It is estimated that in 2005 there were 17,550 new cases of liver and biliary cancer in the U.S. and 15,420 cancer related deaths. In the world, 626,162 new cases were diagnosed in 2002, 2/3 of them in East Asia. Five-year relative survival rates for liver and biliary cancers are about 9%. Although surgical resection is a preferred treatment for liver cancer, only 20% of patients are candidates. Chemotherapy, chemoembolization, alcohol ablation, radiofrequency ablation, and cryoablation are alternatives to resection. Recent attempts to use stereotactic body radiation therapy have resulted in successful tumor control as well.3
Using the CyberKnife® System to treat liver cancer
Thus far, in the treatment of liver tumors, centers have treated with the CyberKnife® System alone or in combination with transhepatic arterial chemoembolization. Single-fraction approaches have achieved local control with a dose of 25 Gy.4 Other centers have treated with three fractions to a total dose of 30-39 Gy, with just a few mild side effects noted.5 With the introduction of the Synchrony® Respiratory Tracking System, clinicians are better able to track hepatic tumors which move with respiration thus limiting dose to the tumor and minimizing dose to healthy adjacent liver tissue.
References
1.Jemal A, Murray T, Ward E, Samuels A, Tiwari RC, Ghafoor A, et al. Cancer statistics, 2005. CA Cancer J Clin 2005;55(1):10-30. PubMed ABSTRACT
2.International Agency for Research on Cancer. GLOBOCAN 2002 Database Lyon, France, 2002.
http://www-dep.iarc.fr/globocan/database.htm
3.Grover A, Alexander HR, Jr. The past decade of experience with isolated hepatic perfusion. Oncologist 2004;9(6):653-64. PubMed ABSTRACT
4.Choi IB, Choi BO, Ryu MR, Kang YN, Hahn ST, Han JY, et al. CyberKnife® management of primary hepatocellular carcinoma. In: Mould RR, Bucholz RD, Gagnon GJ, et al., eds. Robotic Radiosurgery Sunnyvale, CA: CyberKnife® Society Press, 2005:279-86.
5.Lieskovsky YC, Koong A, Fisher G, Yang G: Phase I Dose Escalation Study of CyberKnife® Stereotactic Radiosurgery for Liver Malignancies Meeting of the So Thoracic Surgery Association 2005