Interstitial laser thermotherapy of adenocarcinoma transplanted into rat liver

Eur J Surg. 1997 Nov;163(11):861-70.

Abstract

Objective: To examine the effect of different temperatures and exposure times in interstitial laser thermotherapy.

Design: Controlled laboratory study.

Setting: University hospital, Sweden.

Material: 48 male Wistar FU rats with dimethylhydrazine-induced adenocarcinoma transplanted into the liver.

Intervention: Treatment was given with an Nd:YAG laser and a feedback system for temperature regulation. Light was delivered into the centre of the tumour and the feedback thermistor probe was placed 3 mm from the tumour margin. Rats were treated at steady-state temperatures at the feedback thermistor of 43, 46, or 50 degrees C for 30 minutes, and at a steady-state temperature of 46 degrees C at the feedback thermistor also for 10 and 20 minutes.

Main outcome measurement: Tumour control as assessed 6 days after treatment using light microscopical examination including immunohistochemical determination of bromodeoxyuridine (BrdU) incorporation into DNA as a measure of cell viability.

Results: Complete tumour necrosis was achieved in all rats treated for 30 minutes, in 6/8 rats treated for 10 minutes and in 6/8 rats treated for 20 minutes at 46 degrees C. During steady-state thermotherapy, temperatures at the tumour margin were about 11 degrees higher than at the feedback thermistor (range 54-61 degrees C). The surrounding liver tissue also became necrotic so that the total necrosis volume exceeded the pretreatment tumour volume.

Conclusion: Interstitial laser thermotherapy at temperatures ranging from 54-61 degrees C at the tumour margin ensures total necrosis of a transplanted rat liver carcinoma provided that treatment is given for 30 minutes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / pathology
  • Adenocarcinoma / therapy*
  • Animals
  • Hyperthermia, Induced* / methods
  • Lasers
  • Liver Neoplasms, Experimental / pathology
  • Liver Neoplasms, Experimental / therapy*
  • Male
  • Necrosis
  • Neoplasm Transplantation
  • Rats
  • Rats, Wistar