Impact of surgery on immunologic function: comparison between minimally invasive techniques and conventional laparotomy for surgical resection of colorectal tumors

Background

Surgical trauma suppresses host immune function, potentially creating an environment vulnerable to tumor cell growth. This study compared immune function after laparoscopy, minilaparotomy, and conventional colorectal tumor resections.

Methods

Seventy-one patients underwent surgery (20 laparoscopy, 21 minilaparotomy, and 30 conventional). Blood samples were taken before surgery and at 3 hours, 24 hours, and 5 days after surgery. White blood cell constitution was determined using monoclonal antibodies. Levels of TH1 cytokines interferon-γ, tumor necrosis factor-α, and interleukin (IL)-2 and TH2 cytokines IL-10, -4, and -6 were measured in plasma and from supernatants of activated peripheral blood mononuclear cells.

Results

At 5 days after surgery, lymphocyte counts remained low in the conventional and minilaparotomy groups (P = .001 and P = .008) but had resolved in laparoscopic patients. Three-hour postoperative serum IL-6 concentrations were lower in laparoscopic than in conventional patients (P = .028). Production of TH1 cytokines 3 hours after surgery were significantly increased in laparoscopic patients (interferon-γ P = .018, tumor necrosis factor-α P = .011, and IL-2 P = .037).

Conclusions

TH1 lymphocyte function is improved transiently and immune homeostasis restored earlier in patients undergoing laparoscopic colorectal cancer resection, which may influence disease recurrence.