Fluorescence demarcation of basal cell carcinoma controlled by histopathological mapping

Journal article, 2004

The demand for fast and effective tools for diagnosis of skin cancer is increasing due to the escalating incidence of skin cancer in recent years. Fluorescence imaging has gained rising interest for detection and delineation of basal cell carcinoma (BCC), which is the most common type of skin cancer. By applying δ-5-aminolaevulinic acid (ALA) protoporphyrin IX (Pp IX) is accumulated in the tumour; hence, the Pp IX can be used as a fluorescent marker for tumours. More information may be obtained by combining the ALA induced fluorescence with fluorescence without externally applied fluorophore, so called autofluorescence. In this work we present a method for demarcation of BCC, using a non-expensive multispectral imaging set up assisted by image warping for image alignment. To calibrate the method, histopathological mapping has been carried out by excising the tumours with Mohs micrographic surgery. The Z-images, combining information of autofluorescence and ALA induced fluorescence, showed good agreement with the histopathological mapping of BCCs located on the face in 5 out of 12 patients and partial agreement in 7 patients. Since the face is an area where demarcation of tumours usually is considered difficult, this result shows a potential for the method as a pre-operative guiding tool for this type of skin lesions.