Characteristic Dermoscopic Features Research Articles

Dermoscopic Diagnosis of a Non-Pigmented Skin Tumor: Eccrine Poroma

Dear Editor, Eccrine poroma stands as a benign adnexal neoplasm that originates from the acrosyringium. It typically emerges as solitary, flesh-colored, or erythematous papules, plaques, or nodules, primarily appearing in areas with sweat glands. As well as pigmented lesions, dermoscopy has proven to enhance the clinical diagnosis of numerous non-pigmented skin tumors, including eccrine poroma. Herein we present a case of eccrine poroma located on the dorsal aspect of the left foot, with characteristic dermoscopic features. A 60-year-old woman was admitted with an asymptomatic lesion on the dorsum of her left foot, which had manifested approximately four years before. Clinically, the lesion presented as a well-circumscribed, violaceous, 0.9x0.9 cm papule (Figure 1a). Dermoscopic examination revealed flower-like and leaf-like vascular patterns, white interlacing areas, glomerular vessels, and milky red globules (Figures 1c-d). The lesion was excised and histopathologic findings were consistent with eccrine poroma (Figure 1b). Eccrine poroma (EP) is an adnexal tumor originating in the intraepidermal part of the eccrine sweat gland duct. Dermoscopy and histopathology help to differentiate EP from pyogenic granuloma, seborrheic keratosis, verruca vulgaris, basal cell carcinoma, squamous cell carcinoma, and amelanotic melanoma. Well-defined dermoscopic features in EP are: White interlacing areas around vessels, milky-red globules, flower-like and leaf-like vascular patterns, glomerular vessels, hairpin vessels, yellow structureless areas, poorly visualized vessels, and well-circumscribed globular or lacuna-like structures separated by white to pink mesh bands [1-3]. Histologically, EP manifests as a well-contained tumor constituted of proliferative cuboidal or poroid cells, often extending from the basal epidermis into the dermal layer. Shave, electrosurgical destruction or simple excision may be the treatment of lesions, depending on the depth of the lesion. Kind Regards

Clinico-dermoscopic study of inflammatory dermatoses: a hospital based cross sectional study

Dermoscopy is a noninvasive, fast, and reliable diagnostic technique used to magnify and visualize structures on and beneath the skin surface which is difficult to observe by naked eyes, creating a link between macroscopic clinical dermatology and microscopic dermatopathology. The purpose of this study is to evaluate and compare the dermoscopic features of common inflammatory dermatological conditions of skin sharing similar clinical presentation according to the available literature data. All dermoscopic findings were studied using a handheld pocket dermoscopy (Dermlite DL1) with high magnification. Variables used for dermoscopic evaluation were divided into vascular and nonvascular features and specific clues. Descriptive analysis and Chi square test were used where appropriate and p < 0.05 was considered statistically significant. There were a total of 205 patients enrolled in the study. The most common clinical diagnosis was psoriasis seen in 42.0%, lichen planus in 13.0%, contact dermatitis in 12.0%, polymorphic light eruption 7.0%, seborrheic dermatitis 4.0%, discoid lupus erythematosus 5.0%, pityriasia Rosea 5.0%, urticaria 5.0% and others 7.0%. Dermoscopic vascular changes were seen as regular in 52.0% and irregular in 46.0%. The most common type of vessels observed were dotted in 70.0%, linear in 7.0%, and coiled in 2.0%. Non-vascular changes were seen in 61.0%. The commonest type of scales were whitish scales seen in 63.0%. Pigmentary changes were seen in 19.0%. The commonest type of vessels observed were dotted vessels (p value 0.000) in most inflammatory diseases. Features like wickham striae were characteristic of lichen planus (p value 0.000). The characteristic dermoscopic features of various inflammatory disorders with the help of a dermoscope is easy to perform in outpatient without any invasive method and also helpful in guiding management of the patients with follow-up.

Dermoscopic approach for differential diagnosing of autoimmune bullous disease: pemphigus vulgaris, pemphigus foliaceus, and IgA pemphigus.

