Abstracts
1997 Digestive Disease Week

Laser-induced thermotherapy for the palliative treatment of malignant liver tumors - results of a clinical study.

D Albrecht, CTh Germer, C Isbert, J Ritz, A Roggan, HJ Buhr. Department of Surgery, UK Benjamin Franklin, Freie Universitat Berlin, Germany.

Indroduction: Laser-induced thermotherapy (LITT) is a local hyperthermic procedure for the treatment of malignant liver tumors. The aim of the study was to investigate, whether local control of tumor growth can be achieved with this method and whether method-related complications occur. In a clinical pilot study, Laser-induced thermotherapy was applied in patients, for whom other established treatment methods were no longer an option. Material and methods: The laser-induced thermotherapy was performed using a ND:YAG laser at a wavelength of 1064 nm. A new developed diffusing fiber tip was used with an distal output power of 5 - 8 W. The exposure time was 840 s. The application system was placed in the tumor tissue either percutaneously under CT guidance or during laparotomy under ultrasound control. Magnetic resonance tomography served as the on-line monitoring procedure for percutaneous application and B-scan ultrasound during surgery. Follow-up after therapy was done with computerized tomography. Results: A total of 20 patients aged 45 - 85 years were treated. 10 patients had metastases from a colorectal carcinoma, 8 a hepto- or cholangiocarcinoma, 1 a renal cell and 1 a parotid carcinoma. Laser application was performed percutaneously in 6 cases and during laparotomy in 14. Complications included pleural effusion in 4 patients and a bile fistula in 2. In the follow-up period of 3 - 26 months, 11 patients had no new tumor growth. In 9 patients, new tumor growth outside of the hyperthermic area or extrahepatic metastatic spread was seen after 2 - 11 months. Conclusion: LITT can be applied both percutaneously and by laparotomy with low morbidity. Local control of tumor growth can achieved in completely treated tumors. Evaluation of the method with regard to a prognostic gain for the treated patients is not possible at this time.