Reflectance Confocal Microscopy Examination Research Articles

Basosquamous carcinoma: Comprehensive epidemiological, clinical, dermoscopic, and confocal features from a single center institution.

Basosquamous carcinoma (BSC) is a rare and aggressive nonmelanoma skin cancer (NMSC) that exhibits features of both BCC and squamous cell carcinoma (SCC). The gold standard for diagnosis is histopathological examination. BSC is often challenging to diagnose and manage due to its mixed histological features and potential for aggressive behavior AIM: To identify specific features aiding clinicians in differentiating BSCs using non-invasive diagnostic techniques. We conducted a retrospective descriptive, monocentric study of the epidemiological clinical, dermoscopic, and reflectance confocal microscopy (RCM) features of histopathologically proven BSCs diagnosed between 2010 and 2023. A total of 192 cases were selected. The study population consisted of 17 men (60.9%). Total 95.8% of patients at the time of diagnosis were≥50 years. BSC occurred in the head and neck area in 124 cases (63.1%) of which 65 (33.9%) were in the H-zone. For 47.4% of patients, BSC presented as a macule with undefined clinical margins (43.3%). Dermoscopic images were available for 98 cases: the most common parameter was the presence of whitish structureless areas (59 [60.2%]), keratin masses (58 [59.2%]), superficial scales, and ulceration or blood crusts (49 [50%] both). Vessels pattern analysis revealed hairpin vessels (exclusively) and linear irregular vessels as the most frequent (55 [56.1%] both). RCM examination was performed in 21 cases which revealed specific SCC features such as solar elastosis (19 [90.5%]), atypical honeycomb pattern (17 [89%]), proliferation of atypical keratinocytes (16 [80%]) combined with BCC' ones as bright tumor islands (12 [57.8%]), and cleft-like dark spaces (11 [53.4%]). Our study reflects the largest cohort of BSCs from a single institution. We described an incidence rate of 4.7%, higher than reported in the Literature, with the involvement of patients≥50years in almost 96% of cases and an overall male predominance. At clinical examination, BSC was described as a hyperkeratotic macule with undefined clinical margins with one or more dermoscopic SCC' features, whereas the presence of typical BCC aspects was observed in less than 10% of cases, differently from what was previously reported. At RCM analysis, BSCs presented with an atypical honeycomb pattern with proliferation of atypical keratinocytes, hyperkeratosis, and in nearly 55% of patients, bright tumor islands with cleft-like dark spaces. The distinctive dermoscopic patterns, along with the RCM features aid in the differentiation of BSCs from other NMSCs.

Analysis of the characteristics of reflectance confocal microscopy images of xanthogranuloma and xanthoma.

Both xanthogranuloma and xanthoma clinically manifest as yellowish skin lesions. Historically, the gold standard for diagnosis was skin histopathological examination. Currently, the advent of reflectance confocal microscopy (RCM) offers additional diagnostic support for these diseases by revealing their microscopic features, thereby enhancing the theoretical foundation for diagnosis. This study aimed to elucidate the distinctive characteristics of RCM images in xanthogranuloma and xanthoma, assess their diagnostic value, and investigate the relationship between RCM and histopathological features, ultimately boosting diagnostic accuracy. RCM and histopathological examinations were conducted on 13 patients with xanthogranuloma and 12 with xanthoma, recruited from our Dermatology Clinic between August 2022 and November 2023. The study involved analyzing RCM image features and correlating them with histopathological findings. The RCM images of 13 xanthogranuloma and 12 xanthoma cases showed similar features. Xanthogranuloma predominantly exhibited epidermal atrophy and thinning in 6 cases (46.15%). Additionally, in 69.23% of cases, scattered small mononuclear inflammatory cells were infiltrated in the superficial and middle dermis layers. Medium to high refractive cells, predominantly vacuolated and resembling foam, were observed in 61.54% of cases. All cases demonstrated high refractive cells with distinct target-shaped, disc-shaped, horseshoe-like, and flower-ring structures. Concordance rates with histopathological examinations were 69.23, 92.31, 92.31, and 100%, respectively. Regarding xanthoma, epidermal atrophy and thinning occurred in two cases (16.67%), and mononuclear inflammatory cell infiltration was observed in 25% of cases. High refractive cells with the previously mentioned shapes were present in 100% of cases, though only 16.67% displayed these characteristics exclusively. The concordance rates were 66.67, 91.67, 100, and 91.67%, respectively. RCM imaging of xanthogranuloma and xanthoma presents distinctive, highly consistent features with their histopathology, offering valuable insights for clinicians in diagnosing and differentiating these conditions.

