Outcome measures in multimodal rectal cancer trials
Emmanouil Fokas, Rob Glynne‐Jones, Ane Appelt, Geerard L. Beets, Geerard L. Beets, Karin Haustermans, Corrie A.M. Marijnen, Bruce D. Minsky, Ethan B. Ludmir, Philip Quirke, David Sebag‐Montefiore, Julio García‐Aguilar, Maria Antonietta Gambacorta, Vincenzo Valentini, Marc Buyse, Claus Rödel
Abstract
There is a large variability regarding the definition and choice of primary endpoints in phase 2 and phase 3 multimodal rectal cancer trials, resulting in inconsistency and difficulty of data interpretation. Also, surrogate properties of early and intermediate endpoints have not been systematically assessed. We provide a comprehensive review of clinical and surrogate endpoints used in trials for non-metastatic rectal cancer. The applicability, advantages, and disadvantages of these endpoints are summarised, with recommendations on clinical endpoints for the different phase trials, including limited surgery or non-operative management for organ preservation. We discuss how early and intermediate endpoints, including patient-reported outcomes and involvement of patients in decision making, can be used to guide trial design and facilitate consistency in reporting trial results in rectal cancer.