significantly increased mRNA levels of IBABP (10.1x) and MRP3 (2.5x) were also detected in EAC (N=21) compared with normal squamous epithelium. CONCLUSIONS: We found that bile acid transporters expression is increased in BE tissue at the mRNA and protein levels and that expression of bile acid transporter proteins decreased with progression to cancer.


Assuntos
Adenocarcinoma/metabolismo , Esôfago de Barrett/metabolismo , Proteínas de Transporte/metabolismo , Neoplasias Esofágicas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Simportadores/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Proteínas de Transporte/genética , Estudos de Casos e Controles , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/genética , Metaplasia , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Simportadores/genética
15.
Clin Cancer Res ; 13(18 Pt 1): 5305-13, 2007 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17875759

RESUMO

OBJECTIVES: The molecular factors contributing to the development of Barrett's esophagus (BE) are unclear. Our previous studies showed that BE tissues secrete interleukin-6 (IL-6) and express proteins associated with IL-6 signaling, including IL-6 receptor, activated signal transducer and activators of transcription 3 (STAT3), and antiapoptotic proteins Bcl-x(L) and Mcl-1. Here, we test the hypothesis that bile acids and gastric acids, two components of refluxate associated with gastresophageal reflux disease, activate the IL-6/STAT3 pathway. MATERIALS AND METHODS: Immunohistochemistry was used to assess levels of phosphorylated STAT3 in esophageal tissue samples from BE patients with different grades of dysplasia. Seg-1 esophageal adenocarcinoma cells were evaluated for STAT3 activation and IL-6 and Bcl-x(L) expression by molecular biology techniques, including Western blot, reverse transcription-PCR, and ELISA after exposure to control media (pH 7.4), media supplemented with a 0.1 mmol/L bile acid cocktail with media at pH 4 or media at pH 4 with bile acid cocktail. RESULTS: Immunohistochemical analysis showed that activated, phosphorylated STAT3 is expressed in nuclei of dysplastic BE and cancer tissues. Treatment of Seg-1 cells with media containing bile acid cocktail and acidified to pH 4 resulted in increased activation of STAT3, IL-6 secretion, and increased expression of Bcl-x(L). Inhibition of the STAT3 pathway using STAT3 small interfering RNA or Janus-activated kinase inhibitor resulted in increased apoptosis. CONCLUSIONS: The IL-6/STAT3 antiapoptotic pathway is induced by short exposure to bile acid cocktail and low pH. This alteration, if persistent in vivo, may underlie the development of dysplastic BE and tumor progression.


Assuntos
Esôfago de Barrett/metabolismo , Ácidos e Sais Biliares/metabolismo , Esôfago/metabolismo , Interleucina-6/metabolismo , Fator de Transcrição STAT3/metabolismo , Adenocarcinoma/química , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Esôfago de Barrett/patologia , Ácidos e Sais Biliares/farmacologia , Neoplasias Esofágicas/química , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Esôfago/efeitos dos fármacos , Esôfago/patologia , Feminino , Ácido Gástrico/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Interleucina-6/genética , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Fator de Transcrição STAT3/análise , Fator de Transcrição STAT3/genética , Células Tumorais Cultivadas , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
16.
Int J Cancer ; 121(10): 2132-9, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17594693

RESUMO

Given the poor survival rate and efficacy of current therapy for esophageal adenocarcinoma (EAC), there is a need to identify and develop new therapeutic targets for treatment. Microarray analysis (Affymetrix U133A GeneChips, Robust Multi-Chip Analysis) was used to expression profile 11 normal squamous and 18 Barrett's esophagus biopsies, 7 surgically resected EACs and 3 EAC cell lines. Two hundred transcripts representing potential therapeutic targets were identified using the following criteria: significant overexpression in EAC by analysis of variance (p = 0.05, Benjamini Hochberg false discovery rate); 3-fold increase in EAC relative to normal and Barrett's esophagus and expression in at least 2 of the 3 EAC cell lines. From the list of potential targets we selected TNFRSF12A/Fn14/TWEAK receptor, a tumor necrosis factor super-family receptor, for further validation based on its reported role in tumor cell survival and potential as a target for therapy. Fn14 protein expression was confirmed in SEG-1 and BIC-1 cell lines, but Fn14 was not found to affect tumor cell survival after exposure to chemotherapeutics as expected. Instead, a novel role in EAC was discovered in transwell assays, in which modulating Fn14 expression affected tumor cell invasion. Fn14's potential as a therapeutic target was further supported by immunohistochemistry on a tissue microarray of patient samples that showed that Fn14 protein expression increased with disease progression in EAC.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Esofágicas/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Biópsia , Linhagem Celular , Progressão da Doença , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/terapia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/patologia , RNA Mensageiro/genética , Receptores do Fator de Necrose Tumoral/genética , Receptor de TWEAK
17.
Med Clin North Am ; 89(2): 293-312, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15656928

