Purpose: Anastomotic leak after colorectal surgery is a major complication that is associated with sepsis, prolonged hospitalization, and increased morbidity and mortality. The aim of this study was to investigate the safety of laparoscopic surgery (LS) as reflected by the anastomotic leak rate compared to open surgery (OS) for colorectal resective procedures.
Methods: From 2000 through 2007, all data relative to 4774 patients undergoing colorectal resective procedures with anastomosis (1516 laparoscopic and 3258 open) were prospectively recorded and retrospectively reviewed from IRB approved databases. Patients were equally matched with regards to site of anastomosis, pathology, date of surgery, age, gender, and BMI. The incidence of anastomotic leak was compared between the two groups according to location of bowel anastomosis, primary diagnosis, and year of surgery.
Results: There was no significant difference in anastomotic leak rate between the two groups: 2.3% of the LS group (N=35) versus 2.1% of the OS group (N=67) (p=0.57). With regards to the site of anastomosis, there was no significant difference in anastomotic leak rate between the two groups: right colectomy (p=0.32) and left colectomy (p=0.79). There was no significant difference in leak rate between the two groups when the operation was performed for cancer (p=0.6) or diverticulitis (p=1). There was a significant difference in anastomotic leak rate when the primary diagnosis was Crohn’s disease: 5.3% of the LS group versus 1.8% of the OS group (p=0.002).
Conclusions: Laparoscopic colorectal surgery is not associated with a higher risk of anastomotic leaks. The incidence of anastomotic leaks in Crohn’s patients may be higher when the procedure is done laparoscopically and needs to be studied further.

Variables		Overall	Colorectal resection with anastomosis		Anastomotic bowel leak		P Value
			lap	open	lap	open
Total number		4774	1516	3258	35(2.3%)	67(2.1%)	P=0.57
Age (Mean±SD)		55.8±17.4	51.97 ± 16.07	55.14 ± 16.62			P=0.89
BMI (Mean±SD)		27.8±6.2	27.39 +/- 6.03	28.43 +/- 6.54			P=0.25
Diagnosis	Cancer	2162 (45.3%)	282 (18.6%)	1880 (57.7%)	2.8%	2.3%	P=0.6
	Crohn's	1412 (29.6%)	247 (16.3%)	1165 (35.8%)	5.3%	1.8%	P=0.002
	Diverticulitis	588 (12.3%)	375 (24.7%)	213 (6.5%)	1.3%	0.94%	P=1
	Others	612 (12.8%)	612 (40.4%)	0 (0%)	1.5%	0%
Years	2000-20003	2822 (59.1%)	681 (44.9%)	2141 (65.7%)	3.9%	2.9%	P=0.51
	2004-2004	1952 (40.9%)	835 (55.1%)	1117 (34.3%)	3.6%	2.0%	P=0.55
Site	Right	987 (20.7%)	343 (22.6%)	644 (19.8%)	3.8%	2.6%	P=0.32
	Left	1951 (40.9%)	743 (49.0%)	1208 (37.1%)	2.4%	2.2%	P=0.79
	other	1836 (38.5%)	430 (28.4%)	1406 (43.2%)	1.7%	1.2%	P=0.23