Oesophageal adenocarcinoma and prior diagnosis of Barrett's oesophagus: a population-based study.

OBJECTIVE: Endoscopic surveillance of Barrett's oesophagus (BO) provides an opportunity to detect early stage oesophageal adenocarcinoma (OAC). We sought to determine the proportion of OAC patients with a prior diagnosis of BO on a population basis and to evaluate the influence of a prior diagnosis of BO on survival, taking into account lead and length time biases. DESIGN: A retrospective population-based study of all OAC patients in Northern Ireland between 2003 and 2008. A prior BO diagnosis was determined by linkage to the Northern Ireland BO register. Stage distribution at diagnosis and histological grade were compared between patients with and without a prior BO diagnosis. Overall survival, using Cox models, was compared between patients with and without a prior BO diagnosis. The effect of adjusting the survival differences for histological grade and estimates of lead and length time bias was assessed. RESULTS: There were 716 OAC cases, 52 (7.3%) of whom had a prior BO diagnosis. Patients with a prior BO diagnosis had significantly lower tumour stage (44.2% vs. 11.1% had stage 1 or 2 disease; p<0.001), a higher rate of surgical resection (50.0% vs. 25.5%; p<0.001) and had a higher proportion of low/intermediate grade tumours (46.2% vs. 26.5%; p=0.011). A prior BO diagnosis was associated with significantly better survival (HR for death 0.39; 95% CI 0.27 to 0.58), which was minimally influenced by adjustment for age, sex and tumour grade (adjusted HR 0.44; 95% CI 0.30 to 0.64). Correction for lead time bias attenuated but did not abolish the survival benefit (HR 0.65; 95% CI 0.45 to 0.95) and further adjustment for length time bias had little effect. CONCLUSIONS: The proportion of OAC patients with a prior diagnosis of BO is low; however, prior identification of BO is associated with an improvement in survival in OAC patients.

Symptoms and endoscopic features at barrett's esophagus diagnosis: implications for neoplastic progression risk.

OBJECTIVES: Risk stratification of Barrett's esophagus (BE) patients based on clinical and endoscopic features may help to optimize surveillance practice for esophageal adenocarcinoma (EAC) development. The aim of this study was to investigate patient symptoms and endoscopic features at index endoscopy and risk of neoplastic progression in a large population-based cohort of BE patients. METHODS: A retrospective review of hospital records relating to incident BE diagnosis was conducted in a subset of patients with specialized intestinal metaplasia from the Northern Ireland BE register. Patients were matched to the Northern Ireland Cancer Registry to identify progressors to EAC or esophageal high-grade dysplasia (HGD). Cox proportional hazards models were applied to evaluate the association between endoscopic features, symptoms, and neoplastic progression risk. RESULTS: During 27,997 person-years of follow-up, 128 of 3,148 BE patients progressed to develop HGD/EAC. Ulceration within the Barrett's segment, but not elsewhere in the esophagus, was associated with an increased risk of progression (hazard ratio (HR) 1.72; 95% confidence interval (CI): 1.08-2.76). Long-segment BE carried a significant sevenfold increased risk of progression compared with short-segment BE; none of the latter group developed EAC during the study period. Conversely, the absence of reflux symptoms was associated with an increased risk of cancer progression (HR 1.61; 95% CI: 1.05-2.46). CONCLUSIONS: BE patients presenting with a long-segment BE or Barrett's ulcer have an increased risk of progressing to HGD/EAC and should be considered for more intense surveillance. The absence of reflux symptoms at BE diagnosis is not associated with a reduced risk of malignant progression, and may carry an increased risk of progression.

Colorectal Cancer Risk Following Adenoma Removal: A Large Prospective Population-Based Cohort Study.

BACKGROUND: Randomized controlled trials have demonstrated significant reductions in colorectal cancer incidence and mortality associated with polypectomy. However, little is known about whether polypectomy is effective at reducing colorectal cancer risk in routine clinical practice. The aim of this investigation was to quantify colorectal cancer risk following polypectomy in a large prospective population-based cohort study. METHODS: Patients with incident colorectal polyps between 2000 and 2005 in Northern Ireland were identified via electronic pathology reports received to the Northern Ireland Cancer Registry. Patients were matched to the Northern Ireland Cancer Registry to detect colorectal cancer and deaths up to December 31, 2010. Colorectal cancer standardized incidence ratios (SIR) were calculated and Cox proportional hazards modeling applied to determine colorectal cancer risk. RESULTS: During 44,724 person-years of follow-up, 193 colorectal cancer cases were diagnosed among 6,972 adenoma patients, representing an annual progression rate of 0.43%. Colorectal cancer risk was significantly elevated in patients who had an adenoma removed (SIR, 2.85; 95% CI, 2.61-3.25) compared with the general population. Male sex, older age, rectal site, and villous architecture were associated with an increased colorectal cancer risk in adenoma patients. Further analysis suggested that not having a full colonoscopy performed at, or following, incident polypectomy contributed to the excess colorectal cancer risk. CONCLUSIONS: Colorectal cancer risk was elevated in individuals following polypectomy for adenoma, outside of screening programs. IMPACT: This finding emphasizes the need for full colonoscopy and adenoma clearance, and appropriate surveillance, after endoscopic diagnosis of adenoma.

Dietary fiber and the risk of precancerous lesions and cancer of the esophagus: a systematic review and meta-analysis.

Dietary fiber has several anticarcinogenic effects and is thought to be protective against esophageal cancer. The aim of this systematic review was to quantify the association between dietary fiber and the risk of esophageal cancer by investigating histological subtypes of esophageal cancer and the stage at which fiber may influence the carcinogenic pathway. Systematic search strategies were used to identify relevant studies, and adjusted odds ratios (ORs) were combined using random-effects meta-analyses to assess the risk of cancer when comparing extreme categories of fiber intake. Ten relevant case-control studies were identified within the timeframe searched. Pooled estimates from eight studies of esophageal adenocarcinoma revealed a significant inverse association with the highest fiber intakes (OR 0.66; 95% confidence interval [CI] 0.44-0.98). Two studies also identified protective effects of dietary fiber against Barrett's esophagus. Similar, though nonsignificant, associations were observed when results from five studies of fiber intake and risk of squamous cell carcinoma were combined (OR 0.61; 95%CI 0.31-1.20). Dietary fiber is associated with protective effects against esophageal carcinogenesis, most notably esophageal adenocarcinoma. Potential methods of action include modification of gastroesophageal reflux and/or weight control.