The landmark COST trial helped establish laparoscopic colectomy as an oncologically credible alternative to open surgery for selected patients with colon cancer. In this multicentre randomized trial, patients with resectable colon cancer were assigned to laparoscopic-assisted or open colectomy and followed for recurrence, survival and perioperative outcomes. The study found no clinically important disadvantage in cancer control with the laparoscopic approach. At the same time, laparoscopic surgery was associated with several of the recovery advantages expected from minimally invasive surgery, although the operation required greater technical expertise and operative time during the early era of adoption. For surgeons, the importance of COST extends beyond its historical result. It demonstrated that a less invasive access strategy does not necessarily compromise oncological principles when the procedure is performed appropriately. The findings supported wider adoption of laparoscopic colectomy and helped shift colorectal surgery toward standardized minimally invasive techniques. The practical message for current practice is that minimally invasive colon cancer surgery should be judged by oncological quality, patient selection, technical proficiency and perioperative pathways—not simply by incision size. This evidence base underpins the modern role of laparoscopy in colorectal surgery.