Risk factors for metachronous esophageal squamous cell carcinoma after endoscopic or surgical resection of esophageal carcinoma: a systematic review and meta-analysis

David Moher and colleagues introduce PRISMA, an update of the QUOROM guidelines for reporting systematic reviews and meta-analyses

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews.

Esophageal cancer is one of the most unknown and deadliest cancers worldwide, mainly because of its extremely aggressive nature and poor survival rate. Esophageal cancer is the 6(th) leading cause of death from cancer and the 8(th) most common cancer in the world. The 5-year survival is around 15%-25%. There are clear differences between the risk factors of both histological types that affect their incidence and distribution worldwide. There are areas of high incidence of squamous cell carcinoma (some areas in China) that meet the requirements for cost-effectiveness of endoscopy for early diagnosis in the general population of those areas. In Europe and United States the predominant histologic subtype is adenocarcinoma. The role of early diagnosis of adenocarcinoma in Barrett's esophagus remains controversial. The differences in the therapeutic management of early esophageal carcinoma (high-grade dysplasia, T1a, T1b, N0) between different parts of the world may be explained by the number of cancers diagnosed at an early stage. In areas where the incidence is high (China and Japan among others) early diagnoses is more frequent and has led to the development of endoscopic techniques for definitive treatment that achieve very effective results with a minimum number of complications and preserving the functionality of the esophagus.