Linomide improves the effect of interstitial laser thermotherapy in a rat liver tumour model

Aim: The aim of this study was to investigate if Linomide affects growth and spread of a rat liver tumour when given alone and in combination with interstitial laser thermotherapy (ILT). Materials and Methods: Experiments were performed in Wistar rats using a dimethyl-hydrazine-induced adenocarcinoma implanted into the left lateral lobe of the liver. The rats were randomised to one of the following groups: a) ILT and Linomide, b) ILT only, c) sham ILT, d) Linomide only, or e) control. ILT was intentionally suboptimal. Linomide (100 mg/kg/day) was given in the drinking water from the start of treatment for five (lays. ED1, ED2 macrophages and v Willebrand (factor VIII) were determined by an immunohistochemical technique. Results: Linomide reduced viable liver tumour volume both when it was given alone (p < 0.01) and when combined with ILT (p < 0.05), whereas it lowered intraperitoneal spread in ILT-treated rats alone. Six days after ILT there was a reduction in the number of newly-recruited macrophages and blood vessels in the viable tumour tissue in rats receiving Linomide. Conclusion: Linomide reduced the growth of an adenocarcinoma transplanted into rat liver, when given alone or combined with laser thermotherapy and reduced the spread of tumour in laser-treated rats. The effects of Linomide in laser-treated rats appeared, at least in part, to be due to a reduction in newly-formed vessels, which might have been secondary: to a reduced number of tumour-associated macrophages.