Phase III trial of short-course radiotherapy followed by CAPOXIRI versus CAPOX in locally advanced rectal cancer: the ENSEMBLE trial

The two key concerns in treating locally advanced rectal cancer (LARC) are as follows: (i) prolonging survival by reducing distant metastases and (ii) maintaining anorectal function and quality of life in surviving patients by safely avoiding rectal resection. To resolve these issues, in recent years, total neoadjuvant therapy (TNT), a preoperative combination of chemoradiotherapy or short-course radiotherapy (SCRT) and systemic chemotherapy, has been developed as a multidisciplinary treatment of LARC. There have been no prospective studies on consolidation triplet versus doublet regimens after SCRT. This randomized phase III trial (the ENSEMBLE trial) aims to test the superiority of consolidation irinotecan, capecitabine, and oxaliplatin over capecitabine and oxaliplatin after SCRT as TNT for LARC. The primary endpoint will be organ preservation-adapted disease-free survival in the intention-to-treat population. Moreover, no predictive biomarkers have been established for LARC. Therefore, to explore the predictive biomarkers for estimating the response to TNT and non-operative management, we planned translational research using multi-omics data, including genomic profiling with whole-genome/transcriptome sequencing of tissue and blood samples, liquid biopsy, radiomics, digital pathology, clinical features by deep learning with artificial intelligence.