Invasion and metastasis.

Tumor metastasis remains a major cause of death for cancer patients. From a clinical perspective, treatment of metastatic disease remains difficult. The initial tumor cell invasive and locomotive events have been completed in many patients by the time of cancer diagnosis and surgery. This observation focuses attention on the last steps in the metastatic cascade for therapeutic development, ie, angiogenesis and colonization at the metastatic site. Emerging themes in metastasis research, including the molecular characterization of protease production and angiogenesis, the interrelationship of growth and metastasis, and the genetic control of the metastatic process are discussed.