In-depth study of Wood's lamp examination combined with reflective confocal laser scanning microscopy for the guidance of vitiligo staging and treatment.

Both Wood's lamp and reflective confidential laser scanning microcopy are helpful for the diagnosis and treatment of vitiligo. However, there is few research that contains large samples and consistent observations. To analyze the characteristics of Wood's lamp images and reflectance confocal microscopy (RCM) images of vitiligo lesions and to evaluate their significance in vitiligo staging. We analyzed the characteristics of RCM images, Wood's lamp images, the vitiligo disease activity (VIDA) score, and clinical features to guide vitiligo staging and treatment. The expert consensus based on the clinical features, VIDA score, Wood's lamp findings, and isomorphic response was consistent with the Wood's lamp findings (χ2 = 3.63, p > 0.05) and RCM findings (χ2 = 3.60, p > 0.05) in diagnosing vitiligo and assessing the disease stage. There was a correlation between the three lesion grades based on the Wood's lamp findings and the stage of vitiligo (p < 0.01). Lesions that appeared porcelain white under the Wood's lamp were in the slowly progressive stage; lesions that appeared gray-white or trichromatic under the Wood's lamp were in the rapidly progressive stage; lesions with clear borders under the Wood's lamp needed further analysis by RCM for the stage to be determined; lesions with blurred borders under the Wood's lamp were in the rapidly progressive stage; lesions that were visible under the naked eye and under the Wood's lamp were in the rapidly progressive stage. The study demonstrates a reliable correlation between the findings of RCM (a sophisticated expensive tool) and Wood's lamp examination (a simple, readily available, inexpensive tool) in the assessment of the disease activity of vitiligo lesions.

In Vivo View of a Reclining Demodex Mite in a Milia Cyst.

Demodex folliculorum and Demodex brevis are commonly present on facial skin and frequently noted via Reflectance Confocal Microscopy (RCM) examination. These mites inhabit follicles and are often seen in groups of two or more, although D. brevis is usually found as a solitary mite. When observed through RCM, they are typically present as refractile, round groupings seen on a transverse image plane inside the sebaceous opening, as they are vertically oriented, and their exoskeletons refract under near-infrared light. Inflammation may occur, leading to a variety of skin disorders; nonetheless, these mites are considered to be part of normal skin flora. a 59-year-old woman presented to our dermatology clinic for confocal imaging (Vivascope 3000, Caliber ID, Rochester, NY, USA) of a previously excised skin cancer for margin evaluation. She did not exhibit symptoms of rosacea or active inflammation of the skin. Incidentally, a solitary demodex mite was noted in a milia cyst nearby the scar. The mite appeared to be trapped in the keratin-filled cyst and was positioned horizontally to the image plane such that its entire body was captured in a coronal orientation as a stack. Demodex identification using RCM can provide clinical diagnostic value in the context of rosacea or inflammation; in our case, this solitary mite was thought to be part of the patient's normal skin flora. Demodex are practically ubiquitous on the facial skin of older patients and are frequently noted during RCM examination; however, the orientation of the mite referenced herein is uncommon, allowing for a unique view of its anatomy. The use of RCM to identify demodex may become more routine as access to technology grows.

Nevus Sebaceous of Jadassohn in Adults—Can Reflectance Confocal Microscopy Detect Malignant Transformation?

