Oral vitamin D3 improves actinic keratosis response to PDT

Pretreatment with oral cholecalciferol (vitamin D3) results in significant improvements in clinical responses of actinic keratoses (AKs) to blue light photodynamic therapy (PDT), reports a study. In addition, the regimen is well tolerated by patients.

Mouse models of skin cancer have shown the beneficial effect of high-dose oral vitamin D2 plus PDT on the clearance of squamous precancers, such as AKs. In this study, the authors determined whether oral vitamin D3 can also improve the efficacy of a painless PDT regimen in humans with AK.

Patients were divided into two groups, and their baseline lesion counts and serum 25-hydroxyvitamin D3 levels were defined. In group 1, 29 participants underwent gentle debridement and 15-minute aminolevulinic acid preincubation with blue light (30 minutes; 20 J/cm²). In group 2, 29 patients received oral vitamin D3 (10,000 IU) daily for 5 or 14 days prior to debridement and PDT. The authors then assessed lesion clearance at 3 to 6 months.

The mean clearance rates of facial AK in group 1 were lower among patients with vitamin D3 deficiency (25-hydroxyvitamin D3 level <31 ng/dL; clearance rate, 40.9 percent) than in those with normal 25-hydroxyvitamin D3 levels (62.6 percent).

In group 2, supplementation with high-dose vitamin D3 significantly improved the overall AK lesion response relative to that in group 1 (72.5 percent vs 54.4 percent). No substantial between-group difference was seen in adverse effects.

This study was limited by its nonrandomized trial design (intervention cohort matched to registry-based controls), according to the authors.