Dermoscopy is a noninvasive technique for the evaluation of different pigments and microstructures of the epidermis, dermoepidermal junction, and papillary dermis that are not apparent to the naked eye, which therefore improves diagnostic accuracy. This study aims to describe the characteristic dermoscopic features of bullous diseases and analyze the characteristic dermoscopic features of bullous diseases of the skin and hair. A descriptive study was conducted to describe and analyze the characteristic dermoscopic features of bullous diseases in the Zagazig University Hospitals. This study enrolled 22 patients. Dermoscopy revealed yellow hemorrhagic crusts in all patients and white yellow structure with red halo in 90.9% of patients. Pemphigus vulgaris patients were identified by the presence of dermoscopic clues such as bluish deep discoloration, tubular scaling, black dots, hair casts, hair tufts, yellow dots with whitish halos (fried egg sign) and yellow follicular pustules that are not seen in pemphigus foliaceus and IgA pemphigus. Dermoscopy is an important tool that serves as a link between clinical and histopathological diagnoses, and it can easily be used in daily practice. Several suggestive dermoscopic features can help in the differential diagnosis of autoimmune bullous disease but only after making a provisional clinical diagnosis. Dermoscopy is a very useful tool in the differentiation of pemphigus subtypes.

Utility of Dermoscopy in the Diagnosis of Erythroderma: A Cross-Sectional Study

Background: It is difficult to diagnose the underlying cause of erythroderma on mere clinical presentation. The role of dermoscopy in diagnosing erythroderma secondary to various etiologies is evolving. Aim and Objectives: This study aimed to observe the dermoscopic features of erythroderma secondary to different cutaneous disorders and compare them with clinical features and histopathology. Materials and Methods: Twenty-nine consecutive patients of erythroderma were enrolled in the study. Dermoscopy was performed on every case using a Heine Delta II Dermatoscope with 10x magnification in polarized mode. A histopathological examination was conducted to confirm the diagnosis. Results: Eight patients were diagnosed with psoriasis, five with endogenous eczema, four with pityriasis rubra pilaris (PRP), three with pustular psoriasis, two with drug rash secondary to antitubercular therapy, two with dermatophytic infection, one patient each of atopic dermatitis, crusted scabies, pemphigus foliaceous, drug reaction with eosinophilia and systemic symptoms, and mycosis fungoides. Characteristic dermoscopic features were observed in erythroderma due to psoriasis, PRP, pustular psoriasis, endogenous eczema, scabies, and dermatophytosis. Differentiation of other disorders based on dermoscopy alone was difficult, and clinico-histopathological correlation was crucial to reach a diagnosis. Conclusion: Dermoscopic features of classical patterns of skin disorders are preserved even in the corresponding erythrodermic or unstable stage. Dermoscopic features of erythroderma secondary to psoriasis, pustular psoriasis, PRP, endogenous eczema, scabies, and dermatophytosis are clearly differentiating, whereas the dermoscopic features in other causes of erythroderma are overlapping. Thus, dermoscopy can be a good screening tool in the clinical assessment of erythroderma.

Dermoscopy aids in differentiating primary cutaneous amyloidosis and post-inflammatory hyperpigmentation: A clinico-dermoscopic-histopathaological study.

Primary cutaneous amyloidosis (PCA) and post-inflammatory hyperpigmentation (PIH) are common causes of cutaneous hyperpigmentation that are usually diagnosed clinically. However, their presentations are sometimes atypical, and their differentiation is difficult. Dermoscopy is a valuable diagnostic tool for pigmented diseases that might aid in their diagnosis. To describe the characteristic dermoscopic features of PCA and PIH together with histopathological correlation, and to differentiate between these conditions in a non-invasive way. Fifty-two patients with PCA (n=26) and PIH (n=26) were enrolled. A detailed history, skin examination, dermoscopic examination using handheld and video dermoscopy, and histopathological evaluation were performed. A statistically significant difference could be detected between PCA and PIH in terms of the duration of the disease (p=0.027), symmetry (p=0.044), rippling (p < 0.001), and back affection (p=0.048). On dermoscopic examination, central hubs were seen more in the PCA group (p < 0.001) with different patterns of peripheral pigmentation. Histopathologically, the number of melanophages per high-power field was significantly higher in the PCA group (p=0.013). The results of this study shed the light on the potential of dermoscopy as a non-invasive diagnostic tool in differentiating between doubtful cases of PCA and PIH.