Nevus sebaceous of Jadassohn (NSJ) is a rare congenital lesion that affects the adnexal structures of the skin. It is typically located on the scalp and face of females and presents as a well-defined, slightly elevated, yellow lesion. It is also linked to a high risk of secondary tumors, which are more frequently benign than malignant. In vivo reflectance confocal microscopy (RCM) is a non-invasive imaging technique that provides a horizontal image of the skin with a resolution similar to histology. We report a case of basal cell carcinoma (BCC) developed in an NSJ with its dermoscopic, confocal, and histopathological features. A 49-year-old female presented with a well-circumscribed, 1 cm-diameter verrucous, yellowish lesion surrounded by a poorly defined, slightly erythematous, translucent plaque, located on the scalp in the temporoparietal region, which had been present since birth, grew at puberty, and changed its appearance in the last three years. Dermoscopy of the central lesion revealed yellow globules grouped into clusters, with peripheral linear and arborescent thin vessels, surrounded by several translucent nodular lesions with fine, arborizing vessels. RCM examination showed large, monomorphic cells with a hyperreflective periphery and a hyperreflective center located on the central lesion, corresponding to sebocytes, surrounded by multiple dark silhouettes lined with hyperreflective bands of thickened collagen, corresponding to tumor islands. The histopathological findings confirmed the diagnosis of BCC developed on an NJS. RCM can be a useful technique for the non-invasive examination and monitoring of these lesions, taking into account their transformation risk and preventing unnecessary excisions that might have a detrimental aesthetic impact on patients.

Reflectance confocal microscopy examinations of COVID-19 vaccination sites: A prospective observational study

Reflectance confocal microscopy (RCM) provides cellular-level insights into cutaneous pathology in vivo and is used to guide both diagnosis and management. The COVID-19 vaccine is the first messenger RNA vaccine in widespread use. Because a variety of cutaneous reactions associated with the COVID-19 vaccination have been reported,1 there may be value in identifying characteristic cellular features using RCM following vaccination. In this study, we used RCM to observe changes in the skin following COVID-19 vaccination.

The challenge of Diagnosing Common Dermatomycosis by Reflectance Confocal Microscopy

Background: Traditional detection of fungal infections of the skin relies on microscopy techniques or fungal culture. Currently, reflectance confocal microscopy (RCM) has been widely applied to assist the diagnosis of commondermatomycosis with advantages of non-invasiveness, celerity, real time, and repeatability. Materials and Methods: A total of 478 clinically suspected dermatomycosis patients were enrolled in this study including 148 cases of tinea manus and pedis, 188 cases of tinea corporis and cruris and 142 cases of pityriasis versicolor. RCM examination was performed to image the lesions. Aim: This study aimed to summarize the image characteristics of in vivo RCM examination on common dermatomycosis and retrospectively evaluate its accuracy as compared with microscopy results. Furthermore, we attempted to tackle the challenges of RCM diagnosis on common dermatomycosis. Results: Based on RCM images, 231 of 478 (48.3%) patients were detected with hyphae. Among all RCM confirmed cases, 58 out of 148 (39.2%) were tinea manus and pedis, 145 out of 188 (77.1%) were tinea corporis and cruris, and 28 out of 142 (19.7%) were pityriasis versicolor. The remaining patients (51.7%) could not be diagnosed by the dermatologist according to RCM. Hyphae structures were primarily identified during diagnoses of dermatomycosis by RCM. Conclusions: RCM is a novel optical imaging technique that confers high-resolution images of fungi. RCM has certain advantages in the diagnosis of tinea manus and pedis. RCM is not suitable for the diagnosis of pityriasis versicolor.

Melanocytic or Not? Dermoscopy and Reflectance Confocal Microscopy for Lesions Difficult to Diagnose: A Cross-Sectional Diagnostic Accuracy Study.

