Dermoscopic Criteria Research Articles

Dermoscopy of inflamed seborrheic keratosis: A great mimic of malignancy

Clinical and dermoscopic recognition of seborrheic keratoses (SKs) is often straightforward, and biopsy might not be required. However, inflamed SKs (iSKs) can pose a diagnostic challenge. Dermoscopic features of iSKs have not yet been evaluated to date. To assess the diagnostic ability of a group of dermatologists to diagnose iSKs by dermoscopy. To evaluate the dermoscopic findings of a long series of inflamed seborrheic keratoses. Clinical and dermoscopic images of 100 difficult-to-diagnose skin tumours, including 29 iSKs, were presented to 33 clinicians (24 dermatologists and 9 dermatology residents), who were blinded to the diagnosis. The dermoscopic features of a series of 219 iSKs were retrospectively analysed. iSKs were correctly identified in a 37.6% of cases. Classic dermoscopic criteria were present in only 47% of iSKs. The most frequent dermoscopic feature in iSKs was the presence of vascularization (91.3%), but only a 44.5% showed predominance of hairpin vessels. A bluish hue was observed in 18.3% of lesions. Seven dermoscopic patterns were identified, based on the dermoscopic similarity to other tumours: seborrheic keratosis-like (28.8%); squamous cell carcinoma-like (25.6%); melanoma-like (17.8%); keratoacanthoma-like (6.8%); basal cell carcinoma-like (5.9%); verruca vulgaris-like (5.9%); nevus-like (2.3%). The diagnosis of iSKs can be challenging even with dermoscopy. They may behave as authentic mimics of other cutaneous tumours, including squamous cell carcinoma or melanoma. For this reason, histopathological examination should be mandatory in these cases.

Dermoscopic criteria of discoid lupus erythematosus: An observational cross-sectional study of 28 patients.

Discoid lupus erythematosus (DLE) affects mainly the head and neck and lesions heal with scaring. Early diagnosis of DLE is crucial; dermoscopy may enable early diagnosis and help to assess the prognosis of well-established lesions.To describe the dermoscopic features of DLE and to correlate them with the histological findings, site and duration of DLE.This study included 28 patients diagnosed as DLE based on clinical and histopathological examination. We examined the lesions clinically, dermoscopically and histopathologically. Evaluated dermoscopic variables were based on data in the available literature and on our observations.Whitish scales (89.3%), arborizing blood vessels (85.7%), follicular plugging (82.1%), and pigmentation (82.1%) were the commonest dermoscopic findings. Radial arrangement of arborizing blood vessel in between a radially arranged perifollicular whitish halo (starburst pattern) (39.3%) was noticed for the first time in this study. Rosettes (57.1%) were also seen. There was significant agreement between many dermoscopic and pathological findings with high sensitivity and specificity of many dermoscopic variants in the diagnosis of DLE. Follicular plugging, perifollicular whitish halo, starburst pattern, follicular red dots and rosettes were detected in early stages of the disease but structureless whitish areas and telangiectasia need more time to develop.We examined our patients at the time of presentation only without prospective monitoring and we had a relatively small sample size.Dermoscopy helps in the diagnosis of DLE at different body sites.

Dermoscopic criteria of discoid lupus erythematosus: An observational cross-sectional study of 28 patients.

