Photodynamic Therapy vs. Topical Chemotherapy for Actinic Keratoses: Which is Right for You?
Actinic keratoses (AKs) are a common dermatological concern, often appearing as rough, scaly patches caused by prolonged sun exposure. While most AKs never progress to skin cancer, some can progress to squamous cell carcinoma, making preventative treatment a recommended medical procedure. For patients with numerous actinic keratoses, your dermatologist may recommend field-directed therapy, in which a broad area is treated of skin (such as the face or scalp) is treated at once. Two popular options for field-directed therapy are photodynamic therapy (PDT) and topical chemotherapy with 5% fluorouracil cream. Here’s a breakdown of these treatments to help you make an informed decision.
What is Photodynamic Therapy (PDT)?
PDT combines a photosensitizing agent, such as aminolevulinic acid (ALA), with a specific light source to destroy precancerous cells selectively. The process involves applying the agent to the skin, allowing it to penetrate for several hours, and then activating it with light. This activation produces reactive oxygen species that target and destroy abnormal cells.
What is Topical Chemotherapy?
5% fluorouracil is a topical cream that works by interfering with DNA synthesis in rapidly dividing cells. Applied daily for several weeks, it treats visible actinic keratoses while also targeting subclinical lesions (those not yet visible). This dual action makes it a powerful tool for field cancerization.
Comparing Efficacy
Both treatments are effective for field-directed therapy, but studies highlight differences in outcomes:
• Photodynamic Therapy (PDT): European studies report impressive clearance rates of up to 91% at 12 weeks when using red light and a 10% aminolevulinic acid (ALA) nanoemulsion. Similarly, U.S. trials with 20% ALA solution and blue light showed 73% complete clearance at 12 weeks. These results make PDT a highly effective option for rapid treatment and visible improvement.
• 5% Fluorouracil: Long-term studies show that fluorouracil achieved a 75% or greater reduction in lesions in 74.7% of patients at 12 months, making it the most effective option for sustained lesion clearance over time.
Side Effects
• PDT: Patients often report a "sunburn-like" reaction with redness, peeling, and some discomfort during light exposure. The downtime is generally shorter, with most symptoms resolving within a week.
• Fluorouracil: This treatment can cause significant inflammation, redness, and crusting as it works. While these effects are temporary, they can last several weeks and require patients to plan ahead.
Convenience
• PDT: Typically performed in-office, PDT requires fewer treatment sessions but may involve light sensitivity precautions for 48 hours after treatment.
• Fluorouracil: Applied at home, this option requires strict adherence to a daily regimen for 2-4 weeks. Patients must also prepare for an extended healing process.
Choosing the Right Option
The choice between PDT and topical chemotherapy often depends on your unique needs:
• Consider PDT if you prioritize cosmetic outcomes and prefer fewer in-office visits.
• Consider fluorouracil if you want the most effective option for long-term lesion clearance and are prepared for a longer treatment and healing process.
Final Thoughts
Both photodynamic therapy and topical fluorouracil are valuable tools in the fight against actinic keratoses. A consultation with your dermatologist can help you determine which treatment aligns best with your skin type, lifestyle, and goals.
At Pure Dermatology, we tailor treatment plans to each patient’s needs, ensuring the best possible outcomes. Contact us today to schedule your appointment and take the first step toward healthier, sun-damage-free skin.
