Pigment Network Research Articles

Eruptive dermatofibromas in a pregnant woman

Dermatofibromas (DF) or benign fibrous histiocytofibromas represent one of the most common skin tumors. It is a soft tissue and bone tumor composed of fibroblastic and histiocytic components without nuclear pleomorphism or histological anaplasia. The eruptive form and the multiple form are 2 subunits of DF that are rare, their pathophysiology and the factors inducing its proliferation remain poorly understood. Autoimmune or neoplastic diseases are incriminated, but hormonal or toxic factors have never been elucidated. the pigmented network and the central whitish appearance is the most prominent dermoscopic pattern in the literature.

Dermoscopic features and screening strategies for the detection of small-diameter melanomas.

SummaryBackgroundAround 70% of cutaneous malignant melanomas (MMs) develop de novo, and small‐diameter or ‘tiny’ lesions are expected to represent the earliest manifestation of most MMs.AimTo describe the clinical, histopathological and dermoscopic features of tiny MMs, and to investigate the impact of imaging tools, including total body photography (TBP) and sequential digital dermoscopy imaging (SDDI) in their detection.MethodsConsecutive MMs diagnosed over 2 years in a referral centre were retrospectively included. Tiny MMs were defined as MMs with a diameter of ≤ 5 mm on dermoscopy. Dermoscopic features and the performance of four imaging methods were evaluated.ResultsOf the 312 MMs included, 86 (27.6%) measured ≤ 5 mm, and 44.2% of these were invasive. Tiny MMs were more frequently excised for being new and/or changing compared with nontiny MMs (77.9% vs. 50.9%; P < 0.001). Half of the tiny MMs would have been missed by the dermoscopic seven‐point checklist (48.2%) or the three‐point checklist (49.4%), while Menzies' method and the revised pattern analysis correctly identified respectively 65.9% and 63.5% of the tiny MMs. The most frequent positive features for tiny MMs were asymmetry in structure or colour (77.6%), brown dots (65.9%), irregular dots and globules (76.5%) and atypical pigment network (44.7%). Dermoscopic features predictive of invasion in tiny MMs were atypical vascular pattern (OR = 26.5, 95% CI 1.5–475.5, P < 0.01), shiny white lines (OR = 12.4, 95% CI 0.7–237.8, P = 0.04) and grey/blue structures (OR = 3.7, 95% CI 1.3–10.5, P = 0.01).ConclusionTiny MMs are frequently invasive and represent a clinical, dermoscopic and histopathological challenge. Dermoscopy alone has suboptimal diagnostic accuracy. Early diagnosis relies on the detection of new or changing lesions aided by TBP and SDDI.

Extrafacial Lentigo Maligna: A Clinical And Dermoscopic Analysis According to Localization.

IntroductionWhether extrafacial lentigo maligna (EFLM) differs clinically and/or dermoscopically according to location has not been analyzed in depth.ObjectivesTo evaluate clinical and dermoscopic characteristics regarding different localization in a series of EFLM.MethodsWe conducted a retrospective analysis of clinical and dermoscopic characteristics of 69 histologically proven EFLM retrieved from the database of two private institutions.ResultsOf the 69 EFLM included in the study, 25 (36.2%) were located in posterior trunk (PT), 16 (23.2%) in anterior trunk (AT), 15 (21%) in upper extremities (UE), and 13 (18.8%) in lower extremities (LE). Mean diameter among localization were as follows: 14.3 mm in PT, 11.8 mm in AT, 14 mm in UE, and 10 mm in LE (p 0.44). The most frequent dermoscopic criteria were angulated lines and tan structureless areas (70%), followed by atypical pigment network (60%), both with similar distribution among groups. Angulated lines pattern was the most frequent global pattern, observed in 55% of cases. Tan structureless/granularity pattern and patchy peripheral pigmented islands pattern were seen in 15.6% and 11.6% cases, respectively. No statistically significant differences were observed in the distribution of global dermoscopic pattern in the different localizations.ConclusionsFrom the clinical point of view, EFLM did not differ in terms of patient’s age and diameter regarding localization. Upon dermoscopy, we found no significant differences in the overall dermoscopic pattern in the different localizations.