Discoid lupus erythematosus (DLE) affects mainly the head and neck and lesions heal with scaring. Early diagnosis of DLE is crucial; dermoscopy may enable early diagnosis and help to assess the prognosis of well-established lesions. To describe the dermoscopic features of DLE and to correlate them with the histological findings, site and duration of DLE. This study included 28 patients diagnosed as DLE based on clinical and histopathological examination. We examined the lesions clinically, dermoscopically and histopathologically. Evaluated dermoscopic variables were based on data in the available literature and on our observations. Whitish scales (89.3%), arborizing blood vessels (85.7%), follicular plugging (82.1%), and pigmentation (82.1%) were the commonest dermoscopic findings. Radial arrangement of arborizing blood vessel in between a radially arranged perifollicular whitish halo (starburst pattern) (39.3%) was noticed for the first time in this study. Rosettes (57.1%) were also seen. There was significant agreement between many dermoscopic and pathological findings with high sensitivity and specificity of many dermoscopic variants in the diagnosis of DLE. Follicular plugging, perifollicular whitish halo, starburst pattern, follicular red dots and rosettes were detected in early stages of the disease but structureless whitish areas and telangiectasia need more time to develop. We examined our patients at the time of presentation only without prospective monitoring and we had a relatively small sample size. Dermoscopy helps in the diagnosis of DLE at different body sites.

Spitz Nevus with Features of Clark Nevus, So-Called SPARK Nevus: Case Series Presentation with Emphasis on Cytological and Histological Features.

Background: SPARK nevus represents a little-known and characterized entity, with few case series available in the literature. Methods and results: we present a case series of 12 patients (6 F and 6 M) between January 2005 and December 2020 and conduct a review of the current literature. Ten articles were selected on the basis of the adopted inclusion criteria and the PRISMA guidelines. Conclusions: The definition of histopathological and dermoscopic criteria are important to allow for an agreement to be reached among dermopathologists, and for the development of a consensus on higher case studies. To our knowledge, there are not many case series in the literature, and ours is part of the attempt to increase the knowledge of an entity that remains little-known and characterized.

'Rainbow pattern': a dermoscopic sign of invasive melanoma.

The 'rainbow pattern' was initially described as a highly specific dermoscopic feature of Kaposi sarcoma. Since then, it has been reported in many benign and malignant cutaneous tumours, including a few malignant melanomas (MMs). To determine the frequency and presentation of this dermoscopic pattern in primary cutaneous MMs in comparison to other cutaneous tumours. The presence of a rainbow pattern was evaluated in a sample of 1100 dermoscopic images of different melanocytic and nonmelanocytic cutaneous neoplasms. The rainbow pattern was observed in 23 of 245 (9.4%) MM and 44 of 855 (5.1%) non-MM neoplasms. MMs presenting this feature were generally thicker: 82.6% > 1 mm and 43.0% > 2 mm. Compared with non-MMs, rainbow pattern in MMs was more commonly focal (82.7% vs. 36.4% nonfocal, P = 0.001) and associated with > 2 dermoscopic structures associated with MM (100% vs. 9% with fewer, P = 0.001). The rainbow pattern is a dermoscopic sign that can occasionally be observed in invasive MMs. In MMs, this feature is usually associated with other dermoscopic criteria of MM and located in a focal and eccentric area, as opposed to a diffuse and isolated presentation in non-MM neoplasms.

Basal cell carcinoma thickness evaluated by high-frequency ultrasounds and correlation with dermoscopic features.

Background Basal cell carcinoma (BCC) is the most common skin cancer and it can be easily treated by surgery or by various other physical modalities and topical chemotherapy. For metastatic, locally advanced BCC and for cancers that cannot be removed by surgery, sistemic drugs known as hedgehog pathway blocker are used. High-frequency ultrasound (HFUS) is a non- invasive technique used in diagnosis of some skin cancers. It has proven potentially useful for BCC management. In this study we used high frequency ultrasounds to evaluate BCCs' thickness and the correlation with dermoscopic features. Methods We examined 86 basal cell carcinomas with dermoscopy and with high frequency ultrasound. The main patterns identified by ultrasound were linear, ellipsoid and non-specific or undefined. Patients were divided by sex and age. The BCCs were grouped by anatomic location. Finally we recorded specific dermoscopic features of BCCs noting their presence/absence in lesions overall and in each of four quadrants. Then the lesions were excised and histological examination was made with definition of tumor thickness (in mm). Results In our study two main echographic patterns were described: linear, associated with superficial BCC, and ellipsoid, found primarily in nodular variants. However, a small percentage of lesions have otherwise non-specific patterns. We observed a significant correlation between echographic tumor thickness and histotype. We observed high concordance between histological tumor thickness and ultrasounds. Also dermoscopic criteria as large branching and blue ovoid nests were significantly associated with heightened histologic and echographic assessments of tumor thickness. Conclusions In our study we have confirmed the utility of ultrasound in the diagnosis of BCCs and for the first time we have correlated ultrasounds' patterns with dermoscopy and tumor thickness.