Usefulness of Dermoscopy in Localized Scleroderma (LoS, Morphea) Diagnosis and Assessment-Monocentric Cross-Sectional Study.

Morphea, also known as localized scleroderma (LoS), is a chronic autoimmune disease of the connective tissue. The clinical picture of LoS distinguishes between active and inactive lesions. Sometimes the clinical findings are challenging to identify, and therefore, the need for additional methods is emphasized. Our study aimed to demonstrate the characteristic dermoscopic features in morphea skin lesions, focusing on demonstrating features in active and inactive lesions. In our patients (n = 31) with histopathologically proven LoS, we performed clinical evaluation of lesions (n = 162): active/inactive and according to both disease activity (modified localized scleroderma severity index, mLoSSI) and damage (localized scleroderma skin damage index, LoSDI) parameters. In addition, we took into account compression locations to determine whether skin trauma, a known etiopathogenetic factor in LoS, affects the dermoscopic pattern of the lesions. We performed a dermoscopy of the lesions, categorizing the images according to the severity within the observed field. We showed that within the active lesions (clinically and with high mLoSSI), white clouds and linear branching vessels had the highest severity. These features decreased within the observed field in inactive lesions and with high LoSDI. Brownish structureless areas were most intense in inactive lesions with high LoSDI. Erythematous areas, linear branching vessels, dotted vessels, and crystalline structures were statistically significant for pressure locations. We have shown dermoscopy is a valuable tool to assess the activity or inactivity of lesions, which translates into appropriate therapeutic decisions and the possibility of monitoring the patient during and after therapy for possible relapse.

Dermoscopy of cutaneous and palmar lichen nitidus

Lichen nitidus (LN) is a relatively uncommon chronic cutaneous lichenoid group of disease characterized by tiny quintessentially discrete hypopigmented to skin coloured papules commonly seen over dorsa of hands/forearms, lower abdomen, penis, and buttocks. The cutaneous manifestation of a disease on palms/soles varies from their presentation on body, which makes it difficult to diagnose at times. A 23-year-old healthy female presented with mildly itchy lesions on bilateral wrist, fingers, elbows, peri-umbilical area, and left palm since 6 months. On dermoscopy, we could appreciate the classical described findings of LN which were confirmed on histopathology. LN has a characteristic dermoscopic features, which come to rescue for diagnosis and also avoid a biopsy. We describe a rare presentation of palmar LN with two different morphologies along with classical cutaneous distribution of LN and their dermoscopy.

Dermoscopic Patterns in Juvenile Xanthogranuloma Based on the Histological Classification.

Background: Several dermoscopic features of juvenile xanthogranuloma (JXG) have been previously described in single cases or small case series and need to be further verified in a large sample.Objective: We aimed to investigate the dermoscopic patterns of JXG in a large case series and the correlations of these with clinical features of different histopathological subtypes of JXG.Methods: Patients who underwent dermoscopic evaluation and had a histopathological diagnosis of JXG were recruited. Histological findings, including stage and Ki67 proliferative index and the dermoscopic features of each lesion were recorded.Results: Forty-one patients with JXG were included. The male to female ratio was 1.28: 1 and the median age of onset was 11 months (range: 0–95 months). Fourteen lesions were histologically categorized in the early stage, 17 in the developed stage, and 10 in the late stage. The “setting sun” pattern was observed in 35 lesions (85.4%) and “clouds” of paler yellow areas in 26 lesions (63.4%). The frequency of the “setting sun” pattern was higher in the early and developed stages (30/31) than in the late stage (5/10) (P = 0.002), while that of “clouds” of paler yellow areas was not significantly different between each stage. Branched linear vessels were detected in the early (11/14) and developed stage (6/17), but not in the late stage. The mean Ki67 index of the lesions with linear vessels was 11.8% (range: 2–40%), which was higher than that of lesions without linear vessels (mean index: 5%, range: 1–30%) (P = 0.005). The pigment network and whitish areas were only detected in 6 and 5 lesions in the late stage, respectively. The whitish areas presented either as streak or stellate shape. The pigment network exhibited either in a centric or a peripheral pattern.Conclusions: The “setting sun” pattern is the characteristic dermoscopic features of JXG in the early and developed stages, while whitish areas and pigment network are the characteristic patterns in the late stage. Linear vessels present as branched patterns and mostly occur in the early stage with a high proliferative index, indicating rapid growth. The whitish areas and pigment network may present in various patterns. Dermoscopy is a useful adjunctive tool in the diagnosis and staging of JXG.