Facial Pityriasis Alba, Polymorphous Light Eruption, and Vitiligo in Children: A Dermoscopic Distinction

Background: Hypopigmentary skin disorders are the most worrisome complaints from Indian and Indian subcontinent people. Pityriasis alba (PA), polymorphic light eruption (PLE), and vitiligo are clinically look-alike conditions commonly seen in children. Objectives: We attempted to characterize the dermoscopic features of PA and PLE and differentiate them from vitiligo in the facial region in skin of color. Methods: Dermoscopic evaluation was done using a handheld dermoscope at 10X magnification on facial lesions of a total of 60 patients with PA, PLE, and vitiligo. Dermoscopic features of all three conditions were compared and correlated with histological features. Results: Out of 60 patients, 30 (50%), 20 (33.33%), and 10 (16.66%) patients were diagnosed with PA, PLE, and vitiligo clinically and histologically, respectively. Dermoscopy of PA showed white structureless areas (100%), ill-defined margins (86%), faint brownish pigmentation (70%), and fine scales (70%) (P value = 0.001). Besides, 70% of PLE cases showed white structureless areas and ill-defined margins, and 10% showed faint brownish pigmentation (P value = 0.0001). Coarse scales and clustered dots were the most common findings (75%) in PLE lesions, followed by light brown background (60%), crusts (40%), and yellow clods (30%) (P value = 0.0001). Also, 40% and 35% of the PLE cases showed white and brown course scales, respectively (P value = 0.0001). Moreover, 13.33% of PA cases showed coarse white scales, and 3.33% showed a light brown background. All vitiligo cases showed a white glow appearance (100%), followed by perifollicular pigmentation, leukotrichia, and koebnerization shown by 40% of the cases (P value = 0.0001). Finally, 20% of the cases showed perilesional pigmentation and satellite lesions. Conclusions: PA lesions are dermoscopically characterized by ill-defined white areas with fine branny scales, whereas PLE shows coarse brown scales, ring scales, crusts, and yellow clods along with the above findings. Vitiligo lesions are devoid of scales with various pigment network abnormalities, perilesional and perifollicular pigmentation, and leukotrichia.

Solitary skin-colored nodule on a child’s face

Sir, A healthy, six-year-old boy presented with a slowly grown dome-shaped nodule on the mandibular angle region present for two years. The patient’s past medical and family history were unremarkable. A physical examination revealed a solitary, 1.3 × 1 cm, firm, painless, flesh-colored tumor (Fig. 1). Dermoscopy showed branching, serpentine vessels on a pink background (Fig. 2a). These features disappeared when slight pressure was exerted on the dermoscope and the tumor exhibited a central, white, structureless area (Fig. 2b). An excisional biopsy was performed. A microscopic examination showed a well-circumscribed, paucicellular dermal tumor composed of eosinophilic collagen bundles separated by clefts and forming a storiform pattern. Scattered fibroblasts were found among the collagen bundles. The overlying epidermis was slightly flattened (Fig. 3). The diagnosis of solitary sclerotic fibroma was established. Sclerotic fibroma (SF), also known as storiform collagenoma, is a rare benign skin tumor. It usually manifests itself as an asymptomatic, slowly growing, white-to-skin-colored papule or nodule [1]. It was first described in patients with Cowden’s disease, yet may also occur sporadically [2]. There were no mucocutaneous features of Cowden’s disease (tricholemmomas, oral fibromas, acral keratoses, palmar pits, and gingival and palatal papules) in the patient and her family members. Dermatofibroma, the main differential diagnosis of SF, usually exhibits hyperplastic changes of the epidermis instead of atrophy, and the boundaries of the lesion are unclear [2]. Only two papers have been published describing the dermoscopic findings of SF, consisting of a white background with peripheral arborizing vessels [3]. A white background may be related to an increased dermal collagen density. It is also described in dermatofibroma, typically with a peripheral pigmentation network. Although dermoscopy may improve the clinical diagnosis of SF, histopathological analysis is required.

