Dual effect of laparoscopy on cell-mediated immunity

Laparoscopic influence on cell-mediated immunity and tumour evolution is co ntroversial. The objective of the present study was to assess tumour growth and immune patterns after laparoscopy on an experimental study. Lewis rats , bearing an intrapancreatic ductal carcinoma randomly underwent one of the following 2-hour procedures: anaesthesia, laparotomy or CO2 pneumoperitone um. Cell-mediated immunity was investigated through determination of serum IL1 beta concentrations by ELISA and INF alpha, IL6 and iNOS gene transcrip tions in blood white cells and peritoneal cells by RT-PCR 1 day after opera tion. Tumour growth and spread patterns were assessed on anatomopathologica l examination 2 weeks after surgery. Tumour growth and spread were unaffect ed no matter what procedure was applied, but port-site seeding occurred in half of the cases undergoing laparoscopy. No significant change in acute-ph ase protein response, represented by IL1 beta serum concentration, was foun d after laparoscopy. TNF alpha, IL6 and inducible NO synthase gene transcri ptions were enhanced in blood white cells and depressed in peritoneal immun e cells after laparoscopy. In our experimental conditions, cell-mediated im mune response to CO2 pneumoperitoneum seems to be a good systemic immune ac tivation and a less acute peritoneal immune response as opposed to control laparoscopy. This early impairment of peritoneal macrophage immune activity , observed after a long-lasting CO2 pneumoperitoneum, might be responsible for the high rate of port site recurrence. Copyright (C) 2000 S. Karger AG, Basel.