Laser ablation of pancreatic cancer using a cylindrical light diffuser.

Pancreatic cancer (PC) is a leading cause of cancer death and its incidence and mortality have shown an increasing trend. Despite improvements in outcomes, another treatment option is required for PC. Laser ablation (LA) has been evaluated for the treatment of various types of cancer. The aim of this study was to assess the safety and feasibility of a novel cylindrical light diffuser in a xenograft model of PC. This study was performed using a customized high-power laser system. PANC-1 cells and BALB/c mice were used for experiments at a laser power of 5 W for 40 to 200 s at five different energy levels (n = 30). There was no acute bleeding or major complication. Using the cylindrical light diffuser, tumors were irradiated with similar size in each energy group. A correlation between laser dose and tumor necrosis was observed. Pearson's correlation for the relation between the amount of necrosis area and laser ablation energy on day 3 was 0.78 (p < 0.01). No statistical difference of necrosis area was exhibited when the necrosis area of each harvested tumor analyzed by dividing into 5 specimens for each energy. The study demonstrates that LA treatment using a cylindrical light diffuser induced remarkable tumor necrosis at histopathologic examinations. Laser ablation dosage and tumor response were strongly correlated, and the ablation procedure resulted in homogeneous tissue necrosis. No adverse event was encountered. These findings suggest that the devised cylindrical light diffuser offers a safe and effective means of treating pancreatic cancer.