Abstract
Photodynamic therapy (PDT) with methyl-aminolevulinate (MAL) is an approved non-invasive treatment option for actinic keratoses (AKs). In vivo reflectance confocal microscopy (RCM) is a non-invasive tool for real-time imaging of epidermis and superficial dermis in vivo that has been previously reported to facilitate the in vivo evaluation of skin lesions, including AKs. The aim of this study was to investigate the use of in vivo RCM in evaluating AKs response to MAL-PDT. For this reason a total of 10 biopsy-proven AKs were treated by MAL-PDT, according to standard PDT protocol for AKs. RCM investigation was performed before and after PDT and RCM-guided punch biopsies was taken at 3 months in all patients for histopathologic examination. At 3 months follow-up, complete clinical response was observed by clinical examination in 9 out of 10 lesions and a partial clinical response in 1 lesion. In vivo RCM detected two residual AKs in subclinical form, missed by clinical examination. Histological analysis confirmed these results. In vivo RCM may be a new alternative tool for the non-invasive diagnosis of AKs and evaluation of AKs response to non-invasive treatments, as MAL-PDT, improving the ability of dermatologists to diagnose AKs even in subclinical stage.
Highlights
Actinic keratoses (AKs) are one of the more common premalignant cutaneous lesions, clinically present as erythematous, hyperkeratotic macules, papules or plaques typically occurring in chronically sun-exposed skin, such as the face, lower lip, scalp, ears, neck, forearms, hands and lower legs
AKs and squamous cell carcinomas (SCCs) exist in field cancerization on a continuum from subclinical keratinocyte dysplasia to invasive SCC, so AK have been histologically classified as cutaneous SCC in situ [2]
reflectance confocal microscopy (RCM) was an excellent tool to monitor the response in both cases [12]. In agreement with these results the present study suggests that RCM was able to identify AKs, even in a very early sub-clinical stage, and to assess the response of AKs treated with methyl aminolevulinate (MAL)-photodynamic therapy (PDT)
Summary
AKs can occur as a single lesion or, more frequently, as multiple, appearing on a chronically photodamaged area, or field cancerization. The concept of field cancerization describes the presence of genetic abnormalities in a tissue chronically exposed to a carcinogen (e.g., ultraviolet radiations light exposure) [1]. These abnormalities are responsible for the presence of multilocular clinical and sub-clinical (nonvisible, nonpalpable) cancerous lesions that explains the increased risks of multiple cancers in this area. AKs and squamous cell carcinomas (SCCs) exist in field cancerization on a continuum from subclinical keratinocyte dysplasia to invasive SCC, so AK have been histologically classified as cutaneous SCC in situ [2]. Topical photodynamic therapy (PDT) with methyl aminolevulinate (MAL) has proven to be effective, non-invasive and with better cosmetic results for AKs [3]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
