Usefulness of in Vivo Reflectance Confocal Microscopy and Automated Videomosaics in the Treatment and Management of Skin Cancers PDF Download

Author: Oriol Yélamos i Pena
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Languages : en
Pages : 158

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Book Description
"Skin cancer is major health problem due to its increased incidence in the last decades. Standard treatment of skin cancer is still surgery, which can be challenging to perform since most skin cancers are located in visible areas such as the face. Hence, methods to improve skin cancer treatment and minimize scarring are crucial. In this sense, non-invasive imaging technologies can be of great help in determining the margins of skin cancers prior to their treatment, as well as they offer a great opportunity to monitor its treatment and detect early relapses. Reflectance confocal microscopy (RCM) is one of this non-invasive imaging technologies which has cellular resolution and has shown to have high diagnostic accuracy for different types of skin cancers such as keratinocyte carcinomas, melanomas or Paget disease. Currently two RCM microscopes are commercially available: 1) a wide-probe microscope which requires attaching a metal/plastic ring on the skin to obtain image mosaics up to 8 x 8 mm; 2) a handheld RCM (HRCM) microscope which allows free imaging along the skin with a field of view which ranges from 0.75 to 1 mm. HRCM has the advantage that permits imaging areas larger than 8 x 8 mm by navigating over the skin but lacks mosaicking capabilities in its native software, making orientation complicated. However, it is intuitive to think that HRCM is the ideal tool to predefine the margins of skin cancers and to monitor its responses to treatment due to its versatility, especially when the size of tumor is larger than 8 mm. The goal of the current thesis was to develop a computer algorithm to obtain static 2D mosaics obtained from dynamic videos obtained with HRCM, and to apply this technique to address some of the challenges that physicians encounter when managing skin cancers, such as defining the skin cancer margins prior to surgery (particularly important in some skin cancers such as lentigo maligna [LM] which have ill-defined margins), identifying residual tumor directly in the surgical wound, and identifying small foci of tumor in recurrent or persistent skin cancers which present in a patchy fashion such as extramammary Paget's disease (EMPD). The research for this thesis resulted in 5 publications summarized herein. The first publication describes the videomosaicking algorithm as well as clinical to showcase how this algorithm can be used not only in RCM but in other microscopic imaging systems. The second publication applies the videomosaicking algorithm to delineate the preoperative margins in a consecutive series of 23 LM/LM melanoma, showing that the HRCM with videomosaicking can correctly predict the surgical defect after staged excision with minimal variations. In the third publication, HRCM was used to identify persistence or recurrence of EMPD after different treatments. Here, the videomosaicking algorithm was used in some of the patients and showed that the diagnostic accuracy improved when videomosaics were added to the conventional HRCM examination. In the fourth and fifth publications HRCM and videomosaics were used to image directly in the surgical wound after treating keratinocyte carcinomas (after laser ablation in the 4th publication, and after Mohs surgery in the 5th publication), showing it is possible to identify residual tumor using HRCM and videomosaics directly inside the surgical wound.In summary, this thesis shows how videomosaics expand the usefulness of HRCM in skin cancer management and overcome its main challenges by expanding the field of view and obtaining architectural information which is crucial when evaluating microscopic images." -- TDX.