The role of reflectance confocal microscopy in differentiating melanoma in situ from dysplastic nevi with severe atypia: A cross-sectional study

Publication Trends and Hot Topics in Dysplastic Nevus Research: A 30-Year Bibliometric Analysis

INTRODUCTION

Dysplastic nevi are pigmented lesions that exhibit clinical and histological features of both common nevi and melanoma. In recent years, there has been an increase in publications on dysplastic nevi. Bibliometric analysis is a method of evaluating trends in large number of publications and identifying popular topics.

OBJECTIVES

The objective of this study is to provide an overview of the landscape of publications related to dysplastic nevi, visualize trends and identify popular topics in the literature.

METHODS

Thomson Reuters' Web of Science database was searched with the following query in title, abstract or keywords: TS = ("dysplastic nevus" OR "clark nevus" OR "atypical nevus" OR "dysplastic nevi" OR "clark nevi" OR "atypical nevi"). Time span was set to 1992-2022. Document type was set to Article. Titles, authors, abstracts, institutions, countries, journals, references, and the citation information were recorded.

RESULTS

Although the number of publications has declined over time, the USA remains the leading contributor to published articles. Key clusters of frequently used keywords were identified. The Journal of the American Academy of Dermatology had the highest number of published titles. Country and journal analysis were supplemented by co-citation and co-cited reference cluster analysis. Burst analyses revealed authors like Kittler, Argenziano, and Gandini as significant contributors, with their works receiving strong citation bursts extending until the end of the study period.

CONCLUSIONS

This bibliometric analysis revealed trends and interest pockets in the literature pertaining to dysplastic nevi and melanoma. This study aids in understanding the current research landscape and highlights potential future directions in this field.

A Single-Institution Cohort Study With Nevi of Special Site: Recurrence, Progression to Melanoma, and Patterns of Management

ABSTRACT

Nevi of specialized sites (NOSS) occur on the scalp, ears, flexural, acral, and genital areas and display atypical clinical and histologic features. We assessed NOSS recurrence and progression to melanoma, management patterns, and associations between histologic features and treatment recommendations. We queried all histologic diagnoses of NOSS (n = 275) from 2012 to 2017 from a large U.S. academic medical center with reference dermatopathology laboratory and matched these to clinical records. A blinded panel of dermatopathologists re-evaluated lesions, catalogued histologic findings, and gave management recommendation. Associations with dermatopathologist decision and concordance between new and original recommendations were assessed. Of 117 cases with follow-up, 2 locally recurred (1.46%) and none eventuated in melanoma. Clinical features were not associated with original treatment recommendations. After histopathologic review, large melanocytes [odds ratio ratio (ORR) = 8.00, 95% CI, 1.35-47.4] and junctional mitotic figures (ORR = 65.0, 6.5-650) predicted excision recommendation. Likewise, accumulation of many (>9) high-risk features was associated with excision recommendation. Panel review changed treatment recommendation in 27% of cases. Fair concordance existed between original and panel recommendations (κ = 0.29, 0.15-0.44). The low rate of recurrence and lack of melanoma occurrence suggest that despite an atypical clinical and histopathologic appearance, these nevi have limited potential for malignant transformation. Histopathologic findings seem to be principal drivers behind the recommendation for excision in this analysis. Variability existed in treatment recommendations; the panel's consensus recommendation tended to downgrade treatment. This highlights the importance of further outcomes-based studies to identify true high-risk features and refine management guidelines.

Dysplastic nevus part I: Historical perspective, classification, and epidemiology

Since the late 1970s, the diagnosis and management of dysplastic nevi have been areas fraught with controversy in the fields of dermatology and dermatopathology. Diagnostic uncertainty and lack of standardized nomenclature continue to propagate confusion among clinicians, dermatopathologists, and patients. In part I of this CME review article, we summarize the historical context that gave rise to the debate surrounding dysplastic nevi and review key features for diagnosis, classification, and management, as well as epidemiology. We discuss essentials of clinical criteria, dermoscopic features, histopathologic features, and the diagnostic utility of total body photography and reflectance confocal microscopy in evaluating dysplastic nevi, with emphasis on information available since the last comprehensive review a decade ago.

Texture Analysis in Diagnosing Skin Pigmented Lesions in Normal and Polarized Light-A Preliminary Report

The differential diagnosis of benign nevi (BN), dysplastic nevi (DN), and melanomas (MM) represents a considerable clinical problem. These lesions are similar in clinical examination but have different prognoses and therapeutic management techniques. A texture analysis (TA) is a mathematical and statistical analysis of pixel patterns of a digital image. This study aims to demonstrate the relationship between the TA of digital images of pigmented lesions under polarized and non-polarized light and their histopathological diagnosis. Ninety pigmented lesions of 76 patients were included in this study. We obtained 166 regions of interest (ROI) images for MM, 166 for DN, and 166 for BN. The pictures were taken under polarized and non-polarized light. Selected image texture features (entropy and difference entropy and long-run emphasis) of ROIs were calculated. Those three equations were used to construct the texture index (TI) and bone index (BI). All of the presented features distinguish melanomas, benign and dysplastic lesions under polarized light very well. In non-polarized images, only the long-run emphasis moment and both indices effectively differentiated nevi from melanomas. TA is an objective method of assessing pigmented lesions and can be used in automatic diagnostic systems.

Line-Field Confocal Optical Coherence Tomography: A New Tool for the Differentiation between Nevi and Melanomas?

