A tumor that has spread from its original (primary) site of growth to another site, close to or distant from the primary site. metastasis is characteristic of advanced malignancies, but in rare instances can be seen in neoplasms lacking malignant morphology. check for "https://www.cancer.gov/about-cancer/treatment/clinical-trials/intervention/c3261" active clinical trials using this agent. ("http://ncit.nci.nih.gov/ncitbrowser/conceptreport.jsp?dictionary=nci%20thesaurus&code=c3261" nci thesaurus)