Downside-Up Retrograde Dilation for “Lost Cap” Retrieval as a Signature Complication of Esophageal BougieCap Dilation

A novel device designated BougieCap (Ovesco, Tübingen, Germany) has been marketed for endoscopic treatment of esophageal strictures under both visual and haptic control [1]. A recently published prospective multicenter study on the utility and complications in its mainstay indication has reported high rates of endoscopic and clinical success. On the downside, loss of the BougieCap with subsequent passage into the stool has been documented in 2/50 individuals, such that “the lost cap” may be considered a signature complication due to insufficient attachment by circular taping and/or, albeit unproven, stricture length and tightness [2]. While no clinical consequences from the lost caps were reported, potential clinical and/or medicolegal implications may arise reminiscent of small-bowel capsule retention [3]. Against this background, I would like to present the first report of successful lost BougieCap retrieval through a tight radiation-induced upper esophageal stricture. We performed BougieCap dilation in a 78-year-old male patient with high-grade dysphagia due to a complex upper esophageal stricture precluding standard scope passage after definitive radiochemotherapy for squamous cell carcinoma. In a first session, dilation with a 7and 10mm BougieCap was performed with guidewire assistance. In another session 4 days apart, 12-, 14-, and 16mm caps were used without using a guidewire. Highquality mucosal characterization within the stricture through the BougieCap in tight mucosal contact clearly revealed radiation-induced neovascularization without evidence of mucosal relapse (Fig. 1a). However, given the steeper slope at the back of the dome-shaped cap,