High intra-abdominal pressure enhances the penetration and antitumor effect of intraperitoneal cisplatin on experimental peritoneal carcinomatosis.

OBJECTIVE: To investigate the role of increased intra-abdominal pressure (IAP) on the intratumoral accumulation and the antitumor effect of intraperitoneal cisplatin in rats with advanced peritoneal carcinomatosis. To evaluate the tolerance of IAP in pigs, as it is a large animal with a body size equivalent to humans. SUMMARY BACKGROUND DATA: To investigate if an active convection, driven by a positive IAP, increases cisplatin penetration and antitumor effectiveness in a model of advanced peritoneal carcinomatosis in rats. EXPERIMENTAL DESIGN: BDIX rats with macroscopic peritoneal tumors received cisplatin administered as intravenous injection (IV), conventional intraperitoneal injection (IP), or sustained intraperitoneal injection of cisplatin given in a large volume of solvent for maintaining IAP for 1 hour. Platinum tissue concentration was measured by atomic absorption spectroscopy (AAS), and platinum distribution into the tumor nodules was assessed by the particular-induced x-ray emission (PIXE) method. The antitumor effect was assessed in a survival experiment. The hemodynamic, local, and systemic tolerance of IAP, with or without cisplatin, was evaluated in Large White pigs. RESULTS: The maximum tolerated IAP was 22 mm Hg for 1 hour in nonventilated rats. IAP, in comparison with IV or conventional IP injections, resulted in the increased concentration and depth of diffusion of platinum into diaphragm and peritoneal tumor nodules. Consequently, IAP treatment induced an extended survival of rats treated at an advanced stage of carcinomatosis. In 7 50- to 70-kg ventilated pigs, a 40-mm Hg IAP was well tolerated when maintained stable for 2 hours. Renal failure occurred in pigs receiving a total dose of 200 and 400 mg of cisplatin with IAP, but a dose of 100 mg was well tolerated. CONCLUSIONS: Intraperitoneal chemotherapy with increased IAP, in comparison with conventional IP or IV chemotherapy, improved the tumor accumulation and the antitumor effect of cisplatin in rats bearing advanced peritoneal carcinomatosis. In preclinical conditions, the tolerance of sustained IAP was manageable in ventilated pigs.

Prevention of peritoneal carcinomatosis from colon cancer cell seeding using a pirarubicin solution in rats and nude mice.

Free malignant cells, which are frequently detected in the washing liquid from the peritoneal cavity before and after resection of human colorectal cancer, are suspected to cause recurrent peritoneal cancer. We carried out an experimental study to compare the prophylactic efficacy of washing the peritoneum with several anticancer drugs and the antiseptic povidone-iodine against the development of peritoneal carcinomatosis from colonic origin in rats and nude mice. The in vitro anticancer activity of a short, 15-minute exposure of pirarubicin, doxorubicin, 5-fluorouracil, cisplatin, mitomycin C, and 1% povidone-iodine was first evaluated by an MTT assay on DHD/K12/PROb rat and LS174T human colon cancer cells. For the in vivo experiments, BDIX rats were inoculated intraperitoneally (i.p.) with 1 x 10(6) DHD/K12/PROb cells followed by peritoneal scarring and a colocolic anastomosis. A 15-minute peritoneal washing with the anticancer drugs or povidone-iodine was then performed. Nude mice were i.p.-inoculated with 1 x 10(7) LS174T human cells and treated 2 hours later with i.p. pirarubicin. Only pirarubicin, mitomycin C, and povidone-iodine were fully cytotoxic in vitro against DHD/K12/PROb rat colon cancer cells. In contrast to pirarubicin and povidone-iodine, mitomycin C was not completely active against LS174Tcells. In vivo, pirarubicin cured DHD/K12/PROb-inoculated rats, even at the site of the peritoneal scarring and intestinal anastomosis. i.p. pirarubicin prevented the development of peritoneal carcinomatosis and liver metastasis in LS174T-inoculated mice. i.p. washing with pirarubicin cured 2-day-old, but not 7-day-old, peritoneal carcinomatosis in rats. Short exposure to i.p. pirarubicin is nontoxic and more active than povidone-iodine and other anticancer drugs in preventing the development of peritoneal carcinomatosis from colonic origin in rats and mice. The prophylactic effect of preoperative peritoneal washing with pirarubicin on the development of recurrent peritoneal cancer should be evaluated in a randomized clinical trial.