Good day. So this will be a two-part series on how to utilize RCM in a busy clinical practice. In October of 2008, the VitaScope system was approved by the FDA for review by physicians to assist in forming a clinical judgment. But the question was, could this device really help in patient care? So I'd like to review some of our early experiences with the confocal microscope, which go way back to 2008, 2009. Our first case was a 55-year-old gentleman who was actually referred to me for Mohs surgery for a biopsy proving basal cell carcinoma of the forehead. Couldn't locate the site of the biopsy, which had been performed four weeks previously. And he felt it was in this area here. And with dermoscopy, what we saw were a few serpentine vessels, some scar-like area, and pink-white area. But if you looked at his entire forehead, it had similar features. So dermoscopy was not useful. With confocal microscopy, this is a mosaic of the granular spiny level. We see these shadows. These are dark silhouettes surrounded by thickened collagen. These are tumor islands. And these tumor islands are surrounded by this thickened collagen. In addition, we noted these spindle-shaped structures, dendritic cells. And here we can see on higher magnification the spindle-shaped cell, as well as these linear or canalicular vessels, which are running parallel to the horizontal plane. And this is classic for a basal cell carcinoma. A quick frozen demonstrated these tumor islands with clefting. And we went then on to do our Mohs surgery. And the key features for this particular case include the tumor islands at the level of the dermoepidermal junction, the fibrotic tumor stroma, the dilating torches, linear blood vessels, and these dendritic structures. Our second case is this 44-year-old woman with a history of melanoma. In situ, she had actually had this treated a year prior. And she came into our office with this faint brown mask while adjacent to the previous surgical site. This is what we saw with dermoscopy. We saw two different patterns. Pattern one were these early ridge formation, these we call fat fingers and mothy borders. And we saw a gray surrounding this one hair follicle. This was the features for this particular lesion. And we took a confocal picture. And what we saw with confocal were these early bulbous projections. And this is characteristic of a early lenigo slash seborrheic keratosis. And here you can see the increased amount of melanin in the keratinocytes lining the basal layer. Confocal picture two was this gray surrounding the hair follicle. And for this particular area, what we did was a stack. We're only looking at a half millimeter area of skin. And we're going down in a vertical direction. And as we go down this hair follicle, we start to see a few irregular-shaped cells, some cells that were bright. And as we go deeper, we see two different types of structures. We see these round, bright nucleated cells, which are pagetoid cells, and these dendritic cells. And this is characteristic, particularly when they're around the follicular openings of a melanoma in situ. And the teaching point of this is that pagetoid and dendritic cells extend down hair follicles are highly suggestive of melanoma on sun-damaged skin. Kesri was this gentleman who we saw for the first time with a history of non-melanocytic skin cancers and psoriasis. And he'd been treating this intermittently with topical steroid cream for quite a long time. Dermoscopically, it was nonspecific. All you really saw were some erosion, some fine-branching vessels in this pink-white area. It's nonspecific with dermoscopy. With confocal, however, at the mosaic of the granular spiny level, we saw some scale crust. In addition, we saw what's been called a disarranged pattern of the epidermis. We saw numerous pleomorphic cells. And we also saw that there were vessels traversing the papilla in a perpendicular fashion. These are all characteristic of squamous cell carcinoma and not psoriasis. And a quick frozen demonstrated numerous pleomorphic cells Bowen's disease. And the teaching point of this is that a atypical honeycomb or disarranged pattern is the most important feature for squamous cell carcinoma. In this particular case, it had many of the features that we look for for a squamous cell carcinoma in situ. These are some later cases. This was a gentleman who has a sea of benign characteristics on his back. But he had one lesion here, which on higher power, was this nine-millimeter scaly red-brown papule. And this is the way it looked. With dermoscopy, it had red and brown dots, some in a linear fashion. Vessels as linear red dots. And these are features we often see with a pigmented squamous cell carcinoma in situ. Now, a couple of years later, he develops this papule on his posterior leg. And dermoscopically, this has features of a melanoma with these dark structureless areas, focal vessels as dots, and globules are regularly distributed. And when biopsied, a thin, invasive melanoma. Two months later, post-treatment of the melanoma, we noted three dark papules on his cheek, upper lip, and right nose. And these are the three papules. Let's take a look at this one papule here. What we see here is a differential. Is this metastatic melanoma? He just, a couple months ago, had a melanoma in his posterior leg. Or is this a pigmented basal cell carcinoma? Not so easy. And I wasn't particularly confident. With dermoscopy, we saw these classic tumor islands. We also saw these bright, round cells, which are melanophages. We had some clefting, the tumor separating from the surrounding stroma. And when biopsied, a basal cell carcinoma. Metastatic melanomas have a distinct confocal pattern, different from this. Here we have an example of a metastatic melanoma. It's an isolated lesion. In dermoscopically, not so easy. There was a blue-brown globule, brown dots and focus. But confocally, a totally different pattern, consisting of these nests with pleomorphic cells, as well as large cells with dark centers, pagetoid cells. Our next case was this woman who had a flat, brown area with a fine scale within a vaccination scar. Now, this is what it looked like dermoscopically. I had no clue dermoscopically. All I saw was some well-circumscribed borders, numerous brown dots, but I couldn't put it into a pattern. In vaccination scars, basal cell carcinoma is the most commonly reported neoplasm. But squamous cell carcinoma, melanoma, and dermatofibrosarcoma protuberans have also been reported, as well as malignant fibrosis eositoma. What could RCM help? Well, on scanning magnification, it's an oblique section of the stratum corneum