Accuracy of dermoscopic criteria for the differentiation between superficial basal cell carcinoma and Bowen's disease

Dermoscopy to differentiate clinically similar inflammatory and neoplastic skin lesions

INTRODUCTION

Over the few last decades, dermoscopy has become an invaluable and popular imaging technique that complements the diagnostic armamentarium of dermatologists, being employed for both tumors and inflammatory diseases. Whereas distinction between neoplastic and inflammatory lesions is often straightforward based on clinical data, there are some scenarios that may be troublesome, e.g., solitary inflammatory lesions or tumors superimposed to a widespread inflammatory condition that may share macroscopic morphological findings.

EVIDENCE ACQUISITION

We reviewed the literature to identify dermoscopic clues to support the differential diagnosis of clinically similar inflammatory and neoplastic skin lesions, also providing the histological background of such dermoscopic points of differentiation.

EVIDENCE SYNTHESIS

Dermoscopic differentiating features were identified for 12 relatively common challenging scenarios, including Bowen's disease and basal cell carcinoma vs. psoriasis and dermatitis, erythroplasia of Queyrat vs. inflammatory balanitis, mammary and extramammary Paget's disease vs. inflammatory mimickers, actinic keratoses vs. discoid lupus erythematosus, squamous cell carcinoma vs. hypertrophic lichen planus and lichen simplex chronicus, actinic cheilitis vs. inflammatory cheilitis, keratoacanthomas vs. prurigo nodularis, nodular lymphomas vs. pseudolymphomas and inflammatory mimickers, mycosis fungoides vs. parapsoriasis and inflammatory mimickers, angiosarcoma vs granuloma faciale, and Kaposi sarcoma vs pseudo-Kaposi.

CONCLUSIONS

Dermoscopy may be of aid in differentiating clinically similar inflammatory and neoplastic skin lesions.

Clinical, Dermoscopic and Histopathological Evaluation of Basal Cell Carcinoma

INTRODUCTION

Dermoscopy aids in identifying histopathological subtypes and the presence of clinically undetectable pigmentation in basal cell carcinoma (BCC).

OBJECTIVES

To investigate the dermoscopic features of BCC subtypes and better understand non-classical dermoscopic patterns.

METHODS

Clinical and histopathological findings were recorded by a dermatologist who was blinded to the dermoscopic images. Dermoscopic images were interpreted by two independent dermatologists blinded to the patients' clinical and histopathologic diagnosis. Agreement between the two evaluators and with histopathological findings was evaluated using Cohen's kappa coefficient analysis.

RESULTS

The study included a total of 96 BBC patients with 6 histopathologic variants: nodular (n=48, 50%), infiltrative (n=14, 14.6%), mixed (n=11, 11.5%), superficial (n=10, 10.4%), basosquamous (n=10, 10.4%), and micronodular (n=3, 3.1%). Clinical and dermoscopic diagnosis of pigmented BCC showed high agreement with histopathological diagnosis. The most common dermoscopic findings according to subtype were as follows: nodular BCC: shiny white-red structureless background (85.4%), white structureless areas (75%), and arborizing vessels (70.7%); infiltrative BCC: shiny white-red structureless background (92.9%), white structureless areas (78.6%), arborizing vessels (71.4%); mixed BCC: shiny white-red structureless background (72.7%), white structureless areas (54.4%), and short fine telangiectasias (54.4%); superficial BCC: shiny white-red structureless background (100%), short fine telangiectasias (70%); basosquamous BCC: shiny white-red structureless background (100%), white structureless areas (80%), keratin masses (80%); micronodular BCC: short fine telangiectasias (100%).

CONCLUSIONS

In this study, arborizing vessels were the most common classical dermoscopic feature of BCC, while shiny white-red structureless background and white structureless areas were the most frequent non-classical dermoscopic features.

