Cell-mediated immune response is better preserved by laparoscopy than laparotomy

Background. This study compares the effects of carbon dioxide pneumoperiton eum versus laparotomy on cellular-mediated immune response in a murine mode l. Methods. Sixty-eight female C3H/He mice were sensitized to keyhole limpet h emocyanin (KLH) and to a mouse mammary carcinoma cell line (MC2) before sur gery. Animals were randomized into 4 groups: group I, anesthesia (control); group II, pneumoperitoneum with carbon dioxide; group III, extraperitoneal wound; group IV laparotomy. All animals were challenged subsequently with KLH and MC2 tumor cells. Delayed-type hypersensitivity skin reaction (DTH) to KLH was measured on postoperative days (PODs) 1, 2, 4, and 5. Tumor grow th was assessed weekly as an indicator of postoperative cellular immune res ponse. Results. Compared with preoperative values, postoperative DTH skin reaction s were significantly less for all PODs in groups III and IV (P < .05), on P OD 1 and 4 in group II (P < .05) and POD 4 for group I (P < .05). Group IV showed significantly fewer DTH skin reactions for all PODs compared with gr oups I and II (P < .05) and all PODs except on day 2 compared with group II I (P < .05). Tumor growth was significantly increased at postoperative week 2 (n = 3/17 mice) and 3 (n = 4/17 mice) in group IV when compared with gro ups I and II (P < .05). Conclusions. Cellular immunity is preserved after carbon dioxide pneumoperi toneum compared with extraperitoneal incisions and laparotomy as measured b y DTH and the ability to reject an immuno-genictumor.