Cydnidae pigmentation − dermoscopic features

Pigmented spots on the skin are caused by burrowing bugs of family Cydnidae. These are commonly seen in monsoon, and the pigmentation is due to secretion by the insect. Here we report a case of Cydnidae pigmentation with characteristic dermoscopic features. Dermoscopic features included dark brown pigmentation over the dermatoglyphics with enhanced pigmentation around the sweat pores. The pigmentation which is seen commonly over the acral areas may be mistaken for lentigines or melanoma. Identifying the classical features on dermoscopy prevents the patient from undergoing unwanted investigations.

Characteristic Clinical and Dermoscopic Features of Nonvolar Poroma.

A poroma typically presents as a solitary, pink-to-red papule or nodule in acral volar areas. However, in nonvolar areas, this typical clinical feature (TCF) can be difficult to identify. We aimed to compare clinical and dermoscopic characteristics between nonvolar poroma (NVP) and volar (ie, typical) poroma (VP). We assessed the clinical and dermoscopic characteristics of 40 patients with poromas who were divided into the NVP and VP groups. Of the 40 patients, 20 (50.0%) were allocated to the NVP group and 20 (50.0%) to the VP group. Pigmented variants were more common in the NVP group than in the VP group (60.0% vs 5.0%). The TCF of poroma was observed less frequently in the NVP than the VP group (45.0% vs 85.0%). Approximately one-third (30.0%) of patients with NVP received an initial clinical diagnosis of skin cancer. Dermoscopic patterns associated with melanoma or basal cell carcinoma were more common in the NVP group than in the VP group (65% vs 30%). Skin cancer-associated clinicodermoscopic features were more frequently observed in patients with NVP, who simultaneously lost dermoscopic patterns associated to poromas and acquired those associated with skin cancer, than those with VP.

A descriptive observational study on clinical and dermoscopic features of benign melanocytic neoplasms.

Benign melanocytic neoplasms have nests of melanocytic cells and show characteristic dermoscopic features. Clinical and dermoscopic features have not been studied previously in the Indian population. To study the clinical, epidemiological and dermoscopic patterns of benign melanocytic neoplasms. This was a descriptive, observational, single centre study. In 107 patients with melanocytic neoplasms, 167 lesions were clinically examined and studied under the dermoscope and histopathological examination was done when indicated. The lesions were broadly divided as acquired and congenital. Five main dermoscopic patterns were seen-globular, homogenous, reticular, parallel and streaks. If there were two of these patterns in a particular lesion, it was termed 'mixed pattern'. The presence of three or more patterns was called 'multicomponent pattern'. Various other features were also observed. The majority of patients belonged to the third decade with a female preponderance. History of increased UV exposure and family history was significant in acquired nevi. The dermoscopic pattern progressed from predominantly reticular in junctional nevi to predominantly globular in compound nevi and lesser pigment in intradermal nevi, with more vascular structures. The congenital melanocytic nevi showed additional features of comedo- like lesions, milia- like cysts, perifollicular pigmentary changes and increased colour variation. Even though colour variation was observed in both acquired and congenital lesions, no signs of dysplasia were seen on histopathology. A larger sample size is required, with follow up of lesions. No parallel studies in brown skinned population were found for exact comparison. Benign melanocytic proliferations are often neglected in our country. This study will help in understanding the course, clinical features and dermoscopic patterns of various benign melanocytic neoplasms, and will be a step forward towards research in our population. To the best of our knowledge, this is the first study of its kind in India.

Utility of Dermoscopic Evaluation in Predicting Clinical Response to Diphencyprone in a Cohort of Patients with Alopecia Areata.