Frequency of Publication of Dermoscopic Images in Inter-observer Studies: A Systematic Review

Research interest in dermoscopy is increasing, but the complete dermoscopic image sets used in inter-observer studies of skin tumours are not often shared in research publications. The aim of this systematic review was to analyse what proportion of images depicting skin tumours are published in studies investigating inter-observer variations in the assessment of dermoscopic features and/or patterns. Embase, MEDLINE and Scopus databases were screened for eligible studies published from inception to 2 July 2020. For included studies the proportion of lesion images presented in the papers and/or supplements was extracted. A total of 61 studies (53 original studies and 8 shorter reports (i.e. research letters or concise reports)). published in the period 1997 to 2020 were included. These studies combined included 14,124 skin tumours, of which 373 (3%) images were published. This systematic review highlights that the vast majority of images included in dermoscopy research are not published. Data sharing should be a requirement for future studies, and must be enabled and standardized by the dermatology research community and editorial offices.

A Comparative Study of Pigmented and Non-pigmented Basal Cell Carcinoma in Reflectance Confocal Microscopy

BACKGROUND/AIM

Basal cell carcinoma (BCC) is a common skin cancer, especially in the elderly population. The probability of BCC development increases past the age of 55. Dermoscopy and reflectance confocal microscopy (RCM) are two modern tools useful in the diagnosis of BCC.

PATIENTS AND METHODS

This is a retrospective study conducted on a group of 21 patients with a confirmed diagnosis of BCC. All patients were examined by dermoscopy and RCM. Dermoscopic images were taken using a videodermoscope. RCM was performed in three layers: epidermal, dermoepidermal junction (DEJ), and superficial dermal layer. In each layer, a few RCM criteria of basal cell carcinoma diagnosis were taken into consideration.

RESULTS

Dermoscopy of pigmented BCCs revealed blue globules of pigment (p<0.05), gray and blue ovoid nests, which were absent in the entire non-pigmented carcinomas group. In RCM, the epidermis showed no differences between pigmented and non-pigmented carcinomas, however, significant differences were observed at the DEJ. In pigmented BCCs, cordlike structures and plump atypical cells were observed (p<0.05), while in non-pigmented carcinomas, dark silhouettes were present (p<0.05).

CONCLUSION

To our knowledge, that is the first study comparing features between pigmented and non-pigmented BCC by RCM. Pigmented and non-pigmented BCCs presented different features in both dermoscopy and RCM. Furthermore, RCM revealed more discriminating features at the DEJ than dermoscopy, thus can be more efficient in the differential diagnosis of difficult BCC.

Dermoscopy of porokeratosis: results from a multicentre study of the International Dermoscopy Society

BACKGROUND

The diagnosis of porokeratosis can be challenging, and knowledge about its dermoscopic features is limited.

OBJECTIVES

To describe the dermoscopic features of porokeratosis of Mibelli and disseminated superficial actinic porokeratosis (DSAP) and the frequency of these features in a larger case series. The interobserver concordance was also assessed.

METHODS

In this retrospective cohort study, members of the International Dermoscopy Society contributed macroscopic and dermoscopic images of histopathologically verified cases of porokeratosis of Mibelli or DSAP. Three observers independently reviewed the collected images to identify the presence of predefined dermoscopic features. Following this, a consensus meeting was held to agree upon which dermoscopic features were present in each lesion.

RESULTS

In total, 78 clinical and dermoscopic images of porokeratoses were collected. The most common dermoscopic feature was keratin rim, which was present in 74 lesions (92.3%). The most common vascular structures were dotted or glomerular vessels which were present in almost half of the cases (48.7%). Other relatively frequent dermoscopic findings were as follows: non-peripheral scales (44.9%), grey-brown dots or pigmentation along the keratin rim (38.5%), and light-brown pigmentation within the keratin rim (33.3%). Shiny white structures and blood spots or erosions along the keratin rim were findings never before described in porokeratosis and were detected in 16.7% and 17.9% of the lesions, respectively. Dermoscopic findings in porokeratosis of Mibelli and DSAP were similar except for fewer blood spots or erosions along the keratin rim and more light-brown pigmentation within the keratin rim in DSAP. The interobserver concordance ranged from 0.44 (moderate) to 0.84 (almost perfect).

CONCLUSIONS

The dermoscopic hallmark of porokeratosis is the keratin rim, a finding also allowing for almost perfect interobserver agreement. Pigmentation or erosions along the keratin rim, vascular structures, as well as scales, pigmentation or shiny white structures within the keratin rim are additional dermoscopic clues.

