A re-look at the modified Ryan regression scoring system in esophageal cancer-validation of prognostic significance and comparison with other less commonly used systems.

Background: Neoadjuvant chemoradiotherapy (NACRT) using CROSS protocol is currently the treatment of choice for esophageal cancer (EC). Tumor response grade (TRG) is a mandatory reporting criterion in most guidelines. One of the most commonly used TRG systems is the modified Ryan system.