Characterizing Malignant Melanoma Clinically Resembling Seborrheic Keratosis Using Deep Knowledge Transfer.

Simple SummaryMalignant melanomas (MMs) with aypical clinical presentation constitute a diagnostic pitfall, and false negatives carry the risk of a diagnostic delay and improper disease management. Among the most common, challenging presentation forms of MMs are those that clinically resemble seborrheic keratosis (SK). On the other hand, SK may mimic melanoma, producing ‘false positive overdiagnosis’ and leading to needless excisions. The evolving efficiency of deep learning algorithms in image recognition and the availability of large image databases have accelerated the development of advanced computer-aided systems for melanoma detection. In the present study, we used image data from the International Skin Image Collaboration archive to explore the capacity of deep knowledge transfer in the challenging diagnostic task of the atypical skin tumors of MM and SK.Malignant melanomas resembling seborrheic keratosis (SK-like MMs) are atypical, challenging to diagnose melanoma cases that carry the risk of delayed diagnosis and inadequate treatment. On the other hand, SK may mimic melanoma, producing a ‘false positive’ with unnecessary lesion excisions. The present study proposes a computer-based approach using dermoscopy images for the characterization of SΚ-like MMs. Dermoscopic images were retrieved from the International Skin Imaging Collaboration archive. Exploiting image embeddings from pretrained convolutional network VGG16, we trained a support vector machine (SVM) classification model on a data set of 667 images. SVM optimal hyperparameter selection was carried out using the Bayesian optimization method. The classifier was tested on an independent data set of 311 images with atypical appearance: MMs had an absence of pigmented network and had an existence of milia-like cysts. SK lacked milia-like cysts and had a pigmented network. Atypical MMs were characterized with a sensitivity and specificity of 78.6% and 84.5%, respectively. The advent of deep learning in image recognition has attracted the interest of computer science towards improved skin lesion diagnosis. Open-source, public access archives of skin images empower further the implementation and validation of computer-based systems that might contribute significantly to complex clinical diagnostic problems such as the characterization of SK-like MMs.

Hyperpigmented Nodular Dermatofibroma: Two Cases Report and Brief Literature Review

BACKGROUND: Dermatofibroma (DF) is a common benign skin tumor (Benign Fibrous Histiocytoma) that mostly affects the extremities with a tendency to occur more often in older females than males. It usually presents as a slow growing small brown dome shape papule on the extremities. DF has a chronic nature and can sometimes regresses spontaneously. Dermoscopy is essential in the evaluation of DF to help differentiate it with other skin tumors. The gold standard evaluation for diagnosis of DF is biopsy with histopathologic examination. Removal of DF is often due to cosmetic factors, with surgical excision being the preferred method for removal. DF has an excellent prognosis. CASE REPORT: We present two case reports of women with hyperpigmented nodules on the lower extremity. Dimple sign was positive. From dermoscopic study showed a pigment network and central white patch pattern. On histologic examination revealed proliferation of fibroblast such as spindle cells as a storiform pattern and hyperplastic epidermis with hyperpigmentation of the basal layer. Based on clinical features, dermoscopy and histopathological evaluation, the diagnosis of DF was established. Both patients were perform surgically excision and have a good result. CONCLUSION: Dermatofibroma is benign fibrous histiocytoma that represents one of the most common skin tumours. Nodular hyperpigmented dermatofibroma is a clinical variant of Dermatofibroma which can be treated with surgical excision with good prognosis.