Dermoscopic Criteria, Histopathological Correlates and Genetic Findings of Thin Melanoma on Non-Volar Skin.

Dermoscopy is a non-invasive, in vivo technique that allows the visualization of subsurface skin structures in the epidermis, at the dermoepidermal junction, and in the upper dermis. Dermoscopy brought a new dimension in evaluating melanocytic skin neoplasms (MSN) also representing a link between clinical and pathologic examination of any MSN. However, histopathology remains the gold standard in diagnosing MSN. Dermoscopic–pathologic correlation enhances the level of quality of MSN diagnosis and increases the level of confidence of pathologists. Melanoma is one of the most genetically predisposed among all cancers in humans. The genetic landscape of melanoma has been described in the last years but is still a field in continuous evolution. Melanoma genetic markers play a role not only in melanoma susceptibility, initiation, and progression but also in prognosis and therapeutic decisions. Several studies described the dermoscopic specific criteria and predictors for melanoma and their histopathologic correlates, but only a few studies investigated the correlation among dermoscopy, pathology, and genetic of MSN. The aim of this work is to review the published data about dermoscopic features of melanoma, their histopathological correlates with regards also to genetic alterations. Particularly, this review will focus on low-CSD (cumulative sun damage) melanoma or superficial spreading melanoma, high-CSD melanoma, and nevus-associated melanoma.

Skin markings to differentiate benign from malignant lesions: A prospective observational study

Skin markings to differentiate benign from malignant lesions: A prospective observational study

International Dermoscopy Society criteria for non-neoplastic dermatoses (general dermatology): validation for skin of color through a Delphi expert consensus.

The International Dermoscopy Society (IDS) recently released a set of five basic dermoscopic parameters (vessels, scales, follicular findings, "other structures," and specific clues) encompassing a total of 31 subitems to standardize the use of dermoscopy in non-neoplastic dermatoses, yet they have been developed taking into account Caucasian/Asian skin, with consequent possible limitations if used in dark skin. To validate the abovementioned criteria for the use in dark-skinned patients (phototypes IV-VI) through an expert consensus. The two-round Delphi method was adopted, with an iterative process consisting of two rounds of email questionnaires. Potential panelists were recruited via e-mail from all over the world based on their expertise on dermoscopy of non-neoplastic dermatoses in skin of color. Twenty-two panelists took part in the validation process. All of the five originally proposed parameters and subitems reached agreement during the first round, aside from "follicular red dots." Additionally, during round 1, five new subitems were proposed (perifollicular scales distribution, follicular openings obliteration, broken hairs, eccrine pigmentation, and eccrine ostia obliteration), along with the possibility to change the denomination of parameter 3 (from "follicular findings" to "follicular/eccrine findings") and split it into two subparameters ("follicular findings" and "eccrine findings"). All such proposals reached agreement during the second round and therefore were included in the final list, for a total of 37 items. Although nearly all the dermoscopic criteria originally proposed by the IDS are applicable even to darker phototypes, several additional variables need to be assessed.

