Distribution of intrasplenically injected colon cancer cells following pneumoperitoneum in mice

Background: Few studies have examined tumor cell distribution following laparoscopic surgery for colorectal cancer. We examined the effect of carbon dioxide pneumoperitoneum on the distribution of intrasplenically injected colon cancer cells in mice. Methods: Mice were intrasplenically injected with 2 × 104 colon 26 cells labeled with 111In-oxine and were randomized to undergo pneumoperitoneum at 10 mmHg for 30 min or to receive no treatment other than anesthesia. Radioactivity of the liver, lungs, and spleen was measured 30, 60, 90, or 150 min following tumor inoculation. Results: The dynamic changes in the hepatic radioactivity were not similar between groups. However, the values were not significantly different at any time point. The radioactivity of lungs was extremely low in both groups throughout the experimental period. Conclusions: Pneumoperitoneum does not appear to cause the accumulation of intraportally spreading tumor cells in the liver, but it may affect the dynamic changes of tumor cells. Also, tumor cell localization in the lungs is negligible in both pneumopentoneum and control groups.