Based on the Phase I and II studies of DVDMS-PDT and the es-ORR (35%) for Photofrin in treating completely obstructive esophageal cancer, it is assumed that the expected es-ORR for the DVDMS-PDT group is 35%, and the expected es-ORR for the physician’s choice group is 10%. With a one-sided Type I error of 0.025 and a statistical power of 90%, 86 patients are required in the experimental group and 43 patients in the control group. Considering an approximate dropout rate of 30%, a total of approximately 186 patients will be enrolled, with 124 in the experimental group and 62 in the control group.
Intention-to-Treat (ITT) Population: All randomly assigned participants will be included in the ITT population. Safety Analysis Set (SS): All enrolled participants who have undergone safety-related assessments and evaluations after enrollment will be included in the SS.
The rates and their two-sided 95% confidence intervals (CIs) for categorical variables will be calculated using the Clopper-Pearson method, and differences between the two groups will be compared using the Cochran-Mantel-Haenszel test. Time-to-event variables and their 95% CIs will be estimated using the Kaplan-Meier method, and differences in time between the two groups will be compared using the Log-rank test. Hazard ratios (HRs) and 95% CIs will be calculated using a stratified Cox regression model. Considering the possibility of crossover, sensitivity analyses will be conducted using the rank-preserving structural failure time model (RPFSTM) and/or inverse probability of censoring weighted (IPCW) methods. The mixed-effects model for repeated measures (MMRM) will be used to compare changes from baseline in the dysphagia index between the two groups, reporting the least squares means (LSMs) and standard errors (SEs) relative to baseline for each treatment group, as well as the difference in LSMs and the two-sided 95% CI between the two groups. Statistical analyses will be performed using SAS Version 9.4 or higher, with a two-sided alpha level of 0.05.
