VITAMINS AND CANCER CHEMOPREVENTION

Chemoprevention is in an area of cancer research with perhaps the grea test potential for reducing cancer mortality. Several agents, and in p articular antioxidant vitamins, appear to be effective against early r ather than later steps of the premalignant process at different sites, Particular attention must be paid to possible side effects and safety of the agents and to optimal doses in long-term administration regime ns, The results of numerous trials on the preventive role of vitamins (e.g, beta-carotene, retinols, retinoids, alpha-tocopherol, ascorbic a cid, folic acid) are contradictory and far from conclusive, Multiple p rimary and secondary intervention trials currently under way should as sess in the coming years the role of some vitamins in the prevention o f various cancers (oral cavity, pharynx, oesophagus, colon, lung, brea st, skin, cervix, bladder).