Laser-induced thermotherapy combined with hepatic arterial embolization inthe treatment of liver tumors in a rat tumor model

Objective To assess the effect of combined laser-induced thermotherapy (LITT) and hep atic arterial embolization with degradable starch microspheres (DSM) on tum or response and intrahepatic temperature distribution in rats with liver tu mors. Summary Background Data Laser-induced thermotherapy is a promising in situ ablation technique for m alignant liver tumors. However, clinical use is still limited, mainly becau se of the small size of the inducible coagulation necroses. This results in insufficient tumor destruction. Methods Colon carcinoma CC531 was implanted in 60 WAG rat livers. Fourteen days lat er, a silicon catheter was implanted in the hepatic artery for DSM administ ration. Tumors were exposed to 1064 nm Nd:YAG laser light at 2 watts for 10 minutes from a diffuser tip applicator placed in the tumor. The animals we re randomized into a sham-operated control (group I) and three test groups. Group ii received DSM alone, group III received LITT alone, and group IV r eceived DSM + LITT. Tumor control was examined 1, 7, and 14 days after trea tment. Results A complete tumor remission was achieved in all rats treated with LITT + DSM (group IV). In contrast, tumor progression was seen in animals treated wit h LITT alone (group III) or DSM alone (group II), as well as in the sham-op erated controls (group I). Conclusions The authors' results suggest that the combination of LITT and DSM considera bly increases the efficacy of LITT in the treatment of liver metastases in the rat.