Prevalence of Dermoscopic signs in Egyptian psoriatic patients with different skin phototypes and different plaque locations

Dermoscopy is a non-invasive technique that has been recently utilized for the diagnosis and management of many skin disorders. It also provides information about inflammatory skin diseases e.g. psoriasis, lupus, and so on. Psoriasis is a papulosquamous disease with variable distribution, morphology, severity and course, affecting about 1.5% of the population. In this study 218 cases of classic psoriasis were examined clinically and by dermoscopy. Dermoscopic signs found in psoriasis were bushy capillaries (dotted vessels), erythema and scales. Bushy capillaries presented in 99.5% of all cases, erythema presented also in 99.5% and scales presented in 92.7%. We found that, type and site of psoriasis have little or no effect on erythema but have significant effect on scales especially flexural psoriasis due to humidity, and skin phototype has no or little effect on dermoscopic finding in psoriasis as there is no significant effect of skin color on visibility of the bushy capillaries, erythema or scales. In conclusion, the well-known dermoscopic criteria of psoriasis, namely bushy capillaries, erythema and scaling are seen in dark skin as well as in those in light skin, in lesions of different locations, with the frequency of white scales varying among different body sites.

Clinical-dermoscopic similarities between atypical nevi and early stage melanoma.

Atypical (Clark) nevi are benign tumors that may be considered precursors of melanoma. Many studies acknowledge a linear progression from typical to atypical nevi that eventually transform into melanoma. It is often challenging to differentiate a Clark nevus from melanoma, especially in its early stages, due to their clinical, dermoscopic, and histological resemblance. Dermoscopy is a powerful tool in early melanoma diagnosis, but it is a subjective method of examination. Therefore, the use of dermoscopic algorithms and checklists can overcome this issue. In the case of a difficult diagnosis, since both dermoscopy and histopathological exam are subjective methods of examination, modern molecular biology techniques can be used to distinguish between benign and malignant tumors. This study aimed to test the accuracy of specific clinical and dermoscopic criteria in order to distinguish between benign and malignant tumors, with a secondary objective to provide an overview of the clinical and dermoscopic features of atypical nevi and melanoma. In the present study, dermoscopic algorithms did not necessarily help distinguish benign and malignant tumors but demonstrated that nevi and melanoma have similar characteristics.

Dermoscopic Predictors of Benignity and Malignancy in Equivocal Lesions Predominated by Blue Color

Background: Blue color in dermoscopy can be seen in a wide range of benign and malignant lesions, melanocytic or not. Some blue-colored dermoscopic criteria have been associated with specific tumors, such as blue-white veil with melanoma and homogeneous blue with blue nevi. However, when blue color occupies a large part of the lesion’s surface, the dermoscopic assessment might be particularly challenging. Objective: To identify dermoscopic predictors associated with benignity and malignancy in tumors characterized by a predominant dermoscopic presence of blue color. Methods: We retrospectively screened our institutional database for tumors exhibiting blue color in at least 50% of their surface with available histopathologic diagnosis. Lesions with blue color covering less than 50% of their extent and lesions not histopathologically assessed were excluded. The dermoscopic images were evaluated for the presence of predefined criteria, including the characteristics of the blue color, coexisting colors, and the vascular structures. Results: Of 91 included tumors, 53 were benign (35 blue nevi, 10 angiomas, and 8 seborrheic keratoses) and 38 malignant (12 melanomas and 26 basal cell carcinomas). Our analysis revealed 3 potent dermoscopic predictors of benignity: extension of blue color in more than 75% of the surface, diffuse distribution of blue color, and absence of vessels, posing a 2.3-fold, 5.6-fold, and 6.7-fold increased probability of benignity, respectively. In contrast, asymmetric distribution of blue color, blue clods, coexistence of gray color and linear vessels were significantly predictive of malignancy, posing a 8.9-fold, 2.8-fold, 13.5-fold, and 10.4-fold increased probability, respectively. Conclusion: In predominantly blue tumors, the probability of malignancy is high when blue color is seen in clods or is asymmetrically distributed and when gray color or linear vessels coexist. In contrast, a diffuse distribution of blue color, its expansion in more than 75% of the surface, and the absence of vessels are highly suggestive of a benign tumor.

IFN-α and TNF-α serum levels and their association with disease severity in Egyptian children and adults with alopecia areata.

