The humoral response after laparoscopic versus open colorectal surgery: a meta-analysis

The local and systemic humoral response after colorectal surgery is thought to affect postoperative recovery. It is commonly claimed that laparoscopic surgery elicits a diminished inflammatory response than equivalent open surgery. Despite these claims, the evidence is conflicting. Therefore, we aimed to systematically review the results from randomized controlled clinical trials comparing the humoral response associated with laparoscopic versus open colorectal surgery.

A high-sensitivity search was conducted independently by two of the authors with no language restriction. Studies were identified from the Cochrane Central Register of Controlled Trials (CENTRAL/CCTR), Cochrane Library, Medline (January 1966 to January 2009), PubMed (1950 to January 2009), and Embase (1947 to January 2009). Relevant meeting abstracts and reference lists were manually searched. Data analysis was performed using Review Manager ver. 5.0.

Thirteen randomized controlled trials were included. Meta-analysis demonstrated a significantly higher serum IL-6 on d 1 after open colorectal resection for neoplasia (n = 97) compared with laparoscopic resection (n = 76, P = 0.0008) without significant heterogeneity. Data for plasma IL-6 were heterogeneous, with no apparent difference between groups. No other significant differences were identified, and there were not enough data on local peritoneal humoral factors to allow meta-analysis.

Open colorectal resection for neoplasia is associated with higher postoperative serum levels of IL-6 on d 1 than equivalent laparoscopic surgery. The aetiology and clinical significance of this finding is uncertain, and further studies are required to elucidate any differences in the local humoral response which may be more clinically relevant in surgery for this indication.