Úna C. McMenamin

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

Objective Endoscopic surveillance of Barretts 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.

PTGS2 (Cyclooxygenase-2) Expression and Survival among Colorectal Cancer Patients: A Systematic Review

Background: Studies have examined whether tumor expression of PTGS2 (also known as COX-2), an enzyme inhibited by nonsteroidal anti-inflammatory drugs such as aspirin, is associated with prognosis in patients with colorectal cancer. However, results to date have been mixed. Methods: Using terms for PTGS2 and colorectal cancer, the Medline, Embase, and Web of Science databases were systematically searched for studies published, in any language, until December 2011. Random effects meta-analyses were used to calculate pooled HRs [95% confidence intervals (CI)] for the association between PTGS2 expression and tumor recurrence, colorectal cancer–specific survival, and overall survival. Results: In total, 29 studies, which had prognostic data on 5,648 patients, met the inclusion criteria. PTGS2-positive patients were at an increased risk of tumor recurrence (n = 9 studies; HR, 2.79; 95% CI, 1.76–4.41; P < 0.001) and had poorer colorectal cancer–specific survival (n = 7; HR, 1.36; 95% CI, 1.02–1.82; P = 0.04). However, there was funnel plot asymmetry, possibly due to publication bias, for the association with cancer-specific survival but less so for recurrence. PTGS2 expression was not associated with overall survival [(n = 16; pooled unadjusted HR, 1.30; 95% CI, 0.94–1.79; P = 0.11) and (n = 9; pooled adjusted HR, 1.02; 95% CI, 0.72–1.45; P = 0.91)]. Conclusions: PTGS2 expression was associated with an increased risk of tumor recurrence and poorer colorectal cancer–specific survival but not overall survival among patients with colorectal cancer. However, confounding by tumor characteristics such as tumor stage seems likely. Impact: There is insufficient evidence to recommend PTGS2 expression as a prognostic marker in patients with colorectal cancer. Furthermore, studies providing adjusted results are required. Cancer Epidemiol Biomarkers Prev; 22(9); 1490–7. ©2013 AACR.

Adenocarcinoma risk in gastric atrophy and intestinal metaplasia: a systematic review

BackgroundGastric cancer (GC) has a poor prognosis with wide variation in survival rates across the world. Several studies have shown premalignant lesions gastric atrophy (GA) and intestinal metaplasia (IM) influence gastric cancer risk. This systematic review examines all available evidence of the risk of GC in patients with GA or IM and explores the geographical variation between countries.MethodsEMBASE, MEDLINE, Web of Science and the Cochrane Library were searched for relevant articles published to June 2016 investigating the risk of GC in individuals with GA or IM. Analysis was performed to determine variation based on geographical location. Study quality was assessed using the Newcastle-Ottawa Scale and heterogeneity between studies was also evaluated.ResultsFifteen relevant articles were identified, in which there were eight studies of GC incidence in GA and nine in IM cohorts (two articles investigated both GA and IM). The incidence rate of GC in patients with GA ranged from 0.53 to 15.24 per 1000 person years, whereas there was more variation in GC incidence in patients with IM (0.38 to 17.08 per 1000 person years). The greatest GC incidence rates were in Asian countries, for patients with GA, and the USA for those with IM (15.24 and 17.08 per 1000 person years, respectively). The largest studies (four over 25,000 person years) had an incidence rate range of 1.0–2.5 per 1000 person years, however, in general, study quality was poor and there was marked heterogeneity.ConclusionOverall there is a wide variation in annual incidence rate of GC from premalignant lesions. With the recent introduction of surveillance guidelines for gastric atrophy and intestinal metaplasia in the Western world, future assessment of this risk should be performed. Furthermore, substantial heterogeneity supports the need for more robust studies in order to pool results and determine the overall incidence rate of gastric cancer for patients with these premalignant lesions.