Dermoscopic features of basal cell carcinoma in skin of color: A retrospective cross-sectional study from Puducherry, South India

BACKGROUND

Dermoscopy is useful in the diagnosis of basal cell carcinoma (BCC). However, most descriptions of the dermoscopic features of BCCs are in Caucasians (skin types I-III) and there is a paucity of data in dark-skinned Indian patients.

AIMS

The aim of this study was to describe the various dermoscopic features of BCC in dark-skinned patients from South India and correlate these with the histopathologic subtypes.

METHODS

A retrospective observational study of biopsy-proven cases of BCC was conducted at a tertiary care center in South India using nonpolarized contact dermoscopy.

RESULTS

Sixty BCCs in 35 patients predominantly of skin phototypes IV or V were studied. These included 32 nodular, 27 superficial and 1 infiltrative type of BCC. The most common dermoscopic features noted were maple leaf-like areas (61.7%), blue-white veils (53.4%), ulceration (48.4%) and short fine telangiectases (46.7%). Ulceration, blue-white veils and arborizing vessels were significantly associated with nodular BCCs, while maple leaf-like areas, red-white structureless areas, multiple small erosions and spoke wheel areas were noted with superficial BCCs.

LIMITATIONS

The limitations of this study include its retrospective nature, the use of only nonpolarized light for examination, the lack of other histopathological variants of BCC as well as the lack of a comparison group.

CONCLUSION

We report a dermoscopic study of BCC in dark-skinned patients from Puducherry, South India. The blue-white veil was observed in half of the patients and was significantly associated with nodular BCCs. The addition of the blue-white veil to the diagnostic criteria for pigmented BCC could improve the diagnostic accuracy of dermoscopy in Indian patients.

Dermoscopy as a Tool in Differentiating Cutaneous Squamous Cell Carcinoma From Its Variants

Background

Dermoscopic features of cutaneous squamous cell carcinoma (cSCC) have been widely studied, but their accuracy should be further investigated.

Objectives

This study assessed the diagnostic accuracy of a set of predetermined dermoscopic structures for 3 variants of cSCC, namely Bowen disease, keratoacanthoma and invasive cSCC.

Methods

Dermoscopic images of 56 histopathologically confirmed cSCC lesions (9 Bowen disease lesions, 7 keratoacanthomas, and 40 invasive cSCCs) were examined, and the diagnostic accuracy of dermoscopic structures was assessed. Discriminative ability of statistically significant positive predictors was determined using receiver operating characteristic (ROC) curves, and defined as an area under the ROC curve >0.700.

Results

Dermoscopic structures with statistical significance and discriminative ability were: for Bowen disease, clustered glomerular vessels and erosions; for keratoacanthoma, a central keratin plug; and for invasive cSCC, a mixed color of the background. Clustered and glomerular vessels had, for Bowen disease, perfect diagnostic accuracy, with: sensitivity of 88.9% for both features; specificity of 97.9% and 93.6%, respectively; positive predictive value (PPV) of 88.9% and 72.7%, respectively; and negative predictive value (NPV) of 97.8% for both. Erosions had, for BD, high specificity (87.2%) and NPV (91.1%), but low sensitivity (55.6%) and PPV (45.5%). A central keratin plug had, for keratoacanthoma, high specificity (87.8%) and NPV (93.5%), but low sensitivity (57.1%) and PPV (40%). A mixed background color had, for invasive cSCC, high specificity (81.3%) and PPV (89.7%), but low sensitivity (65%) and NPV (48.2%).

Conclusion

Dermoscopy accurately differentiates BD, through clustered glomerular vessels, from keratoacanthoma and invasive cSCC. Dermoscopic structures of keratoacanthoma and invasive cSCC overlap, and only histopathologic analysis differentiates them precisely.

