What is the cure rate of superficial basal cell carcinoma (BCC) with photodynamic therapy (PDT) versus daylight PDT?

From the Guidelines

Conventional photodynamic therapy (PDT) is generally preferred over daylight PDT (dPDT) for treating superficial basal cell carcinoma (sBCC) due to its higher cure rates, with reported cure rates of approximately 80-90% for superficial BCC at 3-month follow-up, as compared to daylight PDT which shows slightly lower efficacy with cure rates of approximately 70-80% for superficial BCC 1.

Key Points

• Conventional PDT involves application of a photosensitizer (typically aminolevulinic acid or methyl aminolevulinate) followed by illumination with a specific wavelength artificial light source at precise doses.
• Daylight PDT uses natural sunlight as the light source, which is more convenient and causes less pain but provides variable light intensity depending on weather conditions, geographic location, and season.
• The difference in efficacy is attributed to the controlled light delivery and higher cumulative light dose in conventional PDT.
• For optimal outcomes with superficial BCC, conventional PDT is generally preferred, particularly for higher-risk areas or when maximum efficacy is required.
• However, daylight PDT remains a reasonable alternative for patients who cannot tolerate the pain associated with conventional PDT or when accessibility to specialized equipment is limited.

Cure Rates

• Conventional PDT: approximately 80-90% for superficial BCC at 3-month follow-up, with long-term complete response rates around 70-75% at 5 years.
• Daylight PDT: approximately 70-80% for superficial BCC.

Recommendations

• Conventional PDT is recommended for patients with superficial BCC who require maximum efficacy and can tolerate the potential pain associated with the treatment.
• Daylight PDT is recommended for patients who cannot tolerate the pain associated with conventional PDT or when accessibility to specialized equipment is limited.

Evidence

• The guidelines for topical photodynamic therapy: update, published in the British Journal of Dermatology in 2008, reported a weighted clearance rate of 87% for superficial BCC with ALA-PDT 1.
• The british association of dermatologists and british photodermatology group guidelines for topical photodynamic therapy 2018, published in the British Journal of Dermatology in 2019, recommended clearance rates of ≥ 75% of AK, SCC in situ and superficial BCC lesions (including daylight PDT for individual AK lesions or field areas) 1.

From the Research

Cure Rate of Superficial BCC with PDT versus Daylight PDT

• The cure rate of superficial basal cell carcinoma (BCC) with photodynamic therapy (PDT) is reported to be high in several studies 2, 3, 4, 5, 6.
• A study published in 2021 found that the overall clearance rate at 3-year follow-up was 96.1% for superficial BCCs treated with methyl aminolevulinate-mediated photodynamic therapy (MAL-PDT) 4.
• Another study published in 2011 reported a complete response rate of 82% for superficial BCCs treated with MAL-PDT 3.
• A review of randomized controlled trials published in 2024 found that PDT was less effective than surgery but had better reported cosmetic outcomes 2.
• The use of daylight PDT for superficial BCC is not explicitly mentioned in the provided studies, but the available evidence suggests that PDT is a safe and effective treatment option for superficial BCC.

Comparison of Cure Rates

• The cure rates for superficial BCC with PDT are generally high, ranging from 82% to 96.1% in the provided studies 3, 4.
• The study published in 2021 found that the cure rate for superficial BCC with MAL-PDT was 96.1% at 3-year follow-up, which is comparable to the cure rate reported in the study published in 2011 (82%) 3, 4.
• The review published in 2024 found that PDT was less effective than surgery, but had better reported cosmetic outcomes 2.

Factors Affecting Cure Rate

• The type of BCC (superficial or nodular) is a significant factor in determining the cure rate with PDT 3.
• The location of the lesion (trunk or limbs) may also affect the cure rate, with lesions on the trunk showing better response to PDT 3.
• The thickness of the tumor and the presence of ulceration may also impact the cure rate with PDT 3.