Proton pump inhibitor and histamine-2 receptor antagonist use and risk of liver cancer in two population-based studies

Proton pump inhibitors (PPIs) and histamine‐2 receptor antagonists (H2RAs) are commonly used. PPIs have been shown to promote liver cancer in rats; however, only one study has examined the association in humans.

Physical activity, sedentary behaviour and risk of oesophago-gastric cancer: a prospective cohort study within UK Biobank

Background Few observational studies have assessed the role of physical activity in oesophago-gastric cancer risk. Objective This prospective cohort study aimed to assess the association between physical activity and risk of oesophageal or gastric cancer. Methods A cohort of 359,033 adults aged 40–69 years were identified from the UK Biobank, which recruited participants between 2006 and 2010. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between self-reported levels of physical activity and screen-based sedentary behaviour and risk of oesophageal and gastric cancer were calculated using Cox proportional hazards models. Results During eight years of follow-up (mean = 5.5), 294 oesophageal cancer and 217 gastric cancer cases were identified. Physical activity and screen-based sedentary behaviour levels were not associated with overall oesophago-gastric cancer risk. However, when compared with low levels, high physical activity levels were associated with a significantly reduced risk of gastric non-cardia cancer (HR 0.58, 95% CI 0.37–0.95). Moderate physical activity levels were associated with a 38% reduced risk of oesophageal adenocarcinoma (HR 0.62, 95% CI 0.43–0.89), although no dose-response association was apparent. Conclusion Moderate, rather than high, physical activity levels were associated with the strongest reductions in oesophageal adenocarcinoma risk in this large UK prospective cohort.

Angiotensin receptor blocker use and gastro-oesophageal cancer survival: a population-based cohort study

Angiotensin receptor blockers (ARBs; including candesartan, losartan, olmesartan and valsartan) are widely used to treat hypertension, heart failure and diabetic neuropathy. There is considerable pre‐clinical evidence that ARBs can reduce cancer progression, particularly for gastric cancer. Despite this, epidemiological studies have yet to assess the impact of ARB use on gastro‐oesophageal cancer survival.

Sex hormone receptor expression and survival in esophageal adenocarcinoma: a prospective cohort study

Introduction A striking epidemiological feature of esophageal adenocarcinoma (EAC) is its strong, unexplained male predominance but few studies have evaluated the prevalence of sex hormone receptor expression in EAC. Results A low proportion of EAC tumors stained positive for ERα (4%) and AR (3%) while approximately one third stained positive for ERβ (31%). After a mean follow-up of 3 years (max 9 years), no significant associations were seen for ERα, ERβ or AR expression and EAC recurrence or survival. A non-significant reduction in mortality was observed for positive ERβ tumor expression, when restricting to patients with gastro-esophageal junctional (GEJ) cancer (HR 0.58, 95% CI 0.33, 1.03, p = 0.06). Materials and Methods We identified all EAC patients who underwent neo-adjuvant chemotherapy prior to surgical resection between 2004–2012 in the Northern Ireland Cancer Centre. Immunohistochemical expression of ERα, ERβ and AR was scored on triplicate cores to generate H-scores. Cox proportional hazards regression was used to evaluate the association between sex hormone receptor expression and overall, cancer-specific and recurrence-free survival. Conclusion We found little evidence of ERα or AR expression in EAC. A moderate proportion expressed ERβ and there was suggestive evidence that its expression was associated with improved survival in GEJ cancer patients.