spinous granular level. We saw this honeycomb pattern visualized here. And over here, we had these spindle-shaped cells infiltrating the epidermis. And if we zoom in on this particular area, you could see numerous dendritic cells, but you could see they weren't aggregated together. They were kind of just dispersed. And at the DE junction, we had our major clue, which was a proliferation of round circles with a bright white rim. And these are the circles with the bright white rim. And this is pathognomonic for a pigmented squamous cell carcinoma in situ. And the spindle-shaped cells with the dendritic branches, these are actually Langerhans cells. And when biopsied, full-thickness atypia, a squamous cell carcinoma in situ. Now, this article was published. It involved these small brown circles, which was an important diagnostic clue for a pigmented squamous cell carcinoma in situ. And here you can see these circles with this brown peripheral rim. Some over here, we have brown oval structures in a linear arrangement. And when we do confocal, those circles with a brown peripheral rim are now circles with a white peripheral rim. And this is characteristic of pigmented squamous cell carcinoma in situ. You see the basilar hyperpigmentation with the numerous atypical keratinocytes throughout the epidermis. And we're looking at this point here when we see those circles with the white peripheral rim and with dermoscopy, the brown peripheral rim. Now, this was a gentleman referred by his primary care physician for this large nodular melanoma on complete exam. In addition, we noted he had two large brown patches of skin. Both melanoma in situ and dermoscopically had the classic features of an atypical network with regression structures and histologically confirmed. About five months later, the patient comes in with this changing pigmented lesion of the left upper chest. And here was his melanoma and here was that lesion. So that lesion actually was there before. And this is the dermoscopy features. Somewhat unusual features. And here's what we saw confocally. What we saw were these cords, which are characteristically seen with a seborrheic keratosis but in another area, there were tumor islands and these tumor islands had clefting. And this is an example of a collision tumor of a seborrheic keratosis and a basal cell carcinoma. And this article was published quite a few years back on 20 collision tumors, assessing using both dermoscopy and RCM and histologically confirmed. Dermoscopy was able to demonstrate 14 of the 20 neoplasms with the malignant component. In contrast, RCM diagnosed 19. And there was excellent concordance between RCM and histopathology with regard to the identification of a malignant component within a tumor. Case seven, this gentleman with this subtle pigmented lesion on his nose. Dermoscopically, it had an unusual and abnormal pattern characterized by some of these circles with a gray rim, as well as some regression structures. He really didn't want to have a biopsy, he didn't want a scar on his nose. On scanning magnification of the spiny granular superbasal level, we saw these bright cells infiltrating the epidermis. And if you look on higher magnification, you can see that there were numerous sheets of dendrites surrounding the follicular openings. And you can see these sheets of dendrites, we actually call this the head of Medusa, and this is characteristic and classic for melanoma in situ. An oblique section of the superbasal or DE junction demonstrated sheets of dendrites surrounding these follicular openings, but within the mesh, these are the retae, there were cells infiltrating the mesh. And this is characteristic of melanoma on sun-damaged skin, with many of the features which you can review on melanoma on sun-damaged skin, the RCM features. Histologically, we could see these atypical melanocytes at all levels of the epidermis, as well as around the adnexal structures. And the teaching point of this is that the two most important features, as I mentioned before, are the numerous spindle-shaped cells, the dendritic cells, and or round cells with a dark center. So here we have small lesion, isolated lesion on the nose, we always look for the isolated lesion. Here we can see some circles with this gray peripheral rim with RCM sheets of dendrites around the adnexal structures, melanoma. Another saddle lesion. Angulated lines, perhaps some early rhomboid formation. And again, look at all of these dendritic shells, these sheets of dendrites, again, surrounding the hair follicles and melanoma in situ. Case number eight was this gentleman with a history of melanoma and non-melanoma skin cancers, developed a pink-brown papule of the rhomboid cell. A papule of the right arm. Now, dermoscopically, this was our differential, a pigmented actinic keratosis, pigmented squamous cell carcinoma in situ, LPLK, and a melanoma in situ. And this is what we saw dermoscopically. Here we have a pigmented squamous cell, our question mark lesion, pigmented actinic keratosis with these multiple rosettes and melanoma. Would RCM be a benefit? The epidermis here has a typical honeycomb pattern with these numerous white oval structures and dark round depressed areas. These are the comedone-like openings. But there are no dendrites or pagetoid cells. And on higher magnification, now at the DE junction, we see a different pattern, which is characterized by these cord-like projections. And these cord-like projections, or bulbous projections, are characteristic of a seborrheic keratosis. There are some round, bright white cells. These bright white cells are stellate in pattern, which are characteristic of melanophagia. And this is a lichen planus-like keratosis. So this is what it looked like clinically. We gave this patient a course of topical steroid cream. This is three months follow-up. And at one year, it's completely gone. In this case, this is a woman who had this outlier lesion. And we can see here is this atypical network with light brown, dark brown. At the spiny granular level, super beta level, this is a typical cobblestone pattern. These are all pigmented keratinocytes. This is normal, normal pattern. Here we see these polymorphous papillae. And this overall pattern is very, very characteristic of a benign neoplasm, either a compound clark or congenitally of a superficial type. Here you can see the dermal nest. You can see some junctional nests coming off the retia as well. So in summary, does this device help in patient care? Yes, it does. Thank you for your attention.

reflectance confocal microscopy

skin conditions

basal cell carcinoma

melanoma

diagnosis