Study: RCM for Monitoring AKs Treated with ALA-PDT

Actinic keratosis (AK) occurs frequently in sun-exposed skin and more investigation is still needed in diagnosis and treatment of the skin condition. A recent study aimed to examine AKs with reflective confocal microscopy (RCM) as an in vivo monitoring and evaluating before and after 5-aminolevulinic acid photodynamic therapy (ALA-PDT).

In total, 32 patients with facial AK lesions were selected and examined with RCM then biopsied at the same site. RCM was used to observe AK lesions before the first ALA-PDT treatment, after the first treatment, after 4 treatments, and at a 1- and 6-month follow-up. A retrospective analysis of RCM images was performed.

All 32 AK cases showed initial RCM microscopic features including disorderly arranged epidermal cells, atypical keratinocytes, and blurry border between the epidermis and dermis. There were 4 patients who discontinued participation in the trail.

After treatments, 24 AKs demonstrated regular arrangement of epidermal cells, absent atypical keratinocytes, and clear border between epidermis and dermis, while 4 cases improved little. At the 1- and 6-month follow-up, 23 cases remained relapse-free while 1 case developed recurrent symptoms. Effective rate of 4 ALA-PDT treatments for AK was 100%; recurrence and cure rates were 4.2% and 82.1%, respectively, the article continued.

“ALA-PDT is effective to treat AK, while RCM can be recommended for in vivo evaluating and monitoring the effect of ALA-PDT on AK,” the authors wrote.

Reference:

Tan L, Zhang Y, Huang J, et al. In vivo reflectance confocal microscopy for monitoring actinic keratosis treated with 5-aminolevulinic acid photodynamic therapy. Skin Research and Technology. 2021;27(5):871-879. doi:10.1111/srt.13036