OBJECTIVETo investigate the effects of neoadjuvant chemotherapy on the response of surgical stress during perioperative period.

METHODSFrom July 2005 to June 2006, 30 SD rats with the same age were distributed into 3 experimental groups and 1 control group randomly. Each experimental group included 8 rats, and the control group included 6 rats. The rats in experimental groups received intravenous infusion of cyclophosphamide, while the rats in control group received IV infusion of normal sodium. The blood of rats from experimental groups was taken 30 min before and during the stimulation of abdominal surgery which was given at the end of the first, the second and the third week after receiving IV infusion cyclophosphamide. Then the plasma concentration of noradrenaline was measured respectively.

RESULTSThe IV infusion of cyclophosphamide before operation could greatly improve the plasma level of norepinephrine, and it reached peak at the end of the second week. When surgeries were given at that time, the stress response became much more seriously. The response induced by neoadjuvant chemotherapy disappeared 3 weeks later.

CONCLUSIONSNeoadjuvant chemotherapy with cyclophosphamide can induce significant stress response which is characterized by the increase of plasma level of norepinephrine. It indicates that the best time of surgery for patients who have received neoadjuvant chemotherapy with cyclophosphamide is 2 weeks later.