Nicotinamide 500 mg twice daily was linked with fewer new keratinocyte skin cancers in veterans with prior disease, particularly squamous cell carcinoma when therapy began following the first cancer. Basal cell carcinoma rates did not change overall. The retrospective Veterans Affairs cohort included more than 33,000 patients. Limitations included reliance on administrative codes, potential misclassification of exposure, and a predominantly older White male population. Researchers noted that a randomized clinical trial is underway to confirm these findings.

Source: JAMA Dermatology