Synergistic effect of hyperthermic chemotherapy with extract of Caucalis platycarpos on survival rate of mice with peritoneal carcinomatosis.

Background/aims: Peritoneal carcinomatosis is prognostically a very bad sign and common cause of death in patients with intestinal and stomach carcinoma as well as other gastrointestinal and gynecologic tumors. During a tumor surgery risk of peritoneal carcinomatosis is high because tumor cells are "dropping off" from the tumor surface which infiltrates serosa of abdominal cavity in which it has been developed, so iatrogen peritoneal carcinomatosis develops. The aim of this study was to explore and compare different models of locoregional immunochemotherapy, hyperthermial intraperitonal chemotherapy (HIPEC) in unique animal model of induced peritoneal carcinomatosis in mice. Material and methods: CBA mice were injected with mammary carcinoma (MCa) cells into abdominal cavity and consecutive peritoneal carcinomatosis was induced. In so called prevention model biological response modifiers (BRM), plant extract from Caucalis platycarpos (CDL) at dose of 200 mg kg-1 was injected into abdominal cavity seven and three days before injection of tumor cells, respectively. Immediately after the injection of tumor cells we rinsed abdominal cavity with saline that was heated to 37°C or 43°C (hyperthermial treatment) and injected cytostatics: doxorubicin (DOX) 20 mg kg-1, cisplatin (CIS) 10 mg kg-1, mitomicyn (MIT) 5 mg kg-1, 5- fluorouracil (5-FU) 150 mg kg-1 either separately or in combination. In therapeutic model BRMs were injected on day 5th after injection of tumor cells. Hyperthermia treatment was performed immediately before injection of cytostatic drugs. Results: Combination of doxorubicin and plant extract CDL was very effective in prevention consindering survival and pathological signs of peritoneal carcinomatosis. Doxorubicin as a drug of choice alone or in combination with either CDL or 5-FU or cisplatin with reinforced influence caused by hyperthermia, popped up among therapy models. Conclusion: These investigations suggest the synergistic effect of hyperthermia, chemotherapy and immunotherapy with plant extract from Caucalis pltycarpos. The possible mechanism of this treatment should be investigated.