Different techniques for non-invasive skin examination and early diagnosis of skin lesions are available nowadays, being dermoscopy and reflectance confocal microscopy (RCM) the most diffused ones. Several studies supported the complementary use of dermoscopy and RCM that improves diagnostic accuracy when dealing with melanocytic lesions. To analyze RCM diagnostic accuracy in the differential diagnosis between melanocytic and non-melanocytic lesions. This is a cohort selected cross-sectional study conducted at the Dermatology Unit of the University of Campania L. Vanvitelli, Naples, Italy, from 2012 to 2020. We searched the image database for all excised lesions for which the clinical and dermatoscopic differential diagnosis was between melanocytic and non-melanocytic and for which an RCM examination was performed. Sensitivity, specificity, and diagnostic accuracy values were estimated. The study included 53 cases that were found to have disagreement between clinical, histological and RCM diagnosis, of which, in 31 cases the differential diagnosis was melanocytic vs non-melanocytic lesion. The RCM reached a specificity of 87% (95% CI: 0.73-1) and a sensitivity of 62.5% (95% CI: 0.29-0.96) in the present sample. Diagnostic accuracy was 80.6% (95% CI: 0.67-0.94). RCM has a high specificity in differentiating between difficult-to-diagnose melanocytic and non-melanocytic lesions.

Learning-based local quality assessment of reflectance confocal microscopy images for dermatology applications

Skin cancer is one of the most common types of cancer and its early diagnosis significantly reduces patient morbidity and mortality. Reflectance confocal microscopy (RCM) is a modern and non-invasive method of diagnosis that is becoming popular amongst clinical dermatologists. The frequent occurrence of artifacts in the images is one of the most challenging factors in making a diagnosis based on RCM. It impedes the diagnosis process for the dermatologist and makes its automation difficult. In this work, we employ artificial neural networks to propose a local quality assessment system. It allows for the detection of artifacts and non-informative component images both retrospectively or in real-time during the examination. In this research we address the quality assessment issue by proposing an artificial intelligence-based solution. 612 RCM mosaics were divided into small component images and manually classified in order to train the ResNeXt model in the quality verification context. A trained network was used to create an application that marks individual classes of the component images on the mosaic. We achieved the average classification precision of 0.98 both for the validation and test data sets. In addition, we present local quality assessment statistics of the 1540 cases of skin lesions to show which types of skin lesions most often present with artifacts in their RCM images. In this research we investigate the utility of the deep convolution neural networks for the local quality assessment of the RCM images. We propose an AI-based system that may be effectively used as real-time support for the dermatologist during a RCM examination and as a base for the automation of the diagnostic process.

Tips for difficult to diagnose hypomelanotic melanomas on reflectance confocal microscopy.

Amelanotic/hypomelanotic melanoma (AHM) represents a clinical diagnostic challenge. Dermoscopy improves AHM diagnosis thanks to visualization of little pigment and vascular pattern. Reflectance confocal microscopy (RCM) increases further the diagnostic accuracy of AHM but few and small studies have described in detail RCM features of AHM. We evaluated dermoscopic and RCM features of nine cases of difficult to diagnose hypomelanotic melanomas (HMs) to find clues for their diagnosis. The RCM score was suggestive of melanoma in all cases. The major criteria of nonedged papillae and/or cytological atypia at the dermo-epidermal junction were seen in all cases. Among the minor criteria, roundish pagetoid cells, including hyporeflective pagetoid cells, were found in four out of nine lesions. Dermoscopically, four out of nine HMs did not show prevalent suspicious criteria while revealing suspicious RCM features that were visible only after careful RCM examination by zooming mosaic images. RCM can improve HM diagnostic accuracy but only after extensive evaluation of images. Atypical cells were less reflective and the architectural irregularity was less visible than in pigmented melanoma and zooming was needed to identify both features.