Alopecia areata (AA) is an autoimmune skin disease characterized by abnormal levels of several cytokines, such as interferon alpha (IFN-α) and tumor necrosis factor-alpha (TNF-α), which are T-helper type 1 cytokines that have important roles in the pathogenesis of AA. The aim of our study was to correlate circulating IFN-α and TNF-α levels with disease severity, activity, and clinical type in patients with AA and to evaluate the relationship between the two cytokines. We investigated serum IFN-α and TNF-α levels in 72 patients with AA (35 children and 35 adults) and 75 healthy control individuals (34 children and 41 adults) using the enzyme-linked immunosorbent assay (ELISA) technique. We evaluated AA severity using the Severity of Alopecia Tool (SALT) and determined the activity based on dermoscopic criteria of disease activity. Serum IFN-α and TNF-α concentrations were significantly higher in the patients than in the controls. There was a significant positive correlation between serum IFN-α and TNF-α levels in all patients with alopecia areata, as well as between serum TNF-α levels and disease severity in all patients and in children. Our results support the association between IFN-α and TNF-α levels and AA and suggest that TNF-α might be related to disease severity.

Clinical and Dermoscopic Factors for the Identification of Aggressive Histologic Subtypes of Basal Cell Carcinoma.

BackgroundInfiltrative basal cell carcinoma (BCC) has a higher risk for post-surgical recurrence as compared to the most common low-aggressive superficial and nodular BCC. Independent diagnostic criteria for infiltrative BCC diagnosis have not been still defined. Improving the pre-surgical recognition of infiltrative BCC might significantly reduce the risk of incomplete excision and recurrence.ObjectiveThe aim of this study is to define clinical and dermoscopic criteria that can differentiate infiltrative BCC from the most common low-aggressive superficial and nodular BCC.MethodsClinical and dermoscopic images of infiltrative, superficial, and nodular BCC were retrospectively retrieved from our database and jointly evaluated by two experienced dermoscopists, blinded for the histologic subtype. Pairwise comparisons between the three histologic subtypes were performed and multivariable logistic regression models were constructed in order to define clinical and dermoscopic factors independently associated with each subtype. To validate our findings, two experienced dermoscopists not previously involved in the study were asked to evaluate clinical and dermoscopic images from an external dataset, guessing the proper BCC subtype between infiltrative, nodular and superficial, before and after being provided with the study results.ResultA total of 481 histopathologically proven BCCs (51.4% nodular, 33.9% superficial, and 14.8% infiltrative) were included. We found that infiltrative BCC mostly appeared on the head and neck as an amelanotic hypopigmented plaque or papule, displaying ulceration on dermoscopic examination, along with arborizing and fine superficial telangiectasia. Shiny white structures were also frequently observed. Multivariate regression analysis allowed us to define a clinical-dermoscopic profile of infiltrative BCC.ConclusionsWe defined the clinical-dermoscopic profile of infiltrative BCC, allowing to differentiate this variant from superficial and nodular BCC. This will improve pre-surgical recognition of infiltrative forms, reducing the risk for post-surgical recurrence.

Dermoscopic evaluation of superficial spreading melanoma

BackgroundDermoscopy increases the sensitivity of the diagnosis of melanoma, leading to its early identification and increasing the chances of cure. ObjectiveTo describe the clinical and dermoscopic characteristics of superficial spreading melanomas, and to detect the differences between in situ and invasive 1-mm thick melanomas. MethodsThis was a cross-sectional study in which dermoscopic images of 58 melanomas, grouped according to their thickness, were evaluated. Results24 in situ melanomas were evaluated, 28 invasive melanomas with Breslow ≤ 1 mm (0.50 ± 0.22 mm) and six with Breslow > 1 mm (2.35 ± 2.02 mm). In situ melanomas were smaller than invasive melanomas. The most commonly found dermoscopic criteria were asymmetry (84.5%), three or more colors (81.0%), and atypical network (79.3%). A non-specific pattern was more common in in situ melanomas (p = 0.028) and atypical network in invasive melanomas with Breslow 1 mm presented inverted network (p = 0.018). Study limitationsThe sample was selected by convenience, since it was necessary to have a preoperative photo of the tumor, which may have led to the loss of clinically less significant lesions, as well as those highly suggestive of melanoma. ConclusionsMelanomas in early stages showed a more frequent nonspecific pattern and atypical network, while invasive melanomas showed a multicomponent pattern, three or more colors, and an inverted network.