Background:Alopecia areata (AA) is a chronic and inflammatory disease of hair follicles, causing nonscarring alopecia. While the various types of treatment have been investigated, the definite cure for AA has not been established yet.Objectives:The objective of this study is to evaluate the clinical and dermoscopic features of patients with AA to identify the factors with prognostic values in diphenylcyclopropenone (DPCP) response rate.Methods:Eighty patients with AA were included, and baseline hair loss was calculated based on the severity alopecia tool (SALT) score. The characteristic dermoscopic features of AA were evaluated by two skilled dermatologists separately at baseline, 12 and 24 weeks afterward.Results:The mean SALT score in the 1st, 12th, and 24th week was 77 ± 24.7, 80 ± 27, and 71 ± 35.6, respectively, which were not significantly different over this time period (P = 0.085). SALT score correlated negatively with the short vellus hair/field (ρ = −0.361, P = 0.02), broken hair/field (ρ = −0.317, P = 0.044), and tapering hair/field (ρ = −0.388, P = 0.012) in the 1st week. Forty-one patients continued treatment courses over 24 weeks. Six patients had good response, 11 achieved partial response, and 24 had no hair regrowth. Statistically significant correlation was observed between treatment response and duration of disease (P = 0.04), frequency of relapses (P = 0.033), type of alopecia, and number of black dots (P = 0.028). The mean for all dermoscopic findings showed descending process during our three follow-up sessions which was statistically significant for black dot (P = 0.015) and broken hair (P = 0.006).Conclusion:The number of black dot per field initially was negatively correlated to DPCP therapy and the frequency of dermoscopic findings reduced during the treatment process.

The Role of Dermoscopy in Assessment of the Activity and Scarring Response in Discoid Lupus Erythematosus

Background:The diagnosis of Discoid Lupus Erythematosus (DLE) is usually made by clinical examination and by histopathology. Recently, dermoscopy has become an integral part in diagnoses of many inflammatory disorders and one of these is DLE.Aims:This research emphasizes the utility of dermoscopy in the assessing lesions of DLE from the point of activity of the disease.Patients and Methods:Thirty-one patients diagnosed with DLE were included in this study. The total number of examined lesions was 125 lesions. All of the lesions were assessed by dermoscopy at different stages of the activity of the diseases.Results:The dermoscopic features of DLE vary according to the stage of activity of the disease. There are characteristic dermoscopic features for the lesions of the scalp different from that of the body. In the active and early phase, the most common dermoscopic features were the presence of lesional and perilesional scales, follicular keratotic plugging, telangiectasia, arborized blood vessels, follicular red dots and perifollicular scales. In addition, there are less common dermoscopic features such as pigmentary changes, white rosettes and pinpoint white dots. For active scalp lesions, the follicular plugging and perifollicular scales were more prominent than that of the body DLE lesions. For inactive and late DLE lesions, the most significant dermoscopic changes were perifollicular whitish halos, variable patchy whitish hypopigmented areas, and the presence of white colored structureless areas.Conclusion:The present study provides new insights into the dermoscopic variability of DLE lesions at different levels of activity.

Assessment of a Predictive Scoring Model for Dermoscopy of Subungual Melanoma In Situ

Subungual melanoma in situ (SMIS) is a malignant neoplasm that requires early diagnosis and complete surgical excision; however, little is known about the usefulness of the detailed dermoscopic features of longitudinal melanonychia (LM) to predict the diagnosis of SMIS. To investigate the characteristic dermoscopic findings of SMIS and to establish a predictive scoring model for the diagnosis of SMIS in patients with adult-onset LM affecting a single digit. A cohort study of 19 patients with biopsy-proven SMIS and 26 patients with benign LM diagnosed in a tertiary referral hospital in Seoul, South Korea, from September 1, 2013, to July 31, 2017. Patient demographics, frequency of specific dermoscopic findings, and a predictive scoring model. Of the total 45 patients with pigmented nails, the 19 patients with SMIS included 14 women and had a mean (SD) age of 52.0 (14.4) years, and the 26 patients with benign LM included 18 women and had a mean (SD) age of 48.1 (13.2) years. Asymmetry (odds ratio [OR], 34.00; 95% CI, 3.88-297.70), border fading (OR, 9.33; 95% CI, 2.37-36.70), multicolor (OR, 11.59; 95% CI, 2.21-60.89), width of the pigmentation of at least 3 mm (OR, 5.31; 95% CI, 1.01-28.07), and presence of the Hutchinson sign (OR, 18.18; 95% CI, 2.02-163.52) were features of LM that were significantly associated with SMIS. A predictive scoring model incorporating these dermoscopic features of SMIS was assessed. The model, ranging from 0 to 8 points, showed a reliable diagnostic value (the receiver operating characteristic curve had an area under the curve [C statistic] of 0.91) in differentiating SMIS from benign LM at a cutoff value of 3, with a sensitivity of 89% and a specificity of 62%. This study suggests characteristic dermoscopic features for SMIS. A predictive scoring model based on these morphologic features may help differentiate SMIS from benign LM.

