Fifteen trials (4,207 patients) were included in the review. The mean Jadad score of the included trials was reported as 3 out of 5 points. Follow-up ranged from one to 59 months.
Complications: Based on 11 studies (2,603 patients), the risk of overall complications was lower in the laparoscopic surgery than the open surgery group (OR 0.71, 95% CI 0.58 to 0.87). Despite significant heterogeneity (p=0.004), a fixed-effect model was used.
Cancer recurrence: There was no statistically significant difference in overall recurrence, local recurrence, distant metastasis or wound site recurrence between patients in the laparoscopic and open surgery groups.
Mortality: None of the results of colorectal cancer-related mortality, colon cancer-related mortality, rectal cancer-related mortality or overall mortality reached statistical significance (p=0.07 to 0.2), but all showed lower mortality in the laparoscopic surgery group.
Removing one trial at a time in the sensitivity analysis did not significantly affect the results for complications, recurrence or mortality.
No publication bias was detected for the one outcome (recurrences) for which a funnel plot was presented.