Change in lentigo maligna score assessed by in vivo reflectance confocal microscopy after 1 month of imiquimod treatment for lentigo maligna management

Treatment of lentigo maligna (LM) is challenging because of the potential functional and esthetic surgical sequelae. Imiquimod has been proposed as a treatment for LM. Reflectance confocal microscopy (RCM) is a noninvasive method for the diagnosis of LM and margin assessment. To compare the overall LM score (LMS) assessed by RCM before and 1month after the start of imiquimod treatment compared to placebo and to define the immunohistochemical (IHC) profile of responders to imiquimod. A controlled randomized study was conducted. Forty patients underwent RCM examination with calculation of the LMS at baseline and after 1month of treatment. An IHC analysis of excised tissues was performed. The 1-month LMS was significantly lower in patients treated with imiquimod compared to those treated with placebo (P<.001). The criteria in the imiquimod-treated patients that demonstrated significant decrease were nonedged papillae; large, round pagetoid cells; atypical cells at the dermoepidermal junction; and follicular location of atypical cells. IHC analysis showed a higher level of interferon gamma in the resected specimens of patients responding to imiquimod (P=.04). Sample size was small. Assessing the LMS by RCM was useful to monitor LM response to imiquimod accurately.

Dermoscopy and reflectance confocal microscopy of balloon cell nevi: a series of 10 cases.

Balloon cell nevus (BCN) is a rare histopathological entity. It is usually represented by an asymptomatic brown smooth or polypoid lesion, but no clinical features allow differentiation from other melanocytic nevi. Moreover, dermoscopy and reflectance confocal microscopy (RCM) aspects of BCN have been described in a few single cases. This study aims to describe a wider BCN series with dermoscopic and RCM features to assess the most frequent patterns. Ten patients who underwent a BCN surgical excision with histological diagnosis were included in this study. Dermatoscopy and RCM were performed for each lesion, searching for the features described in literature. Each nevus presented as an asymptomatic, smooth brownish lesion. Regarding dermoscopy, four balloon cell nevi showed yellow globules, eight white globules, eight a light-brown network at the periphery, and eight a structureless central area; moreover, we found a hyperpigmented central blotch in four cases. RCM examination highlighted aggregates of dense nests at superficial dermis level in all BCNs, characterized by the presence of a dark nucleus surrounded by vacuolized cytoplasm. Moreover, multiple melanophages were seen at the dermal-epidermal junction in one case and superficial epidermal dendritic cells in one case. This series of 10 BCNs improves the dermoscopic and confocal microscopic knowledge of this rare entity. We also reported a new dermoscopic aspect represented by central hyperpigmented blotch. A correct identification of BCN with noninvasive techniques allows to avoid unnecessary surgical excision.

Review of Dermoscopy and Reflectance Confocal Microscopy Features of the Mucosal Melanoma.

Mucosal melanoma is a rare tumor with aggressive biological behavior and poor prognosis. Diagnosis is often performed at an advanced stage when the lesions become symptomatic. Although dermoscopy and reflectance confocal microscopy (RCM) are widely used techniques for the diagnosis of cutaneous tumors, their use for mucosal lesions is not well established, probably because the latter are rarer. The objective of this study was to evaluate current literature on these imaging techniques for mucosal melanoma. We searched in PubMed and Cochrane databases all studies up to October 2020 dealing with dermoscopy, RCM, and mucosal melanoma. We found that the most relevant dermoscopic features were structureless pattern and/or the presence of multiple colors. RCM examination mainly showed numerous basal hyper-reflective dendritic cells and loss of normal architecture of the papillae of the lamina propria. Although diagnostic algorithms have been proposed for both techniques, the limit of these methods is the absence of large studies and of standardized and shared diagnostic criteria.

In vivo reflectance confocal microscopy for evaluating seborrheic keratosis, verruca plana, syringoma and lichen nitidus.

