Interstitial laser thermotherapy of a rat liver tumour: effect of hepatic inflow occlusion.
OBJECTIVE
Interstitial laser thermotherapy was used to treat rat liver tumours. The aim was to investigate the influence of temperature and temporary hepatic inflow occlusion on tumour growth and blood perfusion.


METHODS
Liver tumours were treated at 44°C at the tumour border for 30 minutes, hepatic inflow occlusion only, or a combination of these methods. Interstitial laser Doppler flowmetry was used to measure hepatic perfusion at the tumour border during and after heat treatment, for a total time of 60 minutes. Tumour growth was evaluated 6 days after treatment.


RESULTS
Tumours subjected to the combined treatment of hepatic inflow occlusion and interstitial laser thermotherapy displayed a blood perfusion reduction 30 minutes after treatment to 18 ± 5% of initial perfusion, which was significantly lower than achieved with thermotherapy alone (52 ± 10%, P = 0.02). The combined treatment and treatment with thermotherapy alone resulted in relative tumour growth of 0.3 ± 0.1 and 1.0 ± 0.2, respectively (P = 0.04).


CONCLUSIONS
Inflow occlusion enhanced the effect of thermotherapy not by augmenting treatment temperatures but by increasing the thermal sensitivity of the tumour, reflected by an immediate effect on tumour blood perfusion.
Department of Surgery, Clinical Sciences Lund, Lund University, SE-221 85 Lund, Sweden. christian.sturesson@skane.se
Christian
C
Sturesson
Kjell
K
Ivarsson
Unne
U
Stenram
Stefan
S
Andersson-Engels
Karl-Göran
KG
Tranberg
D000818:Animals; D006979:Hyperthermia, Induced / Q000379:methods*; D053685:Laser Therapy; D008113:Liver Neoplasms / Q000098:blood supply* / Q000628:therapy*; D008297:Male; D051381:Rats; D017208:Rats, Wistar