OPEN VERSUS LAPAROSCOPIC SURGERY - A COMPARISON OF NATURAL ANTITUMORAL CELLULAR-IMMUNITY IN A SMALL ANIMAL-MODEL

The scope of laparoscopic surgery has extended to the treatment of can cer. The immunological impact of laparoscopic surgery as compared with open surgery has not been well characterized. A paucity of informatio n is available about differences or similarities of these two methods regarding natural antitumoral cellular immunity, namely, natural kille r cell cytotoxicity. This study compared the activity of natural kille r cells in rats subjected to pneumoperitoneum, open dissection of the retroperitoneum, and laparoscopic dissection of the retroperitoneum. W hen compared to control animals, rats subjected to pneumoperitoneum di d not show any change in natural killer cell activity. Conversely, the groups of open surgery and laparoscopic surgery revealed significantl y decreased natural killer cell cytotoxicity compared with controls (P < 0.0167). When the laparoscopic and the open surgical groups were co mpared to each other, no difference was found. In this study, both ope n and laparoscopic surgery had a suppressive effect upon the natural a ntitumoral cellular immunity. Pneumoperitoneum did not have an immune suppressive effect on natural killer cell activity. In this model, the advantages of laparoscopic surgery do not apply to natural antitumora l cellular immunity.