In clinical, common facial papule dermatosis such as seborrheic keratosis (SK), verruca plana (VP), syringoma and lichen nitidus (LN) is often misdiagnosed. Summarizing in vivo reflectance confocal microscopy (RCM) features of the facial papule dermatosis is helpful in the diagnosis of ambiguous lesions. The purpose of this study was to evaluate the features of SK, VP, syringoma, and LN in RCM. We recruited 144 patients referred for unequivocal facial papule dermatosis including 60 patients with SK, 60 patients with VP, 10 patients with syringoma, and 14 patients with LN. The RCM images were evaluated at the epidermis, the dermoepidermal junction, and the dermis from both papule lesions and normal skin. In the epidermis, the cerebriform shape was the main RCM characteristic of SK and the "petal-like" structure was the main RCM characteristic of VP. In the dermoepidermal junction, the RCM features we found were as follows: For SK, the bright dermal papillary rings, the abnormal dermal papilla and the looped vessels were also observed at the abnormal dermal papilla. For VP, the bright dermal papillary rings and the point-like blood vessels were also observed at the round dermal papills. For LN, the round, enlarged, well-circumscribed dermal papillae and the enlarged dermal papillaes were heavily laden with individual highly refractive cells. In the dermis, RCM examination revealed brightly refractile teratogenous sweat tube, designing variably visible bright "moon" structures in all syringoma patients. Considering our results, RCM may be useful to non-invasively discriminate SK, VP, syringoma and LN in vivo.

Use of Reflectance Confocal Microscopy to Predict Treatment Efficacy in Café Au Lait Macules.

Multiple lasers have been used for the treatment of café au lait macules (CALMs) with various results. Objective tools to predict therapeutic efficacy of CALMs treatment is lacking. To determine whether reflectance confocal microscopy (RCM) characteristics correlate with CALMs response to laser treatment. All CAMLs underwent RCM examination of length and density of dermal papillae followed by 3 sessions of Q-switched alexandrite laser (QSAL). A visual analog scale was used to assess clinical treatment efficacy. Forty-three patients were included, 22 had CALMs with irregular borders and 21 with smooth borders. Café au lait macules with irregular border had shorter rete pegs and less papillae (p < .05) on RCM compared with smooth border CAMLs and responded better to QSAL treatment (2.32 vs 1.10). Reflectance confocal microscopy measurement of length and density of papillae were inversely correlated with treatment response. Reflectance confocal microscopy may be a useful tool to predict CALMs response to laser treatment.

Reflectance confocal microscopy characteristics of oral lichen planus: An analysis of 47 cases in a Chinese cohort.

Reflectance confocal microscopy (RCM) is a non-invasive tool that provides real-time microscopic images and relatively high-resolution tissue images. This technique provides a link between clinical examination and histopathology. RCM has been used to detect skin diseases and has also recently been applied to diseases of the oral mucosa. The present study aimed to explore the features of oral lichen planus (OLP) using RCM. A total of 47 patients with OLP exhibiting a reticular pattern, were included in the present study. The lesion sites and healthy adjacent sites were examined using in vivo RCM, with the lesion being histopathologically confirmed after RCM examination. The confocal images were reviewed, and the features were described. Sensitivity and specificity analysis of the RCM features was also performed. RCM examination presented parakeratosis, acanthosis and connective tissue papillae disappearance, with the presence of large melanocytes and roundish inflammatory cell infiltration, as well as dilated vessels in the lesion tissue. The sensitivity and specificity of OLP for dorsal tongue lesions were not as satisfactory as those on other sites. The results implied that RCM may be a promising technique to detect OLP non-invasively in vivo.

Features of classic lichen planopilaris and frontal fibrosing alopecia in reflectance confocal microscopy: A preliminary study.