Dermoscopic Features of Basal Cell Carcinoma and Their Association with Histological Types in A Chinese Population: A Perspective Study

Abstract Objective: The treatments and prognoses of high-risk and low-risk basal cell carcinomas are quite different. This study aimed to examine the dermoscopic features of basal cell carcinomas and assess the association between the features and basal cell carcinomas recurrence risks in a Chinese population. Methods: Patients with histopathologically confirmed basal cell carcinomas examined from March 2016 to April 2020 were enrolled. The dermoscopic features were evaluated, and the correlations between these features and the histological types and recurrence risks were assessed. Results: The study cohort comprised 119 Chinese patients with a total of 119 skin lesions. The most common dermoscopic feature of basal cell carcinomas was the absence of a pigment network (119/119, 100%), followed by shiny white streaks (105/119, 88.24%), blue-gray ovoid nests (99/119, 83.19%), multiple blue globules (78/119, 65.55%), and arborizing vessels (78/119, 65.55%); yellow-white structures were present in 29/119 lesions (24.37%). Leaf-like and spoke-wheel areas were significantly associated with superficial basal cell carcinomas (P &lt; 0.001), while arborizing vessels (P &lt; 0.001), blue-gray ovoid nests (P &lt; 0.001), and ulceration (P &lt; 0.05) were significantly associated with nonsuperficial basal cell carcinomas subtypes. The dermoscopic features of the high-risk and low-risk groups exhibited considerable overlap; however, the respective independent predictive factors for a high and low risk of basal cell carcinomas recurrence were short fine telangiectases (P &lt; 0.05) and blue-gray ovoid nests (P &lt; 0.05). Conclusion: Dermoscopy provides important information about basal cell carcinomas and is helpful in differentiating superficial basal cell carcinomas from other subtypes. The dermoscopic vascular structures and blue-gray ovoid nests play a crucial role in evaluating the basal cell carcinomas risks preoperatively.

Algorithm for the Analysis of Pigment Network Characteristics in Diagnosing Melanoma

Algorithm for the Analysis of Pigment Network Characteristics in Diagnosing Melanoma

Vulvar vitiligo and lichen sclerosus in children: A clinical challenge.

Vulvar vitiligo (VV) and vulvar lichen sclerosus (VLS), both feature skin and mucosal hypo-/depigmentation. The aim of this study was to describe the clinical and dermoscopic features of VV and VLS in the pediatric population, providing diagnostic clues, and to define their association. We performed a systematic literature review of the clinical and dermoscopic features of pediatric VV and VLS. An observational study was conducted on children affected by VLS associated with VV, referred to the Dermatology Unit of the Sant'Orsola Polyclinic in Bologna, Italy. Medical history, age at diagnosis, ethnicity, clinical and dermoscopic features, and symptoms were recorded for all patients. 124 cases of VLS and 10 cases of VV were reviewed. Clinical manifestations included hypo-/depigmented patches in both conditions, while ecchymosis/purpura and fissures/erosion were observed in VLS. Symptoms including pruritus, pain, or burning were reported only by VLS patients. In our study five patients with VLS associated with VV were retrieved. Clinical features included well-demarcated depigmented patches in VV and translucent areas, erythema, ecchymoses/purpura, and labial fusion in VLS. Dermoscopy showed white structureless areas with a whipped cream-like appearance, linear or dotted vessels, white chrysalis-like structures, erosion and red-purpuric blotches in VLS and reduced pigment network or pigment absence, intralesional spots of residual pigmentation and telangiectasias in VV. Symptoms were present in all patients. Both VV and VLS show hypo-/depigmented patches. In the presence of associated symptoms, possible VLS should be investigated with clinical and dermoscopic examination to achieve a prompt diagnosis.

Dermatoscopic assessment of treatment response in patients undergoing autologous non-cultured epidermal cell suspension for the treatment of stable vitiligo: A prospective study.