Vitamin D receptor as a marker of prognosis in oesophageal adenocarcinoma: a prospective cohort study

Aims Vitamin D receptor (VDR) expression has been associated with survival in several cancer sites. This study aims to evaluate the association between VDR expression and prognosis in oesophageal adenocarcinoma patients. Results During a median of 2.5 (maximum 9) years of follow-up, 75 patients died. In analysis adjusted for confounders, higher VDR expression was associated with an improved overall survival (HR 0.49 95% CI 0.25–0.96) and disease-specific survival (HR 0.50 95% CI 0.26–0.99), when comparing the highest with the lowest tertile of expression. These associations were strongest in sensitivity analysis restricted to junctional tumours. Conclusions This study is the first to demonstrate that patients with higher VDR expression in oesophageal adenocarcinoma have a more favourable prognosis. Further work is needed to validate these findings, and to define the role of VDR in the aetiology, progression and management of oesophageal adenocarcinoma. Methods Oesophageal adenocarcinoma specimens and clinical data were collected from 130 patients treated with neo-adjuvant chemotherapy prior to surgical resection at the Northern Ireland Cancer Centre between 2004 and 2012. Tissue microarrays were created and immunohistochemical staining for VDR was performed on triplicate tumour cores from each resection specimen. Cox proportional hazards models were applied to evaluate associations between VDR, according to tertiles of expression, and survival outcomes.

Hormonal and reproductive factors and risk of upper gastrointestinal cancers in men: A prospective cohort study within the UK Biobank: Hormonal and reproductive factors and upper gastrointestinal cancers in men

Incidence of upper gastrointestinal cancers of the oesophagus and stomach show a strong unexplained male predominance. Hormonal and reproductive factors have been associated with upper gastrointestinal cancers in women but there is little available data on men. To investigate this, we included 219,425 men enrolled in the UK Biobank in 2006–2010. Baseline assessments provided information on hormonal and reproductive factors (specifically hair baldness, number of children fathered, relative age at first facial hair and relative age voice broke) and incident oesophageal or gastric cancers were identified through linkage to U.K. cancer registries. Unadjusted and adjusted hazard ratios (HR) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models. During 8 years of follow‐up, 309 oesophageal 210 gastric cancers occurred. There was some evidence that male pattern baldness, was associated with gastric cancer risk (adjusted HR 1.35, 95% CI 0.97, 1.88), particularly for frontal male pattern baldness (adjusted HR 1.52, 95% CI 1.02, 2.28). There was little evidence of association between other hormonal and reproductive factors and risk of oesophageal or gastric cancer, overall or by histological subtype. In the first study of a range of male hormonal and reproductive factors and gastric cancer, there was a suggestion that male pattern baldness, often used as a proxy of sex hormone levels, may be associated with gastric cancer. Future prospective studies that directly test circulating sex steroid hormone levels in relation to upper gastrointestinal cancer risk are warranted.

Medications that relax the lower oesophageal sphincter and risk of oesophageal cancer: an analysis of two independent population-based databases

Excessive lower oesophageal sphincter relaxation increases gastro‐oesophageal acid reflux, an oesophageal adenocarcinoma risk factor. Medications that relax this sphincter (benzodiazepines, calcium channel blockers, nitrates, β2 agonists and xanthines) could promote cancer. These medications were investigated in two independent datasets. In the Scottish Primary Care Clinical Informatics Unit (PCCIU) database, a nested case–control study of oesophageal cancer was performed using GP prescription records. Conditional logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CIs) for medication use and oesophageal cancer. In UK Biobank, a cohort study was conducted using self‐reported medication use. Cox regression was used to calculate hazard ratios (HRs) and 95% CIs for medication use and oesophageal cancer, and by tumour subtype. Overall, 1,979 oesophageal cancer patients were matched to 9,543 controls in PCCIU, and 355 of 475,768 participants developed oesophageal cancer in UK Biobank. None of the medications investigated were significantly associated with oesophageal cancer risk apart from β2 agonists, which were associated with increased oesophageal cancer risk in PCCIU (adjusted OR 1.38, 95% CI 1.12, 1.70) but not in UK Biobank (adjusted HR 1.21, 95% CI 0.70, 2.08). Medications that relax the lower oesophageal sphincter were not associated with oesophageal cancer, apart from β2 agonists. This increased cancer risk in β2 agonist users merits further investigation.