CEACAM5 and cancer: This study aimed to examine whether high-frequency follow-up after CRC surgery reduces 5-year overall mortality, cancer-specific mortality and recurrence in patients with CRC aged ≤ 50 years.<h4>Methods</h4>The COLOFOL trial performed between 2006 and 2010 was used to analyse patients randomised to high-frequency (computed tomography [CT] of the abdomen and thorax and a carcinoembryonic antigen [CEA] test at 6, 12, 18, 24 and 36 months) versus low-frequency (CT and CEA at 12 and 36 months) follow-up after curative CRC surgery.