There is lack of literature on serial dermatoscopic assessment in patients undergoing non-cultured epidermal cell suspension (NCES) for treatment of stable vitiligo. This prospective study was conducted to evaluate the role of serial dermatoscopy in assessing disease stability and predicting repigmentation rates in vitiligo patients undergoing NCES. Dermatoscopic assessment of target lesions were done at baseline and post-NCES at week 4, 8, 12, 16, and 24. Patches obtaining >90% repigmentation at 24 weeks were categorized to have obtained excellent repigmentation. The dermatoscopic features of target lesions that showed clinical signs of disease activity anytime during the follow-up period were compared to those maintaining clinical stability throughout. Twenty-six vitiligo patients with 52 patches, clinically stable for atleast 1year were recruited. At follow-up, six patches showed clinical signs of instability. Five patches in the unstable group developed satellite lesions by week 16, compared to none in the stable group (p <0.05). Excellent repigmentation was achieved in 29 out of 52 patches. Appearance of normal reticular pigment network at 8 weeks was a positive predictor of excellent response (OR=10.5, CI 1.2-89.7), whereas, altered pigment network at 12, 16, and 24 weeks and telangiectasias at 12 and 16 weeks significantly reduced the odds of excellent repigmentation.

Dermatoscopic Features of Naevi During Pregnancy-A Mini Review.

Changes in melanocytic naevi and development of new naevi have been reported in pregnant women. The association between pregnancy and melanoma is a controversial topic. We conducted this review to identify the dermatoscopic changes that occur in naevi during pregnancy that could facilitate in distinguishing benign from suspicious lesions. Medline, Scopus, and Embase datasets were reviewed for clinical studies on dermatoscopic characteristics of melanoma and naevus in pregnancy. Six cohort studies with a total of 258 patients with 1,167 skin lesions that were examined fulfilled the conditions to be included in the review. None of the patients developed melanoma. Development of new naevi, when reported, was observed in less than half of the participants. The most frequent observed dermatoscopic change among the studies was the increase in the number of dots. Development of new vessels, hypo- and hyperpigmentations and changes in the pigment network were common described changes. The included studies were heterogeneous not allowing head-to-head comparisons between them. Robust and larger studies of dermatoscopic evaluation of naevi in pregnant women are needed to determine high-risk dermatoscopic characteristics.

A study of wood’s lamp findings in melasma

Introduction: Melasma is main cause of facial hyperchromia and has a significant psychosocial impact. Wood’s lamp has been a useful device to estimate the depth of melanin determined by light-induced fluorescence. A dermoscope enables a clear visualization of pigments distribution, and the color variation of melanin will depend on its location within the skin. Methods: A cross-sectional observational study was conducted at the outpatient section of the Department of Dermatology of a tertiary care teaching hospital. A total of 120 patients were enrolled for a duration of 1 year. Patients diagnosed to have melasma on clinical grounds were enrolled after considering various inclusion and exclusion criteria. Result: On clinical examination, 47 patients had centrofacial distribution and 73 had malar distribution of melisma. On Wood’s lamp 51 patients showed complete enhancement hence classified as epidermal, 63 patients had no enhancement hence classified as dermal and 6 patients showed few areas of enhancement and hence classified as mixed melasma. On dermoscopy, 48 patients showed regular pigment network with a brownish homogeneous pigmentation hence classified as epidermal, 61 patients showed Irregular network with bluish grey pigmentation hence classified as dermal and 11 patients showed features of both epidermal and dermal and hence classified as mixed melasma. Conclusion: In the analysis of correlation between Dermoscopy and Wood’s lamp in classification of Melasma, the results showed substantial discordance between the methods. Based on the principles of Dermoscopic examination, this method applicable, more appropriate and helpful for routine diagnosis, assessment and monitoring of patients with melasma.

