Investigate the Diagnostic Value and Possibilities of OCT in Non-Melanoma Skin Cancer.

Optimal management of skin malignancies relies on early and accurate diagnosis. The reference standard in skin cancer is biopsy and histopathological assessment from a clinical suspicious skin lesion. The clinical diagnosis of skin cancer has sensitivity ranging from 50% to 90 % and specificity around 70% to 80% depending on the population studied and the experience of the clinician. A rapid, non-invasive technique that could be used for characterization of skin lesions prior to biopsy would be valuable. In some patients with multiple, recurrent skin tumours the need for numerous biopsies in the same area is problematic, both cosmetically and diagnostically, as the cancer can be hidden under scar tissue. The biopsy has several weaknesses: The biopsy must be done exactly in the tumour, and it does not delineate the tumour borders. Biopsy from skin is in general easy, but there are problematic places such as the T-zone in the face, the eyelids and the ears. Notably these places are areas where most types of skin cancer exhibit aggressive, invasive growth and have a high recurrence rate. OCT is a novel, non-invasive optical imaging technology. It can provide cross-sectional tomographic images of tissue pathology in situ and in real time, without the need for excision and processing of specimens, as in conventional histopathology. OCT uses harmless, infrared light to create high-resolution images of tissue. OCT provides cross-sectional images of structures below the tissue surface in analogy to histopathology. Hence OCT can function as an "optical biopsy" providing images of tissue structure on the micron scale. For example, OCT could be used where standard excisional biopsy is hazardous or impossible, and OCT could reduce sampling errors associated with excisional biopsy.