RESUMO
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-gamma, tumor necrosis factor-alpha, 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-gamma P = .018, tumor necrosis factor-alpha 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.