[Local therapy of liver metastases of colorectal carcinomas. Laser therapy vs. direct current treatment in the rat model].
OBJECTIVE
Evaluation of the efficacy of direct current and laser therapy in the treatment of colorectal liver metastases in a rat model.


METHODS
Liver metastases in 49 rats were induced by subcapsular injection of cells of a colorectal tumor cell line. 3 weeks after inoculation 41 tumors were treated by laser and 56 tumors by direct current therapy. 17 tumors served as a control in the direct current group, 12 in the laser therapy group. The inoculation rate and the tumor size 3 and 5 weeks after therapy were determined by MRI.


RESULTS
The MR-tomographically determined inoculation rate was 133 tumors after 151 tumor cell injections (88%). Three and five weeks after laser therapy, tumor growth rates of 15% and 18% were documented (maximum tumor diameter). This represented a significant reduction in growth (p < or = 0.01 and p < or = 0.001) compared to the control group (growth rate 230% and 280%). In the direct current therapy group, growth rates were 40% after 3 and 60% after 5 weeks. Compared to the control group (210% and 290%), this also represented a significant reduction (p < or = 0.001).


CONCLUSIONS
This animal study is the first to demonstrate an antitumor effect of direct-current therapy on liver metastases of colorectal cancer in rats. Nevertheless, the laser therapy proved to be more effective.
Maintz
D
D
Institut und Poliklinik für Radiologische Diagnostik, Medizinische Einrichtungen der Universität zu Köln. maintz@uni-muenster.de
Fischbach
R
R
Schäfer
N
N
Türler
A
A
Kugel
H
H
Schäfer
H
H
Lackner
K
K
D000818:Animals; D002455:Cell Division / Q000502:physiology; D015179:Colorectal Neoplasms / Q000473:pathology / Q000601:surgery*; D004564:Electrocoagulation; D017075:Laser Coagulation; D008099:Liver / Q000473:pathology; D008114:Liver Neoplasms, Experimental / Q000473:pathology / Q000556:secondary* / Q000601:surgery; D009368:Neoplasm Transplantation; D051381:Rats; D014407:Tumor Cells, Cultured