Foreword
Foreword
Barrett’s Oesophagus is a condition in which the normal squamous mucosa in the distal oesophagus is transformed to a metaplastic columnar mucosa. Barrett’s Oesophagus is important clinically because it is the only known precursor to oesophageal adenocarcinoma (‘OAC’), a cancer which has had the fastest rising incidence in Australia and other industrialised nations during the past three decades. Survival from advanced OAC is very poor, hence the focus on diagnosing and treating people with precancerous and early cancerous lesions. Because patients with Barrett’s Oesophagus have up to 50-fold higher risks of OAC than people without the condition, they are typically placed on surveillance programs requiring regular endoscopies. Despite their greatly increased relative risk of cancer, 95% of people with Barrett’s Oesophagus never develop OAC and 95% of patients diagnosed with OAC have no preceding diagnosis of Barrett’s Oesophagus. Thus, there is clinical uncertainty about the best way to manage this condition, both at the individual level and across the population.
These Guidelines therefore seek to assist Australian doctors and patients by providing up-to-date, evidence-based information about Barrett’s Oesophagus and early oesophageal adenocarcinoma. The development process was extensive, involving a large working group who systematically reviewed the literature to address pertinent clinical questions. Through consensus, a set of recommendations was developed which have been rated according to the underlying quality and applicability of the evidence. The Guidelines are aimed at gastroenterologists, pathologists and physicians, as well as members of teams in multi-disciplinary clinics to which patients with Barrett’s Oesophagus and OAC are referred (including surgeons, radiologists, nurse practitioners etc). As an open resource, we anticipate that the Guidelines will also be relevant and informative to primary care practitioners and their patients who may be diagnosed with this condition.
Information covered by the Guidelines includes:
1. Prevalence, incidence, natural history and risk factors for Barrett’s Oesophagus
2. Endoscopic and histologic definitions of Barrett’s Oesophagus and early oesophageal adenocarcinoma
3. Management of Barrett’s Oesophagus and early oesophageal adenocarcinoma, including modification of lifestyle factors, screening, surveillance, as well as medical, endoscopic and surgical interventions.
Importantly, these Guidelines do not extend to the management of invasive adenocarcinoma of the oesophagus.
Terminology used in the Guidelines
A recurring theme throughout the Guidelines development process has been the importance of using consistent and precise terminology to ensure that recommendations accord with the published evidence. For example, there are several histological classification schemes used internationally for describing neoplastic changes in Barrett’s Oesophagus, including the WHO scheme (‘intraepithelial neoplasia’) and the Vienna Classification (‘dysplasia’). For these Guidelines, we have followed the Vienna Classification. Another example is the use of terms such as ‘screening’ and ‘surveillance’ applied to different types of early detection activities. In line with accepted epidemiologic practice, we have reserved ‘screening’ to describe the process of identifying new cases of disease in an unselected population, whereas ‘surveillance’ describes the systematic follow-up of patients with known disease at periodic intervals as part of an early detection strategy to prevent progression to cancer.
Recently, there have been numerous developments in the field of Barrett’s Oesophagus, including new (lower) estimates of the rate of progression to cancer, new information about factors associated with progression to cancer, new ablation and resection modalities for treating dysplastic lesions, and new cost-effectiveness studies that seek to understand the impact of policy changes at a societal level. All of these have a bearing on clinical practice. That said, much uncertainty remains about key aspects of clinical management for this condition, as high-quality evidence is lacking. For this reason, we have often had to use lower quality evidence when making recommendations; this has been highlighted wherever it has occurred. Further, we have carefully reviewed comparable guidelines from international agencies to calibrate the recommendations in the light of those made elsewhere. The aim of these Guidelines is to ensure the optimal management of patients with Barrett’s Oesophagus so as to prevent (or minimise) the development of cancers among this group, balanced against the potential harms of over-investigating or over-treating those at very low risk of disease progression. While the recommendations contained herein are not prescriptive and should not override good clinical judgement, they do represent consensus views of expert practitioners and accord with international practices. Finally, the field is moving very quickly, with a number of large-scale chemoprevention trials and management trials expected to report findings in the foreseeable future, and so we envisage regular updates to the Guidelines. The Wiki environment provides an excellent platform for doing so.
Congratulations to the large team who worked so hard to bring this long-term project to fruition. Their efforts will, it is hoped, improve the management of Australians with Barrett’s Oesophagus.
Professor David Whiteman
Chair, Barrett's Oesophagus Guidelines Working Party
Head, Cancer Control Group
QIMR Berghofer Medical Research Institute