LAUSR

BACKGROUND In mouse skin cancer models, high-dose oral vitamin D3 (VD3; cholecalciferol) combined with photodynamic therapy (PDT) can improve the clearance of squamous precancers (actinic keratoses, AK). OBJECTIVE To determine whether oral VD3 can improve clinical efficacy of a painless PDT regimen in humans with AK. METHODS Baseline lesion counts and serum 25OH-D3 levels were obtained. In one cohort (Group 1), 29 patients received gentle debridement and 15-min ALA preincubation followed by blue light (30 min; 20 J/cm2). In Group 2, 29 patients took oral VD3 (10,000 IU daily, 5 or 14 days) prior to the debridement/PDT. Lesion clearance was assessed at 3-6 months. RESULTS In Group 1, mean clearance rates (CR) of facial AK were lower in patients with VD3 deficiency (25OH-D3 <31 ng/dL; CR 40.9 ± 42%) than in patients with normal 25OH-D3 levels (62.6 ± 14.2%). High dose VD3 supplementation (Group 2) significantly improved overall AK lesion response (72.5 ± 13.6%) compared to Group 1 (54.4 ± 22.8%). No differences in side effects were noted. LIMITATIONS Nonrandomized trial design (interventional cohort matched to registry-based controls). CONCLUSION Oral VD3 pretreatment significantly improves AK clinical responses to PDT. The regimen appears promising and well tolerated.