A Study of Clinical, Dermoscopic and Histopathological Correlation in Follicular Keratotic Diseases: Preliminary Observations in 30 Cases.

Context:Follicular keratotic disorder is an abnormal keratinization affecting the follicular orifices and clinically characterized by hyperkeratotic follicular papules affecting various sites. Dermoscopy is a non-invasive diagnostic tool and differentiates closely resembling diseases as well as possibly prevents need for an invasive biopsy.Aim:This study was aimed to find the correlation between clinical, dermoscopic and histopathological findings in follicular keratotic diseases and to establish the dermoscopic criteria in the diagnosis of primary follicular keratotic diseases.Materials and Methods:This was a hospital-based prospective cross-sectional study of 30 consecutive patients clinically diagnosed with follicular keratotic diseases, irrespective of age and duration of the disease.Results:The study consisted of 30 patients with a mean age of 19.57 ± 9.69 years. The most common primary follicular keratotic disease observed was phrynoderma and secondary follicular keratotic disease was follicular lichen planus (lichen planopilaris). The predominant dermoscopic finding among all the follicular keratotic diseases was perifollicular scaling 29 (96.7%) followed by keratotic plug 28 (93.3%). The most common histopathological feature was dilated follicular infundibulum 22 (73.3%) followed by follicular plug 15 (50%) and dermal perivascular infiltration 22 (73.3%). The clinical and dermoscopic features showed a significant statistical association with the histopathological findings.Conclusion:Dermoscopy is a simple, non-invasive diagnostic tool that helps in differentiating and diagnosing the closely resembling follicular keratotic diseases.

Dermoscopic characterization of guttate psoriasis, pityriasis rosea, and pityriasis lichenoides chronica in dark skin phototypes: An observational study.

Dermoscopy as a diagnostic tool is attaining impetus in inflammatory dermatoses with the cumulative description of characteristic findings in most dermatoses obviating at times the need of biopsy. In this retrospective observational study, 20 histopathology confirmed cases each of pityriasis rosea (PR), guttate psoriasis (GP), and pityriasis lichenoides chronica (PLC) seen over a period of 3 years were included. Dermoscopy images were extracted from photography archives for evaluation and three lesions from each patient (60 lesions each) were analyzed. Comparison of dermoscopy characters was done among PR, GP, and PLC in pairs using chi-square test and a P-value of less than .05 was considered significant. Most common background color in PR (86.7%) and PLC (96.7%) was yellow to yellow-orange and in GP was dull red to pink (70%). Vessels were visualized in all lesions of GP and most characteristic pattern was regular (93.3%), dotted vessels (95%). In PR 63.3% lesions had dotted vessels mostly in a patchy distribution (56.7%). Most prominent scale color in PR was yellow-white (88.3%) and in GP was white-gray (80%). In PLC varying colors were seen, most prominent being brown (53.3%). Characteristic findings seen only in PLC were hypopigmented areas (13.3%), brown dots and globules (53.3%) and orange-yellow structureless areas (61.7%) GP, PR, and PLC reveal specific dermoscopic findings that can help in differentiating them. Further, the known dermoscopic criteria for GP, PR, and PLC also apply for dark skin phototypes.

Basal cell carcinoma thickness evaluated by high-frequency ultrasounds and correlation with dermoscopic features.

