Effect of whole-abdominal irradiation on penetration depth of doxorubicin in normal tissue after pressurized intraperitoneal aerosol chemotherapy (PIPAC) in a post-mortem swine model

BACKGROUND This study was performed to evaluate the impact of whole-abdominal irradiation on local penetration of doxorubicin into the peritoneum and the abdominal organs in a post-mortem swine model. MATERIALS AND METHODS Doxorubicin was aerosolized into the abdominal cavity of swine at a pressure of 12 mmHg CO2 at room temperature (25°). One swine was subjected to pressurized intraperitoneal aerosol chemotherapy (PIPAC) using Micropump© without irradiation; the second one received 2 Gy and the third one 7 Gy whole-abdominal irradiation, 15 min prior to PIPAC application. Samples of the peritoneal surface were extracted at different positions from within the abdominal cavity. In-tissue doxorubicin penetration was measured using fluorescence microscopy on frozen thin sections. RESULTS The depth of penetration of doxorubicin was found to be wide-ranging, between 17 μm on the surface of the stomach and 348 μm in the small intestine. The penetration depth into the small intestine was 348 μm, 312 μm and 265 μm for PIPAC alone, PIPAC with 2 Gy irradiation and PIPAC with 7 Gy irradiation, respectively (p