Therapeutic effects of endoscopic ultrasound-guided holmium laser ablation for pancreatic primary implantation carcinoma in nude mice

Objective To explore the effectiveness of endoscopic ultrasound(EUS)-guided holmium laser ablation for primary pancreatic implantation tumor in nude mice. Methods Pancreatic cancer cell line SW1990 were implanted into 20 4-6-week-old male balb/c nude mice to establish primary pancreatic implantation tumor in situ models. Then the nude mice were randomly divided into two groups, the treatment group(n=10) and the control group(n=10). The treatment group underwent EUS-guided holmium laser ablation in the pancreatic tumor. And no interventions were given to the control group. The volume of tumors of the two groups were measured under EUS at time points of 7 d, 14 d and 28 d after ablation. The activities, appetites and psychosis of all nude mice were evaluated in the meantime. At 28 d after ablation, lesions of pancreas were dissected and sliced for H&E staining. Results There were no complications in the treatment group, and all nude mice could tolerate the procedure. The mental state, activities and appetites of nude mice in the experimental group were better than those in the control group. Tumors of the control group enlarged. There was significant difference in the tumor size between the two groups at 28 d after ablation. HE staining showed coagulation necrosis in the ablation area. Conclusion EUS-guided holmium laser, producing coagulative necrosis in the ablation area, is effective for primary pancreatic implantation carcinoma in nude mice for about 28 days. Key words: Ultrasonography; Laser therapy, Holmium; Disease modelsl; Rats, nude