Increased tumor establishment and growth after laparotomy vs laparoscopy in a murine model
J. D. Allendorf, M. Bessler, M. L. Kayton, S. D. Oesterling, M. R. Treat, R. Nowygrod and R. L. Whelan
Department of Surgery, Columbia University, New York, NY, USA.
OBJECTIVE: To test our hypothesis that tumors would be more easily
established and grow more aggressively after laparotomy than after
laparoscopy. This hypothesis was based on studies that have demonstrated
that surgery can suppress immune function and facilitate tumor growth and
that have shown preservation of immune function after laparoscopic
procedures. DESIGN: Double-blinded, randomized, control trial. SETTING:
Research laboratory and animal care facility. ANIMALS: One hundred forty 5-
to 6-week-old C3H/He female mice. INTERVENTIONS: Three experiments with
three groups each: laparotomy, insufflation, and anesthesia controls. All
animals received an intradermal inoculation of tumor cells in the dorsal
skin. The anesthesia control cohort underwent no procedure. The laparotomy
cohort underwent a midline laparotomy from the xiphoid process to the
pubis, which was closed after 30 minutes. The insufflation cohort underwent
peritoneal insufflation with carbon dioxide for 30 minutes. MAIN OUTCOME
MEASURES: Tumor volume, tumor mass, and incidence of tumor establishment.
RESULTS: In the first experiment, the tumor volumes of the anesthesia
control and insufflation groups followed a similar pattern of plateau and
regression. The tumor volumes of the laparotomy group followed a different
pattern and were significantly larger than those of the control and
insufflation groups on postoperative days 6 and 12 (P < .05 for all
comparisons). In the second experiment, tumors in the laparotomy group were
approximately three times larger than those of the control group (P <
.01) and almost twice as large as insufflation group tumors (P < .01) by
mass. In the third experiment, there was a significantly higher incidence
of tumor establishment in the laparotomy group than in the insufflation (P
< .04) or control (P < .01) groups. The incidence was not different
between the control and insufflation groups. CONCLUSIONS: Tumors were more
easily established and grew more aggressively after laparotomy than after
insufflation. These results, coupled with those that demonstrate an immune
advantage to laparoscopy over laparotomy, suggest that the difference in
observed tumor growth may be related to immune function. While much work
remains to be done, we believe these data provide evidence of a previously
undemonstrated benefit of laparoscopic intervention.
