Background: Actinic keratoses (AK) represent cutaneous carcinoma in situ and have previously been evaluated by reflectance confocal microscopy (RCM). Treatment of AK with imiquimod (IMIQ) 5% cream has been shown to 'highlight' subclinical lesions.
Objective: The aim of this study was to test the applicability of RCM for noninvasive monitoring of actinic field cancerization and detection of subclinical AK.
Subjects and methods: AK and surrounding skin sites with no apparent AK of 11 volunteers were selected for imaging and subsequently classified as 'clinical' and 'subclinical' AK. IMIQ was used 3 times weekly for 4 weeks.
Results: RCM was able to detect morphologic features of AK in both clinical and subclinical AK; features were more pronounced in clinical lesions. The immunomodulatory response induced by IMIQ was visualized by RCM.
Conclusion: Our findings indicate that RCM allows noninvasive monitoring of treatment response in vivo and permits early detection of subclinical AK, thus substantiating the incentive for therapy.
Copyright 2009 S. Karger AG, Basel.