Clinical and Trichoscopic Study of Tinea Capitis versus Alopecia Areata in Pediatric Patients

AbstractBackground: Trichoscopy (hair and scalp dermatoscopy) facilitates the diagnosis of hair and scalp disorders. The aim of this study was to identify the trichoscopic features in diagnosis of Tinea Capitis (TC) and to compare these findings with those of Alopecia Areata (AA).Material and Methods: The current study included 30 patients with TC and 30 patients with AA. They were recruited from Outpatient Clinics of Dermatology and Venereology Department, Tanta University Hospitals. Clinical examination, laboratory investigations (direct microscopic examination with 10% potassium hydroxide and fungal culture) were done to confirm clinical diagnosis and dermoscopically aiming at finding the different dermoscopic features of TC and AA.Results: Short broken hairs, black dots, comma shaped hairs, corkscrew hairs and zigzag shaped hairs were observed in patients with TC. Short vellus hairs, black dots, exclamation marks, white hairs and pig tail re-growing hairs were observed in patients with AA.Conclusion: Comma shaped hairs, zigzag shaped hairs and cork screw were observed only in patients with TC. Yellow dots, exclamation mark hairs and short vellus hairs were observed only in patients with AA. Dermoscopy is rapid and reliable confirmatory test used to differentiate between TC and AA by detecting their characteristic dermoscopic features.

Dermoscopy and the diagnosis of primary cutaneous B‐cell lymphoma

Primary cutaneous B-cell lymphomas (PCBCLs) are frequently misdiagnosed, and a biopsy is needed to attain the correct diagnosis. To characterize the dermoscopic features of PCBCL. In this retrospective observational study, we analysed the pathology reports of 172 newly diagnosed PCBCL for the initial clinical differential diagnosis. The dermoscopic images of 58 PCBCL were evaluated for dermoscopic features. Two dermoscopy experts, who were blinded to the diagnosis and the study objective, evaluated images from 17 cases for a dermoscopic differential diagnosis. Of 172 biopsy-proven PCBCL lesions, cutaneous lymphoma was suspected by the clinician in 16.3%; the leading diagnosis was basal cell carcinoma in 17.4%, and other skin neoplasms in 21%. Studying 58 PCBCL dermoscopic images, we most frequently identified salmon-coloured background/area (79.3%) and prominent blood vessels (77.6%), mostly of serpentine (linear-irregular) morphology (67.2%). Dermoscopic features did not differ significantly by subtype or location. Blinded evaluation by dermoscopy experts raised a wide differential diagnosis including PCBCL, arthropod bite, basal cell carcinoma, amelanotic melanoma and scar/keloid. Two dermoscopic features, salmon-coloured area/background and serpentine vessels, are frequently seen in PCBCL lesions. These characteristic dermoscopic features, although not specific, can suggest a possible diagnosis of PCBCL.

Dermoscopic features of acral pigmented lesions in Egyptian patients: a descriptive study.

Dermoscopy is a non-invasive technique allowing rapid and magnified in vivo observation of the skin. The anatomical structure of acral volar skin results in unique dermoscopic features in this location. To describe and analyze the characteristic dermoscopic features of various kinds of acral pigmented lesions and emphasize the diagnostic value of the dermoscope in early melanoma at this anatomic site in a sample of Egyptians. This study included 200 patients with 224 acral pigmented lesions. Dermoscopic examination was done to evaluate different dermoscopic patterns of these lesions. Clinically and dermoscopically suspicious lesions for malignancy were selected for more evaluation by histopathological examination by hematoxylin-eosin staining. The most frequent dermoscopic pattern was the parallel furrow pattern, (66.1%), followed by the lattice-like (8.9%), homogeneous (7.6%), fibrillar (6.3%), non-typical (5.4%), and then parallel ridge (2.2%). The least commonly reported patterns in our cases were the reticular and globular patterns (1.8% each). There was one case of acral lentiginous melanoma of the palm with a multicomponent dermoscopic pattern. The recognition of different dermoscopic patterns is essential for diagnosis of various types of acral pigmented lesions. In addition, dermoscopy is useful in discriminating between acral nevi and early acral melanoma and narrows down the number of biopsies needed.

