Calcitriol and isotretinoin combined therapy for precancerous and cancerous skin lesions

Abstract

Calcitriol and retinoids regulate the growth and differentiation of many types of cells. These compounds exert their effects via nuclear receptors belonging to the steroid/thyroid hormone receptor. The combination of retinoids and vitamin D, exerts a synergistic effect on the differentiation of some tumour cells in vitro. The combination of these compounds has been reported to have a favourable effect on cutaneous T-cell lymphoma. We present the results of combined therapy in 11 cases of multiple actinic keratoses with signs of malignant transformation, Bowen's disease, squamous cell carcinomas (SCC) and basal cell carcinomas. The daily dosage of 13-cts-retinoic acid was 0.3-0.5 mg/kg, and of calcitriol 0.5 - 1 /ig used for many months. In one patient with multiple actinic keratoses and early SCCs a complete clearing was achieved after 15 months of therapy. In 9 of 11 patients during 5-14 months of treatment the lesions decreased by 30-85% in size and/or number. In one patient with multiple large SCCs the treatment was discontinued after 3 months because of lack of response. There were no significant side-effects. This experimental therapy could find application for patients with multiple, widespread early cutaneous nonmelanoma skin cancers, which are too abundant to be treated with standard procedures, and for tumour prevention. (/ Dermatol Treat (1997) 8: 5-10)

Key Words:

• Retinoids
• Vitamin D
• Skin cancers