EDITORIALS Genetic Control of Cancer Metastasis

Cancer is a complex of many types of malignant neoplastic growths, and each cancer of each organ exhibits numerous subsets. Despite this heterogeneity, malignant neoplasms have a uniform characteristic—the ability to invade host tissues and produce metastases. The most fearsome aspect of cancer is metastasis. This fear is well based. There have been great improvements in diagnosis, general patient care, surgical techniques, and local and systemic adjuvant therapies, but most deaths from cancer are still due to metastases that are resistant to conventional therapies. Continual empiricism is unlikely to produce significant improvement. Rather, a better understanding of the metastatic process and the development of biologic heterogeneity in neoplasms should provide a basis for new approaches to more effective therapy. Identification of specific properties unique to metastatic cells is an obvious prerequisite.