Thalidomide is a synthetic derivative of glutamic acid with sedative-hypnotic 
activity, which caused devastating teratogenic effects in the 1960s. This paper 
reviews the possible mechanisms of its teratogenic effect, its new therapeutic 
indications, the proposed mechanisms for its antitumor activity and, finally, 
reviews published studies of its application in oncology. Current data 
demonstrates that thalidomide is clinically promising in multiple myeloma, 
glioblastoma multiforme and renal cell cancer. Furthermore, a beneficial effect 
of the drug has been proposed in cancer-related cachexia, which merits further 
investigation. Well-designed, randomized studies are warranted to establish the 
possible indications of thalidomide as an antitumor compound.