Chemoradiotherapy versus short-course radiotherapy for response-adapted organ preservation in early-stage and intermediate-stage rectal cancer (STAR-TREC): 12-month results of an international, multicentre, open-label, parallel-group, randomised, phase 2/3 trial

In an organ-preservation strategy for rectal cancer, long-course chemoradiotherapy clearly outperformed short-course radiotherapy: at 12 months, survival free of total mesorectal excision was 78.5% (95% CI 72.4-85.1) versus 60.6% (53.6-68.4). The international phase 2/3 STAR-TREC trial enrolled 409 patients with early-stage and intermediate-stage rectal cancer, randomised to three arms: long-course chemoradiotherapy with organ preservation, short-course radiotherapy with organ preservation, or primary surgery. Serious adverse events were uncommon across all arms. These are 12-month results and do not yet settle long-term cancer control or overall survival.