Control of malignant metastases by ICRF l59.

Abstract

THE aim of cancer chemotherapy to destroy the last malignant cell may be unnecessarily ambitious if inhibition of metastases formation by chemotherapy could convert a malignant to a quasi-benign tumour. Systematic investigations into the experimental chemotherapy of spontaneous metastases have, however, been remarkably few1. This is perhaps not surprising in view of the technical difficulties experienced in the past in obtaining meaningful results. We have for some time attempted to study the effects of potential anticancer agents on the development of metastases by using the Lewis lung (3LL) tumour of mice, a tumour which produces metastases regularly, spontaneously and consistently to give multiple lung metastases2–4. We have attempted to do this not only because the ability to invade adjacent tissues is riot shared by most normal dividing tissues5, but also because it seems entirely possible that the basic processes of secondary tumour formation—invasion, dissemination and implantation—may have similar biochemical and biophysical characteristics in most malignant tumours.