Abstract
Background and aims Chemoradiotherapy for head and neck cancer (HNC) with/without laryngectomy commonly causes dysphagia. Pharyngoesophageal junction (PEJ) stricturing is an important contributor. We aimed to validate a functional lumen imaging probe (the EndoFLIP system) as a tool for quantitating pretreatment PEJ distensibility and treatment-related changes in HNC survivors with dysphagia and to evaluate the diagnostic accuracy of EndoFLIP-derived distensibility in detecting PEJ strictures.
Methods We studied 34 consecutive HNC survivors with long-term (> 12 months) dysphagia who underwent endoscopic dilation for suspected strictures. Twenty non-dysphagic patients undergoing routine endoscopy served as controls. PEJ distensibility was measured at endoscopy with the EndoFLIP system pre- and post-dilation. PEJ stricture was defined as the presence of a mucosal tear post-dilation.
Results PEJ stricture was confirmed in 22/34 HNC patients (65 %). During distension up to 60 mmHg, the mean EndoFLIP-derived narrowest cross-sectional area (nCSA) in HNC patients with strictures, without strictures, and in controls were 58 mm2 (95 % confidence interval [CI] 22 to 118), 195 mm2 (95 %CI 129 to 334), and 227 mm2 (95 %CI 168 to 316), respectively. A cutoff of 114 mm2 for the nCSA at the PEJ had perfect diagnostic accuracy in detecting strictures (area under the receiver operating characteristic curve = 1). In patients with strictures, a single session of dilation increased the nCSA by 29 mm2 (95 %CI 20 to 37; P < 0.001). In patients with no strictures, dilation caused no change in the nCSA (mean difference 13 mm2 [95 %CI −4 to 30]; P = 0.13).
Conclusions EndoFLIP is a highly accurate technique for the detection of PEJ strictures. EndoFLIP may complement conventional diagnostic tools in the detection of pharyngeal outflow obstruction.
S1450 Use of Endoscopic Functional Lumen Imaging Probe (EndoFLIP®) to Assess Pyloric Sphincter Function: A Pilot Study in Subjects With and Without Gastroparesis
