The effect of pneumoperitoneum on dissemination and scar implantation of intra-abdominal tumor cells

Purpose: The role of laparoscopy for the treatment of cancer remains controversial, and a particular concern is port site metastases after laparoscopic surgery. Since laparoscopy is being performed with increasing frequency, the question arises as to whether it is a safe oncological procedure. After intraperitoneal inoculation of renal cell carcinoma cells in a mouse model, we compare abdominal wall scar implantation following laparoscopic trocar insertion and pneumoperitoneum with standard laparotomy, and examine the effects on tumor dissemination in the peritoneal cavity. Materials and Methods: Following intra-abdominal RENCA cell inoculation, Balb/c mice were randomized into group 1-20 mice that underwent carbon dioxide pneumoperitoneum and telescope trocar insertion, group 2-20 subjected to laparotomy and group 3-10 anesthetized only. All animals were sacrificed 2 weeks after inoculation, and abdominal wall metastases and intraperitoneal tumor distribution were evaluated. Results: Overall, intra-abdominal implantation of inoculated RENCA tumor cells was detected in 15 of 20 animals (75%) in group 1, 14 of 20 (70%) in group 2 and 10 of 10 (100%) in group 3. Wound metastases developed in 46.7% of the mice in group 1 and 50% in group 2. Conclusions: There was no difference among the groups in the pattern of intraperitoneal tumor implants and scar seeding incidence. Pneumoperitoneum does not facilitate port site metastases.