Predictors of stricture formation after photodynamic therapy for high-grade dysplasia in Barrett's esophagus

Background: Stricture formation is the leading cause of long-term morbidity after photodynamic therapy (PDT). Risk factors for stricture formation have not been studied. Objective: To assess risk factors for stricture formation in patients undergoing PDT for Barrett's esophagus with high-grade dysplasia (HGD). Design: Retrospective cohort study. Setting: Barrett's Unit, Mayo Clinic, Rochester, Minnesota. Methods: Records of patients undergoing PDT for HGD were reviewed. Patients underwent PDT by using either bare cylindrical diffusing fibers (2.5-5.0 cm in length) or balloon diffusers with 5- to 7-cm windows. Univariate and multivariate logistic regression analyses were performed to assess risk factors for stricture formation. Main Outcome Measurement: Esophageal stricture formation. Results: Thirty-five of 131 patients (27%) developed strictures. On multivariate analysis, statistically significant predictors of stricture formation were the following: EMR before PDT was odds ratio (OR) 2.7, 95% confidence interval (CI) 1.13-6-59-1 a prior history of esophageal stricture was OR 2.7, 95% CI 1.15-6.47; and the number of PDT applications was OR 2.2, 95% CI 1.22-4.12. The OR for stricture formation in patients when centering balloons were used was 0.41, 95% CI 0.11-1.46, P = .168, indicating that centering balloons did not significantly decrease the risk of stricture formation. Limitations: Retrospective single-center study; small proportion of patients treated with centering balloons. Conclusions: Risk factors for development of strictures after PDT included history of a prior esophageal stric- i ture, performance of EMR before PDT, and more than 1 PDT application in I treatment session. The use of centering balloons was not associated with a statistically significant reduction in the risk of stricture formation.