Pressurized intraperitoneal aerosol chemotherapy (PIPAC) has been suggested as an alternative option for treating peritoneal carcinomatosis (PC). Even with its clinical advantages, the current PIPAC system still suffers from limitations regarding drug distribution area and penetration depth. Thus, we evaluated the new PIPAC system using a novel prototype, and compared its performance to the results from previous studies related with the current MIP^® indirectly because the system is currently not available for purchase in the market. The developed prototype includes a syringe pump, a nozzle, and controllers. Drug distribution was conducted using a methylene blue solution for performance test. For penetration depth evaluation, an ex-vivo experiment was performed with porcine tissues in a 3.5 L plastic box. Doxorubicin was sprayed using the novel prototype, and its penetration depth was investigated by confocal laser scanning microscopy. The experiment was repeated with varying nozzle levels from the bottom. The novel prototype sprays approximately 30 μm drug droplets at a flow rate of 30 mL/min with 7 bars of pressure. The average diameter of sprayed region with concentrated dye was 18.5 ± 1.2 cm, which was comparable to that of the current MIP^® (about 10 cm). The depth of concentrated diffusion (DCD) did not differ among varying nozzle levels, whereas the depth of maximal diffusion (DMD) decreased with increasing distance between the prototype and the bottom (mean values, 515.3 μm at 2 cm; 437.6 μm at 4 cm; 363.2 μm at 8 cm), which was comparable to those of the current MIP^® (about 350–500 μm). We developed a novel prototype that generate small droplets for drug aerosolization and that have a comparably wide sprayed area and depth of penetration to the current MIP^® at a lower pressure.

Aim: To establish an experimental system for comparing different methods of intraperitoneal chemotherapy in a rat model. Materials and Methods: We used six-week-old Sprague–Dawley rats, and created an early postoperative intraperitoneal chemotherapy (EPIC) system using 18-gauge syringes and evacuators, and a hyperthermic intraperitoneal chemotherapy (HIPEC) system using two peristaltic pumps which controlled the flow rate and temperature. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) was achieved using a nozzle for dispersing aerosols at a flow rate up to 41.5 ml/min. The distribution and intensity of 0.2% trypan blue dye was compared among three methods. Results: The distribution was limited and the intensity was weak after EPIC, and the dye stained moderately in gravity-dependent regions after HIPEC. On the other hand, the distribution was the most comprehensive, and the intensity was the greatest after PIPAC. Conclusion: This experimental system in a rat model may reflect the comparative effect among EPIC, HIPEC and PIPAC in humans.