Characteristic dermoscopic features of melasma.

To discribe the characteristic dermoscopic features of melasma. Totally 20 patients with typical clinical presentations of melasma were included in this study. The melasma lesion and its surrounding normal skin were evaluated using dermatoscope. Melasma lesions manifested light yellow brown uniform patches in all patients, among whom dark brown patches were found in 19 patients, capillary network in 14 patients,and coarse hair in 6 patients. In contrast, no light yellow brown uniform patch was found in the normal skin in all patients (P<0.001), among whom dark brown patches were found in 10 patients (P<0.001), capillary network in 12 patients (P>0.05), and coarse hair in 2 patients (P>0.05). Light yellow brown uniform patches and dark brown patches are two major dermoscopic features of melasma.

Roles of dermoscopy in the diagnosis and differential diagnosis of scalp psoriasis and seborrheic dermatitis

To describe the dermoscopic patterns of scalp psoriasis and seborrheic dermatitis and explore the roles of dermoscopy in their diagnosis and differential diagnosis. A total of 40 patients with scalp psoriasis (n = 20) and seborrheic dermatitis (n = 20) were recruited from Department of Dermatology, Peking Union Medical College Hospital from December 2013 to May 2014. They were examined both dermoscopically and histopathologically. And characteristic dermoscopic features were evaluated. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for predefined dermoscopic criteria in relation to the diagnosis of two diseases. The most significant dermoscopic features of scalp psoriasis included dotted vessels (10/20, 50%), glomerular vessels (13/20, 65%), red loops (16/20, 80%), hairpin vessels (17/20, 85%), white scales (10/20, 50%) and punctate hemorrhages (12/20, 60%). In contrast, seborrheic dermatitis was characterized by arborizing vessels (16/20, 80%), atypical red vessels (13/20, 65%), featureless areas (20/20, 100%) and honeycomb pigment (9/20, 45%) (all P < 0.05). Scalp psoriasis and seborrheic dermatitis have different dermoscopic patterns. Dermoscopy may be valuable for clinical diagnosis and differential diagnosis of scalp psoriasis and seborrheic dermatitis.

Learning Reflectance Confocal Microscopy of Melanocytic Skin Lesions through Histopathologic Transversal Sections

Histopathologic interpretation of dermoscopic and reflectance confocal microscopy (RCM) features of cutaneous melanoma was timidly carried out using perpendicular histologic sections, which does not mimic the same plane of the image achieved at both techniques (horizontal plane). The aim of this study was to describe the transverse histologic sections research technique and correlate main dermoscopic features characteristic of cutaneous melanoma (atypical network, irregular globules and pseudopods) with RCM and histopathology in perpendicular and transverse sections in order to offer a more precise interpretation of in vivo detectable features. Four melanomas and 2 nevi with different dermoscopic clues have been studied. Lesion areas that showed characteristic dermoscopic features were imaged by dermoscopy and confocal microscopy and directly correlated with histopathology in perpendicular and transverse sections. We presented the possibility to perform transverse sections as a new approach to understand RCM features. Atypical network showed different aspects in the 2 melanomas: in one case it was characterized by pleomorphic malignant melanocytes with tendency to form aggregates, whereas in the other elongated dendritic cells crowded around dermal papillae, some of them forming bridges that resembled the mitochondrial aspect at confocal and histopathology transversal sections. Pigment globules in melanomas and nevi differed for the presence of large atypical cells in the former, and pseudopods showed up as elongated nests protruded toward the periphery of the lesion. Transverse histologic research sections have a consistent dermoscopic and confocal correlate, and it may represent an help in confocal feature interpretation and an advance in improving melanoma diagnosis and knowledge of the biology of melanocytic lesions.