O3-1-5 - Efficacy of Normothermic and Hyperthermic Intraperitoneal Perfusion in the Treatment of Ovarian Cancer in a Rat Model

Abstract

Background: Combination of cytoreductive surgery with following intraperitoneal chemoperfusion is considered as one of the most effective treatment strategies in patients with advanced ovarian cancer. However hyperthermic intraperitoneal perfusion (HIPEP) without chemotherapy is known for its antitumor activity while normothermic intraperitoneal perfusion (IPEP) hasn't shown to provide antitumor action. The purpose of the study is to evaluate antitumor efficacy of IPEP and HIPEP in ovarian cancer model in rats.Methods: The study was carried out in 56 Wistar female rats with ovarian cancer inoculated intraperitoneally (i.p.). Transplanted epithelian ovarian cancer strain used was originated from the rat subjected to transplacental administration of 7,12-dimethylbenz(a)anthracene. After ovarian cancer inoculation rats were randomized in four groups: i.p. administration of o.5 ml of saline (control group, n = 19); IPEP with saline heated at temperature 36-37 C (n = 11); HIPEP with saline heated at temperature 40.5-41.5 C (n = 14); i.p. administration of cisplatin in a maximum tolerated dose of 4 mg/kg of body weight (n = 12). These procedures were performed once in 48 hours after ovarian cancer inoculation. Antitumor effects of the treatment were estimated by increase in survival time (IST) comparing median survival time (MST) of rats in different groups.Results: MST of rats in the control group was 9 days (95% CI from 9 to 19). IST for IPEP and HIPEP were 78% (p = 0.307) and 150% (p = 0.006) correspondingly compared to the control group. IST for i.p. administration of cisplatin was 117% (p = 0.007) compared to the control group which was stronger than antitumor action of IPEP (p = 0.006) but comparable to the action of HIPEP (p = 0.38).Conclusion: Hyperthermia itself provides strong antitumor action comparable to the effect of i.p. administration of cisplatin while normothermic intraperitoneal perfusion has no significant influence on the survival of rats with advanced ovarian cancer.