Argon plasma coagulation in Barrett's esophagus

TO THE EDITOR: We have read with interest the recent study by Dr. Hubert Mork et al. which appeared in the January issue of the Scandinavian Journal of Gastroenterology [1]. These investigators performed argon plasma coagulation (APC) at a power setting of 60 W in 25 patients with intestinal-type Barrett’s esophagus (BE), while under continuous treatment with protonpump inhibitors. Complete squamous regeneration was obtained in 84% of the patients; during a mean follow-up of 30 months, the recurrence rate of Barrett’s epithelium was 66%. Following these poor results, the investigators conclude that optimal conditions for this procedure should be defined before undertaking other similar studies. We agree with this statement: there are too many differences in the current literature on the efficacy of APC treatment of BE, yet the cause of these discrepancies is not clear. Apparently, the higher eradication and the lower recurrence rates can be obtained using high-power APC (90 W), but at the risk of major complications. We have recently obtained a 97% complete ablation in a group of 96 non-dysplastic BE patients, with a 6.1% annual recurrence rate during a mean 36 months’ follow-up [2]. APC was performed at a power setting of 40 W and a topographic grid form was used to define the landmarks of BE mucosa, the exact areas submitted to the endoscopic ablation and all the biopsy sites targeted during the follow-up for each patient and each APC session. When the complete ablation was obtained, a further endoscopy with multiple biopsies in the precise site of the previous APC treatment was carried out 3 months later in order to ensure complete eradication. Furthermore, in our study, the control of esophageal acid exposure by laparoscopic fundoplication reduced the recurrence rate of the ablated BE, indicating that careful selection and monitoring of patients with 24-h pH-metry should be the main requisite in conducting the APC ablation trial. In fact, it is obvious to suppose a higher recurrence rate in the presence of incomplete acid suppression. Therefore, by applying a meticulous and rigorous method in sampling biopsies, defining complete ablation and ensuring the control of esophageal acid exposure, we have obtained better results using low-power APC, with a consequent low rate of minor complications. It is possible that the high recurrence rate found in some studies is perhaps not a true recurrence, but the result of an incomplete ablation; not all previous studies on this topic give a clear-cut definition of complete ablation. As pointed out by Mork et al. [1], the differences between studies are probably due to the absence of a standardized definition of complete ablation and a rigorous functional study and biopsy protocol. Doubts have been raised recently on whether it is worthwhile to treat BE with APC, considering the uncertain results, the low risk of cancer in nondysplastic BE and the costs involved [3]. Efforts should be made to apply a rigorous, standardized protocol: this seems essential in order to obtain recurrence data that can be compared with those of similar studies.