Laser-induced hyperthermia in the treatment of liver tumors.

Seven patients with malignant liver tumors were treated with Nd:YAG laser induced hyperthermia. The laserthermia was performed during laparotomy using Nd:YAG laser with contact sapphire probes with power settings of 6 W. The contact tip was placed into the middle of the tumor and the temperature in 1.5-2.0 cm from the middle of the tumor was raised and held between 41C and 45C for ten minutes. One fatal complication appeared caused by an air embolism. In the postoperative fine needle biopsies on third and fifth postoperative day the sytologic finding in the tumor was necrosis. However, in 30% of the samples there was also a suspicion of cancer cells. In the computer tomography four weeks after the treatment there were also signs of necrosis. It seems that selective destruction of malignant liver tumors is possible with contact Nd:YAG laser induced hyperthermia.