Comparative Evaluation of Immune Responses after Laparoscopic and Open Surgery in Patients with Colorectal Cancer

ABSTRACT

PURPOSE: The laparoscopic approach is thought to reduce postoperative immunologic and metabolic effects after surgery compared to the open approach. This study was designed to compare the systemic immune and metabolic responses after laparoscopic and open surgery in patients with colorectal cancer. METHODS: Forty-four patients with colorectal cancer were prospectively assigned to undergo either a laparoscopic (n=22) or open (n=22) approach. The postoperative immune and metabolic responses were assessed by measuring the serum level of the relative proportion of lymphocytes, the T-cell count, the natural killer cell (NK-cell) count, the human leukocyte antigen-DR (HLA-DR) expression on monocytes, the interleukin-6 (IL-6), and the C-reactive protein (CRP) at specific time intervals. RESULTS: Both approaches resulted in a significant decrease in lymphocyte count, T-cell count, NK-cell count, and HLA-DR expression on monocytes at 2, 24, and 72 hours postoperatively. However, the decrease in HLA-DR expression on monocytes was more significant in open surgery at 2 hour postoperatively (mean level, laparoscopic 90.9% vs. open 83.1%, P<0.001). Significant rises in IL-6 and CRP were demonstrated within 72 hour postoperatively in both groups. However, no significant difference between the two groups was seen. CONCLUSIONS: Although both laparoscopic and open surgery in patients with colorectal cancer evoked an alteration of the systemic inflammatory and immune response, our data showed that a HLA-DR expression on monocytes may be less compromised after laparoscopic approach for an immediate postoperative period. However, clearer evidence from large-scaled prospective randomized trials are needed.