Detecting Field Cancerization Using a Hyperspectral Imaging System

BackgroundField cancerization denotes subclinical abnormalities in a tissue chronically exposed to UV radiation. These abnormalities can be found surrounding the clinically visible actinic keratoses. ObjectivesThe aim of this study was to test the feasibility of a hyperspectral imaging system in the detection of multiple clinical and subclinical AKs for early treatment of the affected areas. Materials and MethodsAltogether 52 clinical AKs in 12 patients were included in this study. In six patients digital photos were taken of the naive AKs, and again after methylaminolevulinate(MAL)-fluorescence diagnosis which was used to teach HIS to find subclinical lesions. After 2-3 days when the MAL had vanished, the hyperspectral images were taken. Biopsies were taken from clinical AKs, healthy-looking skin and several suspected subclinical AKs. In the other six patients digital and hyperspectral images were taken of the naive AKs followed by one biopsy per patient. ResultsHIS detected all clinically visible 52 AKs and numerous subclinical lesions. The histopathology of the 33 biopsied lesions were concordant with the HIS results showing either AK (n=28) or photodamage (n=5). Of the 28 histopathologically confirmed AKs, 16 were subclinical. A specific diffuse reflectance spectrum of an AK and healthy skin was defined. ConclusionThe hyperspectral imaging system offers a new, non-invasive method for early detection of field cancerization. Lasers Surg. Med. 45:410-417, 2013. (c) 2013 Wiley Periodicals, Inc.