Photodynamic therapy for actinic keratosis followed by 5-fluorouracil reaction

Actinic or solar keratoses are the earliest form of cancerous lesions that are found in sun-exposed areas of the body. Treatment involves eliminating the lesions before they have a chance to progress. Mainstay therapies include curettage, cryosurgery, and topical 5-fluorouracil. A recently Food and Drug Administration-approved regime using photodynamic therapy has also been employed since 2000.

To inform physicians of the efficacy and potential inefficiency of this procedure, enabling the assessment of proper placement in the armamentarium.

This patient underwent photodynamic therapy. She was challenged with 5-fluorouracil 5 weeks after photodynamic treatment.

The patient responded well to the photodynamic therapy and also to the challenge with the 5-fluorouracil.

Did the photodynamic treatment really destroy lesions significantly? What is the mechanism for the response to 5-fluorouracil after such a short period between treatment modalities? If 33% of patients treated with photodynamic therapy require retreatment in 8 weeks, is this modality cost-effective, and what is its place in treating patients? How should this new treatment be implemented in practice? These questions must be seriously assessed.