Until now, the clinical differentiation between a nevus and a melanoma is still challenging in some cases. Line-field confocal optical coherence tomography (LC-OCT) is a new tool with the aim to change that. The aim of the study was to evaluate LC-OCT for the discrimination between nevi and melanomas. A total of 84 melanocytic lesions were examined with LC-OCT and 36 were also imaged with RCM. The observers recorded the diagnoses, and the presence or absence of the 18 most common imaging parameters for melanocytic lesions, nevi, and melanomas in the LC-OCT images. Their confidence in diagnosis and the image quality of LC-OCT and RCM were evaluated. The most useful criteria, the sensitivity and specificity of LC-OCT vs. RCM vs. histology, to differentiate a (dysplastic) nevus from a melanoma were analyzed. Good image quality correlated with better diagnostic performance (Spearman correlation: 0.4). LC-OCT had a 93% sensitivity and 100% specificity compared to RCM (93% sensitivity, 95% specificity) for diagnosing a melanoma (vs. all types of nevi). No difference in performance between RCM and LC-OCT was observed (McNemar's p value = 1). Both devices falsely diagnosed dysplastic nevi as non-dysplastic (43% sensitivity for dysplastic nevus diagnosis). The most significant criteria for diagnosing a melanoma with LC-OCT were irregular honeycombed patterns (92% occurrence rate; 31.7 odds ratio (OR)), the presence of pagetoid spread (89% occurrence rate; 23.6 OR) and the absence of dermal nests (23% occurrence rate, 0.02 OR). In conclusion LC-OCT is useful for the discrimination between melanomas and nevi.

Line field confocal optical coherence tomography: An adjunctive tool in the diagnosis of autoimmune bullous diseases

Autoimmune bullous diseases (AIBDs) still represent a considerable a source of morbidity and mortality: early identification of a specific AIBD is often difficult due to overlapping clinical and/or laboratory features and time-consuming invasive laboratory tests. We aimed to investigate the potential role of a new imaging technology, line-field confocal optical coherence tomography (LC-OCT), in the non-invasive diagnosis of AIBDs. LC-OCT was performed at lesional, perilesional and contralateral healthy sites in 30 patients, before histology and direct immunofluorescence. LC-OCT examination was able to identify the level of split (subcorneal/suprabasal/subepidermal/sublamina densa), to provide detailed images of the bulla roof morphology and content (eg, erythrocytes/acantholytic cells/polymorphonucleates). Areas of intra/subepidermal detachment were also detected also at clinically normal perilesional skin sites. LC-OCT can support physicians, real time and at bed-site, in the differential diagnosis of various AIBDs and their mimickers. Moreover, it can be used for the identification of subclinical lesions and therapy tapering.

Dynamic dermoscopic and reflectance confocal microscopic changes of melanocytic lesions excised during follow up

BACKGROUND

Digital dermoscopy follow up (DDF) is useful in improving the recognition of melanoma, catching early changes over time, although benign nevi can also show changes. Reflectance confocal microscopy (RCM) improves accuracy in diagnosing melanoma and decreases the number of unnecessary resections.

OBJECTIVE

To evaluate dynamic dermoscopic and RCM changes during follow up of equivocal melanocytic lesions and assess the impact of adjunctive RCM to DDF for melanoma diagnosis.

METHODS

A retrospective, multicenter study of extrafacial atypical melanocytic lesions excised during follow up was performed. Morphologic changes were evaluated, comparing dermoscopy and RCM baseline and follow-up images.

RESULTS

One hundred thirty-seven atypical melanocytic lesions were studied, including 14 melanomas and 123 benign nevi. Significantly greater changes in DDF of atypical network, regression, atypical streaks, and asymmetrical growth as well as in dynamic RCM of atypical cells and dermal-epidermal junction disarray were noted in melanomas. With adjunctive dynamic RCM and major changes at DDF, sensitivity reached 100%, with 40.6% specificity.

LIMITATIONS

Selected series of difficult to recognize lesions, with both DDF and dynamic RCM images.

CONCLUSION

Adjunctive dynamic RCM improves early melanoma recognition sensitivity.

Spatially-Resolved Multiply-Excited Autofluorescence and Diffuse Reflectance Spectroscopy: SpectroLive Medical Device for Skin In Vivo Optical Biopsy

This contribution presents the development of an optical spectroscopy device, called SpectroLive, that allows spatially-resolved multiply-excited autofluorescence and diffuse reflectance measurements. Besides describing the device, this study aims at presenting the metrological and safety regulation validations performed towards its aimed application to skin carcinoma in vivo diagnosis. This device is made of six light sources and four spectrometers for detection of the back-scattered intensity spectra collected through an optical probe (made of several optical fibers) featuring four source-to-detector separations (from 400 to 1000 µm). In order to be allowed by the French authorities to be evaluated in clinics, the SpectroLive device was successfully checked for electromagnetic compatibility and electrical and photobiological safety. In order to process spectra, spectral correction and metrological calibration were implemented in the post-processing software. Finally, we characterized the device’s sensitivity to autofluorescence detection: excitation light irradiance at the optical probe tip in contact with skin surface ranges from 2 to 11 W/m², depending on the light source. Such irradiances combined to sensitive detectors allow the device to acquire a full spectroscopic sequence within 6 s which is a short enough duration to be compatible with optical-guided surgery. All these results about sensitivity and safety make the SpectroLive device mature enough to be evaluated through a clinical trial that aims at evaluating its diagnostic accuracy for skin carcinoma diagnosis.