Angiogenesis in pre-invasive cancers

To date, research in the role of angiogenesis in cancer has focused mainly on invasive diseases. Measurement of the intra-tumoural microvessel density (MVD) has also been found to be an independent prognostic marker. More recently, natural angiogenic inhibitors and pharmacological drugs capable of suppressing specific stages of neovascularisation have been reported.

This review article concentrates on those angiogenesis-related findings in pre-invasive disease.

The study of angiogenesis in early and preneoplastic lesions is still at a preliminary stage. Current work provides indirect evidence, either from clinical or experimental studies only, most of which have used animal models. The use of the MVD as a marker of potential tumour invasion in pre-neoplastic disease is an attractive proposition. However, its prognostic values remain to be evaluated. Measurement of angiogenic factors, or their expression in certain pre-malignant conditions, may provide further information as to which disease may become invasive, and could possibly be used as a follow-up tool. The current treatment of pre-malignant conditions is usually surgical, although the early results of anti-angiogenesis therapy in animal models show encouraging results. Prevention is always better than cure, and the identification of pre-malignant lesions with intervention to prevent malignant transformation may soon become a realistic goal.