Experimental study on interventional therapy of~(32)P chromic phosphate colloids for human pancreatic cancer(Pc-3)bearing nude mice

Objective To study the biodistribution in the tumor-bearing nude mice after intratumoral injection of 32P colloids and its effectiveness in the treatment of pancreatic cancer(Pc-3).Methods 54 tumor-bearing mice were divided into 9 groups(n=6) at random.The mice of group 1 to 3 were intratumoral injected 14.8 MBq 32P colloids and killed after 12,24,72 h,respectively.The mice of 4 to 9 were injected 3.7,7.4,14.8,18.5,29.6 and 0 MBq 32P colloids,and killed after 14 days.The radioactive distribution in mice body(%,ID/g),morphological changes,tumor growth inhibition rate,and PI (proliferation index) were determined through microspectroscopy,electromicroscopy and immunochemistry.Results Intratumoral administration of 32P colloids makes high level of radioactivity retained in the tumor for a long time.The tumor growth inhibition rate was 20.8%,38.3%,50.7%,70.2%and82.3% respectively(F=261.34,P0.01).PI was 70.2%,65.2%,45.2%,20.2%,10.3% and 92.0% (F=375.32,P0.01).Conclusion It is demonstrated that the intratumoral injection of 32P colloids is a safe and effective interventional therapy for pancreatic tumor.