Reply to Westerveld et al. and Schembri et al.

We thank the contributors for their insightful comments. It is reassuring that both contributors have agreed with our findings that endoscopy performed by those trained in Barrett’s surveillance results in better dysplasia detection rates (DDRs). As Westerveld et al. mention, the study design limits the further quantification of the contribution made by components of a specialist Barrett’s endoscopy list. Assessment of the variables involved in the increased DDR was not the intention of this paper and will hopefully be the subject of future research.

All patients in the specialist group underwent high definition endoscopy, and narrow-band imaging was used at the discretion of the endoscopist. The increased allocated time for surveillance and examination during withdrawal is also likely to contribute, given that the latter is known to increase the DDR [1], although the study was not designed to assess the impact of this individual aspect in isolation. The increased allocation time also allows for cleaning of the Barrett’s segment, which permits a more rigorous examination and allows better targeting of dysplasia.

Westerveld et al. also mention that the knowledge of taking part in the study may have increased the DDR. An alternative study design may have been to retrospectively assess the DDR of those with and without a certain volume of Barrett’s surveillance experience. As Schembri et al. indicate, and as intimated by Westerveld et al., the quality of surveillance as measured by adherence to the Prague classification, or the more important end point of DDR, is indeed a function of the endoscopist’s experience in Barrett’s surveillance, so that the impact of an unblinded endoscopist is likely to have a small impact. Furthermore, the volume of Barrett’s surveillance experience required to reach a satisfactory DDR has not yet been established.

Overall, the increased DDR on specialist lists is likely to be multifactorial. The increased time allocation allows better preparation and examination of the Barrett’s segment. Although not done in all cases in Group A, the grouping of patients onto dedicated lists is also likely to contribute to better DDRs. We would hope that this study helps to underline the need for expertise in Barrett’s surveillance and highlight the need for the practical organization of specialist endoscopy lists to increase DDRs.

• References

• 1 Gupta N, Gaddam S, Wani SB. et al. Longer inspection time is associated with increased detection of high-grade dysplasia and esophageal adenocarcinoma in Barrett’s esophagus. Gastrointest Endosc 2012; 76: 531-538