A Phase 3 Randomized Trial of Nicotinamide for Skin-Cancer Chemoprevention

Among patients with a history of skin cancer, nicotinamide treatment was associated with a 23% lower rate of new nonmelanoma (basal-cell and squamous-cell) skin cancers than placebo, resulted in 13% fewer actinic keratoses after 12 months, and had similar adverse effects. Nonmelanoma skin cancers, mainly basal-cell carcinomas and squamous-cell carcinomas, are the most common cancers in white populations. 1 In Australia, nonmelanoma skin cancers are four times as common as all other cancers combined, 2 , 3 and in the United States, the annual total cost of treating nonmelanoma skin cancers is estimated to be $4.8 billion. 4 Basal-cell carcinomas rarely metastasize but are locally invasive and can be disfiguring. 5 Squamous-cell carcinomas, especially less well-differentiated tumors on the head and neck, have metastatic potential and may originate from premalignant actinic keratoses. 6 Nonmelanoma skin cancers and actinic keratoses are caused primarily by exposure to ultraviolet (UV) . . .