COLOR trial is a randomized, international, multi center study comparing the outcomes of laparoscopic and conventional resection of colon carcinoma with curative intent. Clinical and operative data will be collected centrally in the coordinating centre in Rotterdam, The Netherlands. Quality of life and costs will be assessed on a national basis.

The design involves allocation of all suitable consecutive patients with colon carcinoma to either of the two procedures at a randomization ratio of 1:1. The trial will be stratified according to participating centre, resection type and gender.

Disease free survival for all TNM stages after 3 years is currently about 70%. To detect a difference of 7% in disease free survival rate after 3 years between open and laparoscopic resection of colon cancer, 1200 patients will have to be included (60 vs 67%, two-sided analysis; alfa=0.05, beta=0.20, power=80% and p=0.05). All analyses will be performed on an intention to treat basis.

Inclusion Criteria:

• Solitary colon carcinoma observed at colonoscopy or on barium enema X-ray within 28-days before operation (no biopsy required)
• Polyp containing invasive carcinoma according to colonoscopic biopsy, undertaken within 28 days before operation
• Suitable for elective surgical resection by right hemicolectomy, left hemicolectomy or sigmoid resection
• Sigmoid colon tumour cranially to conjugata diagonalis on lateral view of barium enema
• BMI < 30 kg/m2
• Informed consent according to local requirements

Exclusion Criteria:

• Carcinoma of the splenic flexure
• Carcinoma of the transverse colon
• Signs of acute intestinal obstruction
• More than one colon tumour
• Scheduled need for other synchronous colon surgery
• Synchronous surgery ofr other intra-abdominal organs
• Pre-operative indication of invasion of adjacent organs
• Pre-operative evidence of distant metastases
• Previous ipsilateral colon surgery
• Other malignancies in medical history, except adequately treated basocellular carcinoma of the skin or in situ carcinoma of the cervix uteri
• Absolute contra-indications to general anaesthesia or prolonged pneumoperitoneum, such as severe cardiovascular or respiratory disease
• Pregnancy