Chemoprevention has been shown to be an extremely promising approach t
o the prevention of invasive cancer. Through the identification of che
mopreventive agents that inhibit or reverse the process of carcinogene
sis, new strategies of early intervention can be developed for patient
s at high risk that potentially prevent the onset of invasive and meta
static phases of cancer. This articles reviews the present efforts in
chemoprevention research, including the identification of promising ag
ents, screening, and preclinical and clinical evaluations.