3%, a proportion that is probably more meaningful, given the limitations and the poor clinical relevance of the “intestinal metaplasia only” definition discussed above.4,12,13 The Kalixanda study report only gives data on the extent of metaplasia for the 1.6% of intestinal metaplasia positive subjects; only 5 of these 11 (31%) had

metaplasia at least 2 cm in length,55 with only 26% of subjects having metaplasia extending 3 cm or greater. The other large population endoscopic survey, part of the SILC study, was done very recently in Shanghai, China.56 Endoscopically suspected BE was present in 1.9% of subjects. Though the Prague Criteria were applied in this study, no data are given on extent in the published report.56 These data are however available to this author and are given in Table 1: the distribution of extent was similar to the Kalixanda study,55 with only 26% of subjects having a maximum extent of metaplasia 3 cm or greater. Alvelestat purchase The SILC Venetoclax datasheet study and the re-interpretation of the Kalixanda study are consistent with the generally held view, derived predominantly from clinical experience, that BE is much more prevalent in relatively prosperous countries with

predominantly Caucasian populations, compared to non-Caucasian populations which are usually substantially less prosperous. The reported very low prevalence of EA in non-Caucasian populations is consistent with their reported prevalence of BE, with the notable exception of Japan. There is lively interest in how important genetics are in determining this stark difference compared to environmental factors.53 My money is on environment being dominant! Health-check” endoscopy is offered to the general population in several Asian countries, notably Japan, China, Korea and Taiwan. Increased interest in BE in these countries selleck inhibitor has resulted in five evaluations of the prevalence of variably defined BE in health-check endoscopy subjects.57–61 Details of these studies given in Table 2 show that they have evaluated unprecedentedly huge numbers of subjects, but that they also have some significant technical limitations. The Chinese, Korean and Taiwanese studies

found, as expected, a low prevalence of endoscopically suspected BE. More than three quarters of cases had an extent less than 1 cm in the two studies that reported on such an extent (Table 2).57,61 Given that the validation studies on the Prague Criteria showed such poor reproducibility of recognition of metaplastic segments less than 1 cm,32,33 the authority of the great majority of the diagnoses of BE made in these studies appears uncertain, especially as, in the largest series, it is presumed that large numbers of endoscopists were involved. Only one report (Table 2) makes mention of provision of training on recognition of BE to participating endoscopists, but no details are given on this training, nor the criteria applied for diagnosis of BE.