SIGNIFICANCE OF ANGIOGENESIS IN CANCER-THERAPY

Background For most solid tumours, surgery remains the most effective primary treatment. Despite apparently curative resection, significant numbers of patients develop secondary disease due to growth of undetec ted micrometastases. The ability of a tumour to metastasize is related to the degree of angiogenesis it induces. In addition, micrometastase s rely on new vessel formation to provide the nutrients necessary for growth. A better understanding of how tumours acquire their blood supp ly may lead to more effective adjuvant therapies and improve survival following surgery. Methods A systematic review of the literature on an giogenesis between 1971 and 1997 was performed using the Medline datab ase to ascertain current thinking on angiogenesis and its relevance in oncological surgery. Results Angiogenesis is a physiological process subject to autocrine and paracrine regulation which has the potential to become abnormal and play a part in a number of pathological states, including cancer. Increased angiogenic stimuli in the perioperative p eriod, associated with concomitant reduction in tumour-derived antiang iogenic factors following resection of a primary tumour, result in a p ermissive environment which allows micrometastases to grow. Conclusion Recognition of the role of angiogenesis in metastatic tumour growth r epresents a significant development in our understanding of tumour bio logy. The development of antiangiogenic agents offers new promise in t he treatment of malignancy. Such agents may prevent or control the dev elopment and growth of primary and metastatic tumours.