Classic lichen planopilaris (LPP) and frontal fibrosing alopecia (FFA) are primary lymphocytic cicatricial alopecia. In patients with ambiguous clinical presentation, reflectance confocal microscopy (RCM) a new noninvasive skin imaging technique, could be a helpful diagnostic tool. The aim of our study was to describe the characteristic features of classic LPP and FFA using RCM. Ten patients with classic lichen planopilaris and two with frontal fibrosing alopecia were examined with RCM. Lichenoid inflammatory infiltrate around the hair follicle was observed in three cases of classic LPP and FFA (3/12; 25.0%). Extensive perifollicular fibrosis was seen in nine patients (9/12; 75.0%) with classic LPP and FFA. An increased number of white, ill-defined, coarse dermal fibers at the level of the superficial dermis were visible in seven cases (7/12; 58.3%). Moreover, dilated blood vessels were present in seven patients with classic LPP and FFA (7/12; 58.3%). Summing up, reflectance confocal microscopy allows to visualize major key diagnostic features of classic lichen planopilaris and frontal fibrosing alopecia in the real time. The value of RCM examination in scarring alopecia needs to be further evaluated, but it appears to be a useful adjuvant tool for the initial diagnosis of classic LPP and FFA.

Capillaroscopy and reflectance confocal microscopy characterization of refractory port-wine stains.

Port-wine stains (PWS) are frequently refractory to laser treatments. Although previous data highlight prognostic factors and biological events related to poor outcomes, no previous publications correlate their capillaroscopic and architectural features. The aim of the present study is to describe refractory port-wine stains performing capillaroscopy and reflectance confocal microscopy (RCM) to describe their morphological and microscopic aspects. This is a prospective cohort study. All the consecutive patients with PWS poor responsive to previous treatment were included. Clinical assessment, capillaroscopy, and reflectance confocal microscopy were performed. A total of 65 patients were included, 12 with a capillaroscopic Type II pattern patients and 53 with Type III. At RCM examination, PWS with a capillaroscopic Type III pattern showed deeper-located blood vessels (p < 0.001) with a higher diameter (p < 0.042) compared with Type II. At the dynamic evaluation, 3 RCM patterns can be distinguished: Subset A, characterized by linear vessels with reduced diameter; Subset B, formed by enlarged vessels; and Subset C, characterized by deep and large aneurysmatic dilatation connected to small vessels. We defined 3 RCM patterns of refractory PWS.

In Vivo Reflectance Confocal Microscopy-Diagnostic Criteria for Actinic Cheilitis and Squamous Cell Carcinoma of the Lip.

Actinic cheilitis (AC) is one of the most frequent pathologies to affect the lips. Studies show that the most commonplace oral malignancy, squamous cell carcinoma (SCC), often emerges from AC lesions. Invasive diagnostic techniques performed on the lips carry a high risk of complications, but reflectance confocal microscopy (RCM), a non-invasive skin imaging technique, may change the current diagnostic pathway. This retrospective study was aimed at consolidating the RCM diagnostic criteria for AC and lip SCC. The study was conducted in two tertiary care centers in Bucharest, Romania. We included adults with histopathologically confirmed AC and SCC who also underwent RCM examination. Of the twelve lesions included in the study, four were AC and eight were SCC. An atypical honeycomb pattern and the presence of target cells in the epidermis were RCM features associated with AC. SCC was typified by the presence of complete disruption of the epidermal architecture and dermal inflammatory infiltrates. The mean blood vessel diameter in SCC was 18.55 µm larger than that in AC (p = 0.006) and there was no significant difference (p = 0.64) in blood vessel density, as measured by RCM, between SCC and AC. These data confirm that RCM can be useful for the in vivo distinction between AC and lip SCC.

In Vivo Reflectance Confocal Microscopy in General Dermatology: How to Choose the Right Indication

Reflectance confocal microscopy (RCM) is a high-resolution, noninvasive imaging technique being increasingly used as an aid to diagnosis in the dermatology setting. RCM is applied in the diagnosis of both melanoma and nonmelanoma skin tumors, but also in the interpretation and management of inflammatory skin diseases. Two different devices with different designs for specific indications are available in the market: a static and a handheld probe. Several clinical presentations of the lesion could affect the examination, such as the presence of ulceration or hyperkeratosis; moreover, the anatomical site can drive the probe selection as well as the effective indication to RCM examination. In this review article, indications for the use of RCM are described in detail with a schematic approach for practical purposes.