Basal cell carcinoma (BCC) is the most common skin cancer, and it can be easily treated by surgery or by various other physical modalities and topical chemotherapy. For metastatic, locally advanced BCC and for cancers that cannot be removed by surgery, systemic drugs known as hedgehog pathway blocker are used. High-frequency ultrasound (HFUS) is a non- invasive technique used in diagnosis of some skin cancers. It has proven potentially useful for BCC management. In this study we used high frequency ultrasounds to evaluate BCCs' thickness and the correlation with dermoscopic features. We examined 86 basal cell carcinomas with dermoscopy and with high-frequency ultrasound. The main patterns identified by ultrasound were linear, ellipsoid and non-specific or undefined. Patients were divided by sex and age. The BCCs were grouped by anatomic location. Finally, we recorded specific dermoscopic features of BCCs noting their presence/absence in lesions overall and in each of four quadrants. Then the lesions were excised, and histological examination was made with definition of tumor thickness (in mm). In our study, two main echographic patterns were described: linear, associated with superficial BCC, and ellipsoid, found primarily in nodular variants. However, a small percentage of lesions have otherwise non-specific patterns. We observed a significant correlation between echographic tumor thickness and histotype. We observed high concordance between histological tumor thickness and ultrasounds. Also, dermoscopic criteria as large branching and blue ovoid nests were significantly associated with heightened histologic and echographic assessments of tumor thickness. Our study confirmed the utility of ultrasound in the diagnosis of BCCs and for the first time we have correlated ultrasounds' patterns with dermoscopy and tumor thickness.

Dermoscopic Findings in the Presurgical Evaluation of Basal Cell Carcinoma. A Prospective Study.

Surgery is the best treatment for basal cell carcinoma (BCC); however, incomplete excisions are possible. Assessment of the accurateness of dermoscopy and clinical evaluation in the detection of borders of BCC and description of dermoscopic findings in clinically healthy tissue surrounding BCC. Eighty-eight lesions with clinical dermoscopic diagnosis of BCC were examined clinically and dermoscopically, to delineate the correct site of surgical incision, demarcating the respective margins with colred dermographic pencils. Specific dermoscopic features were searched in the skin adjacent to the demarcated clinical margin. In 29 of 88 lesions, clinical and dermoscopic margins of the tumor coincided. In the remaining 59 (67%), 10 (16.9%) presented, in the lesion area identified under dermoscopy, classical criteria for BCC and 57 (96.6%) nonclassical criteria. Differences between clinical and dermoscopic margins were significantly more frequent in superficial BCCs (p = .006). The frequency was not significantly different (p = .85) in relation to body sites. Dermoscopy improves the identification of margins for surgical excision in BCC. The observation of nontraditional dermoscopic criteria of BCC, mainly pink-white areas and short telangiectasias in the area between clinically and dermoscopically detected margins, helps to define the actual tumoral margins and to achieve a really radical excision.

Dermoscopic patterns of intradermal naevi.

Intradermal naevi represent a benign histopathological variant of common melanocytic naevi. Studies describing dermoscopic criteria of dermal naevi are very limited. To identify dermoscopic features of dermal naevi in order to facilitate differential diagnosis from malignant lesions. A 15-year retrospective study was performed to evaluate the dermoscopic characteristics of 202 dermal naevi, histopathologically diagnosed through the analysis of digital dermoscopic images performed with polarised light dermoscopy. For each lesion, vascular pattern, pigment pattern and other dermoscopic clues were evaluated. 147 Unna naevi and 55 Miescher naevi were included in the study. Brown pigment (37.1%) was the pigment pattern most frequently observed in both Unna and Miescher naevi, followed by cobblestone pattern (30.6%) in Unna naevi and white areas (23.6%) and dotted/globule pattern (20%) in Miescher naevi. As regards the vascular patterns, the polymorphic one was the most frequently observed (34.6%). The combination between comma-shaped and arborising vessels was the most common among all naevi. Our study describes the dermoscopic features of dermal naevi that may help to differentiate them from malignant lesions such as basal cell carcinoma, amelanotic melanoma and Spitz naevi.