Real-life data on basal cell carcinoma treatment: Insights on clinicians' therapeutic choices from an institutional hospital registry

Basal cell carcinoma (BCC) is the most common skin cancer in white skin individuals. The treatment of choice is surgical excision, but several other therapeutic choices are available and might also be efficient and cost-effective in selected cases of low-risk BCC or when surgery is complicate or contraindicated. The aim of the current study was to analyze the applied treatments for BCC in the real-life practice of a tertiary hospital, and investigate factors associated to the tumor and the patients that might influence the treatment selection of clinicians. Data on all BCCs treated from 1st January 2018 to 31st December 2019 were extracted. A total of 751 BCCs from 585 patients were included. The baseline characteristics of patients and tumors, the type of applied treatment and the histopathologic report when available were analyzed. Most tumors were located on the head/neck (64.2%). The most frequently applied treatment was surgical excision (580/751, 77.2%). In 22.8% of tumors a nonsurgical treatment was selected. The most frequently selected alternative treatments were, imiquimod, cryosurgery, their combination (immunocryosurgery), and vismodegib. A pretreatment diagnosis of superficial BCC was associated with a 12-fold increased probability of selecting a nonsurgical treatment except of vismodegib. Every added year of age increased the probability of selecting a nonsurgical treatment by 3-fold. Every added mm of diameter increased the possibility of vismodegib use by 4%. Surgery is the most frequently applied BCC treatment, but nonsurgical modalities do also have an essential role in real settings.

Dermatoscopic features of thin (≤2 mm Breslow thickness) vs. thick (>2 mm Breslow thickness) nodular melanoma and predictors of nodular melanoma versus nodular non-melanoma tumours: a multicentric collaborative study by the International Dermoscopy Society

BACKGROUND

Thin nodular melanoma (NM) often lacks conspicuous melanoma-specific dermatoscopic criteria and escapes clinical detection until it progresses to a thicker and more advanced tumour.

OBJECTIVE

To investigate the dermatoscopic morphology of thin (≤2 mm Breslow thickness) vs. thick (>2 mm) NM and to identify dermatoscopic predictors of its differential diagnosis from other nodular tumours.

METHODS

Retrospective, morphological case-control study, conducted on behalf of the International Dermoscopy Society. Dermatoscopic images of NM and other nodular tumours from 19 skin cancer centres worldwide were collected and analysed.

RESULTS

Overall, 254 tumours were collected (69 NM of Breslow thickness ≤2 mm, 96 NM >2 mm and 89 non-melanoma nodular lesions). Light brown coloration (50.7%) and irregular brown dots/globules (42.0%) were most frequently observed in ≤2 mm NMs. Multivariate analysis revealed that dotted vessels (3.4-fold), white shiny streaks (2.9-fold) and irregular blue structureless area (2.4-fold) were predictors for thinner NM compared to non-melanoma nodular tumours. Overall, irregular blue structureless area (3.4-fold), dotted vessels (4.6-fold) and serpentine vessels (1.9-fold) were predictors of all NM compared to non-melanoma nodular lesions.

LIMITATIONS

Absence of a centralized, consensus pathology review and cases selected form tertiary centres maybe not reflecting the broader community.

CONCLUSIONS

Our study sheds light into the dermatoscopic morphology of thin NM in comparison to thicker NM and could provide useful clues for its differential diagnosis from other non-melanoma nodular tumours.

Dermoscopic features of basal cell carcinoma and its subtypes: A systematic review

BACKGROUND

Multiple studies have reported on dermoscopic structures in basal cell carcinoma (BCC) and its subtypes, with varying results.

OBJECTIVE

To systematically review the prevalence of dermoscopic structures in BCC and its subtypes.

METHODS

Databases and reference lists were searched for relevant trials according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies were assessed for the relative proportion of BCC dermoscopic features. Random-effects models were used to estimate summary effect sizes.

RESULTS

Included were 31 studies consisting of 5950 BCCs. The most common dermoscopic features seen in BCC were arborizing vessels (59%), shiny white structures (49%), and large blue-grey ovoid nests (34%). Arborizing vessels, ulceration, and blue-grey ovoid nests and globules were most common in nodular BCC; short-fine telangiectasia, multiple small erosions, and leaf-like, spoke wheel and concentric structures in superficial BCC; porcelain white areas and arborizing vessels in morpheaform BCC; and arborizing vessels and ulceration in infiltrative BCC.

LIMITATIONS

Studies had significant heterogeneity. Studies reporting BCC histopathologic subtypes did not provide clinical data on pigmentation of lesions.

CONCLUSION

In addition to arborizing vessels, shiny white structures are a common feature of BCC. A constellation of dermoscopic features may aid in differentiating between BCC histopathologic subtypes.