Line-field confocal optical coherence tomography in melanocytic and non-melanocytic skin tumors

INTRODUCTION: Line-field confocal optical coherence tomography (LC-OCT) is a recently introduced, non-invasive skin imaging technique combining the technical advantages of reflectance confocal microscopy and conventional OCT in terms of isotropic resolution and in-tissue penetration. Several studies have been published so far about the use of LC-OCT in melanocytic and non-melanocytic skin tumors. The aim of this review was to summarize the currently available data on the use of LC-OCT for benign and malignant melanocytic and non-melanocytic skin tumors.EVIDENCE ACQUISITION: We searched scientific databases for any literature published up to 30th April 2023 and concerning the use of LC-OCT for melanocytic and non-melanocytic skin tumors. Identified papers were evaluated, and relevant information was extracted.EVIDENCE SYNTHESIS: A total of 29 studies were found including original articles, short reports, and letters to the Editor: 6 applied to melanocytic skin tumors, 22 to non-melanocytic skin tumors and 1 to both. The use of LC-OCT increased the diagnostic accuracy for me-lanocytic and non-melanocytic skin lesions. The highest diagnostic performance was found for basal cell carcinoma (BCC), but significant improvements in the diagnostic accuracy were also detected for the differentiation of actinic keratosis (AK) from squamous cell carcinoma (SCC) and of melanoma from nevi. The LC-OCT features of other skin tumors were also described and successfully correlated with histo-pathology.CONCLUSIONS: LC-OCT proved to increase the diagnostic accuracy for melanocytic and non-melanocytic skin lesions, thanks to the combi-nation of high resolution/penetration, 3D reconstructions, and integrated dermoscopy. Although BCC seems the most suitable tumors for LC-OCT examination, the device is extremely performant for the differentiation of AK from SCC and the discrimination of melanoma from nevi as well. Additional studies on diagnostic performance and new investigations about the presurgical assessment of tumor margins with LC-OCT and its association with human and artificial intelligence algorithms are in progress.