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Background Reproduction of the perfusion used in therapy (hyperthermic intraperitoneal chemotherapy) procedures preclinically represents a valuable asset for investigating new therapeutic agents that may improve patient outcomes. This article provides technical descriptions of our execution of closed and open “coliseum” abdominal perfusion techniques in a mouse model of peritoneal carcinomatosis of colorectal cancer. Materials and Methods BALB/c mice presenting with disseminated colorectal cancer (CT26-luciferin cells) underwent 30-min perfusions mimicking either the closed perfusion or the coliseum perfusion technique. Disease burden was monitored by bioluminescence signaling using an in vivo imaging system. Perfusion circuits consisted of single inflow lines with either a single or dual outflow line. Results Twelve mice presenting with disseminated disease underwent the closed perfusion technique. Surgical complications included perfusate leakage and organ constriction/suction into the outflow line(s). Nine mice underwent the coliseum perfusion technique with surgical debulking, using bipolar cauterization to remove tumors attached to the peritoneum. All mice survived the coliseum perfusion with limited intraoperative complications. Conclusions Fewer intraoperative complications were experienced with our coliseum perfusion technique than the closed perfusion. The methods described here can be used as a guideline for developing future perfusion murine models for investigating perfusion models useful for delivery of chemotherapy or other tumor-sensitization agents, including selective targeted agents, nanoparticles, and heat.

Background and Objective Photothermal therapy (PTT) has several applications in the areas of wound healing, pain management, bacterial infection control, and cancer treatment dependent on the temperature that is generated. PTT is often used exclusively with near infrared (NIR) light and most nanoparticles (NP) used for PTT are designed to absorb within one narrow range of wavelengths. We have developed a dual-wavelength photothermal therapy by capitalizing on the dual absorption of nanoparticles in the blue and NIR range. Materials and Methods Our lab has previously developed NP based on the semiconducting, conjugated polymer poly[4,4-bis(2-ethylhexyl)-cyclopenta[2,1-b;3,4-b′]dithiophene-2,6-diyl-alt-2,1,3-benzoselenadiazole-4,7-diyl] (PCPDTBSe). The NP have strong absorption in the blue and NIR regions. In this report, we have explored the heat generated by PCPDTBSe NP using simultaneous delivery of 450 and 800 nm light, either independently or together for photothermal ablation of mouse colorectal cancer cells. Results The heat generation studies indicated that the use of either 450 or 800 nm wavelengths at the same fluences produced approximately the same temperature change of deionized water. Fluences of 114.6 and 229.2 J/cm2, utilizing 450 or 800 nm light applied individually resulted in temperatures of 8–47°C above ambient temperature, leading to a 90% reduction in cell viability. Simultaneous stimulation of the PCPDTBSe NP with 450 and 800 nm light effectively doubles the effective power delivered, resulting in temperatures 18–63°C above ambient and 100% photothermal ablation of the colorectal cancer cells. Conclusion The results of this study demonstrate that PCPDTBSe polymer NP can be utilized as effective PTT agents by capitalizing on their dual absorption of both blue and NIR light. Lasers Surg. Med. © 2016 Wiley Periodicals, Inc.