RESUMO

The definition of BE has evolved over time. BE is the key premalignant lesion for developing EAC. The epidemiology and pathophysiology of BE is outlined, and risk factors for BE and EAC are reviewed. GERD plays a crucial role in the pathophysiology and the clinical identification of BE. Endoscopy with biopsy is the best tool for diagnosing and surveying patients with BE. Detection of early neoplasia is the present approach to reduce EAC mortality. Novel technology should assist in the early detection of dysplasia to enable targeted therapy. Effective chemopreventive strategies may reduce the risk of progression to EAC.


Assuntos
Adenocarcinoma/mortalidade , Esôfago de Barrett/epidemiologia , Neoplasias Esofágicas/mortalidade , Esôfago de Barrett/fisiopatologia , Esôfago de Barrett/terapia , Humanos
18.
Drugs ; 63(6): 555-64, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12656653

RESUMO

Barrett's oesophagus is a change in the lining of the distal oesophagus recognised at endoscopy and documented to have intestinal metaplasia by biopsy. It is thought that it is an acquired condition resulting from chronic gastro-oesophageal reflux disease (GORD). Barrett's oesophagus has the potential to progress to adenocarcinoma of the oesophagus. Evidence to support the association between Barrett's oesophagus and GORD appears to be strong but circumstantial. The intermediate steps that lead from GORD to Barrett's oesophagus are speculative and the timeline for the development of this condition remains obscure. It has yet to be demonstrated that erosive oesophagitis is a necessary intermediate step for the development of Barrett's oesophagus. In spite of effective therapy, documentation that medical or surgical therapy prevents Barrett's oesophagus is lacking. The goal of screening for Barrett's oesophagus is ultimately to improve the survival of patients with adenocarcinoma of the oesophagus. This goal has not been achieved and the evidence-based criteria for screening remain to be defined. Medical and surgical therapy of Barrett's oesophagus is effective in controlling reflux, although not proven to prevent neoplastic progression of the at risk mucosa. Endoscopic techniques of mucosal injury have been applied as alternatives to oesophagectomy in efforts to prevent progression to cancer. Surveillance endoscopy and biopsy is the currently accepted method aimed at early intervention and improved survival for oesophageal adenocarcinoma. A working surveillance protocol to accomplish this is proposed based on dysplasia grade. If no dysplasia is found and confirmed with subsequent endoscopy and biopsy, a 3-year interval is recommended. If only low grade dysplasia is confirmed, then annual endoscopy until no dysplasia is recognised is recommended. On the basis of defined risk factors, high grade dysplasia can lead to intense surveillance every 3 months or an intervention. Future developments in understanding the biology of Barrett's oesophagus and in therapeutic interventions will provide an opportunity for more effective screening, surveillance and prevention of neoplastic progression.


Assuntos
Esôfago de Barrett/prevenção & controle , Adenocarcinoma/etiologia , Adenocarcinoma/prevenção & controle , Esôfago de Barrett/tratamento farmacológico , Esôfago de Barrett/etiologia , Esôfago de Barrett/cirurgia , Progressão da Doença , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/prevenção & controle , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/prevenção & controle , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Humanos , Inibidores da Bomba de Prótons , Bombas de Próton/uso terapêutico
20.
Gastrointest Endosc Clin N Am ; 13(3): 449-55, vi, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14629101

RESUMO

Multipolar electrocoagulation (MPEC) is a readily available technique that can be applied for endoscopic ablation of Barrett's esophagus. MPEC, in combination with high dose proton pump inhibitor therapy or antireflux surgery, results in normal squamous epithelium in most patients without major adverse effects. The ultimate clinical role of MPEC has not been determined but may be adjunctive to other techniques in appropriately selected patients at high risk for neoplastic progression.


Assuntos
Esôfago de Barrett/cirurgia , Eletrocoagulação/métodos , Esôfago de Barrett/patologia , Ensaios Clínicos como Assunto , Esofagoscopia , Humanos
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