A Study on Pattern of Dermatoses Affecting Periorbital Region and its Clinicodermoscopic Correlation

Background: The periorbital area may be affected by a vast number of dermatoses such as infectious or noninfectious diseases, inflammatory dermatoses, systemic diseases, drug reactions, benign and malignant lesions, and traumatic lesions, thus poses both diagnostic and therapeutic challenge. Objectives: To study the pattern of dermatoses involving periorbital region and to correlate its clinical and dermoscopic findings. Materials and Methods: A cross-sectional study was carried out in patients with periorbital dermatoses (PODs) attending the Department of Dermatology during April 2018–March 2019 after approval from the ethical committee. A detailed history was taken and investigations including hemoglobin levels, Vitamin B12, serum cholesterol, and wood's lamp examination were done as and when required. A prestructured pro forma was used to collect the data. Data were entered into Microsoft Excel 2010 and analyzed using EPI INFO. Ver7 software (Developed by united states of America centre for disease control. Results: A total of 275 patients were studied of which majority of patients belonged to the age group of 41–60 years (38.5%) with a female-to-male ratio of 1.16:1. The most common group of PODs was skin tumors (25.1%), followed by disorders of pigmentation (17.4%), infections (13.1%), and periorbital dermatitis (11.6%). Most common dermoscopy findings of PODs were as follows: (a) common seborrhoeic keratosis (CSK): comedone-like opening, fissures and ridges, and sharp demarcation; (b) verruca vulgaris: finger-like papilla, red brown dots in center of papilla; (c) periorbital hyperpigmentation: blotches, globules, exaggerated pigment network, and reticular vessels; (d) allergic dermatitis: patchy red dots, pinkish hue, and patchy scale; (e) senile comedone: comedone-like opening; and (f) xeroderma pigmentosus: orange–yellow homogenous structures. Conclusion: Periorbital region is an area of cosmetic concern. Dermoscopy improves the differential diagnosis of common PODs and its knowledge may aid to reduce unnecessary invasive procedures such as shaving or incisional biopsies which may lead to scarring.

Melanocytic lesions ≤ 6mm: Prospective series of 481 melanocytic trunk and limb lesions in Brazil.

Early diagnosis when melanoma is still small and thin is essential for improving mortality and morbidity. However, the diagnosis of small size melanoma might be particularly difficult, not only clinically but also dermoscopically. This study aimed to define clinical and dermatoscopic parameters in the diagnosis of suspicious pigmented cutaneous lesions with a diameter of ≤ 6mm and determine the sensitivity, specificity, positive and negative predictive values as well as the accuracy of each clinical and dermatoscopic criterion. This is a transversal, descriptive and analytical study of dermatoscopic analysis with the gold standard being the pathologic examination obtained from the excisional biopsy of suspicious melanocytic lesions with a diameter of ≤ 6mm. Trunk and limb lesion data from a public health service and a private clinic were prospectively collected from 2011 to 2017 by a unique observer. In total, 481 melanocytic lesions were included, with 73.8% being ≤ 4mm in diameter. Overall, 123 were diagnosed as melanoma, 56.0% in situ and 22.0% as thin melanomas (Breslow index 0.1 to 1.0mm). Melanoma presented symmetry in 53.7% of cases, regular borders in 54.5% and a single color in 60.2%. Regarding evolution, 13.8% of melanomas versus 10.9% of benign lesions (p = 0.116) were new by comparing photos from baseline with photos from the follow-up. The majority of melanomas (65%) were found on the limbs compared to 37.2% of the benign lesions at this location (p<0.001). A multiple logistic regression model adjusted for age, gender and location was created. The independent variables associated with the diagnosis of melanoma ≤ 6mm, adjusted for age, gender and location, were: streaks (adjusted Odds Ratio [aOR] 2.5; 95% CI 1.3–4.7; p = 0.006), and the presence of a structureless area (aOR 2.2, 95% CI 1.2–4.0, p = 0.011). Conversely, a symmetric typical pigment network was a protection variable (aOR 0.4, 95% 0.7–0.9, p = 0.040). In conclusion, dermatoscopic criteria have been identified which help to diagnose cases of small size melanoma. These include streaks and structureless areas that can be taken, particularly in consideration for the diagnosis of this subset of small difficult melanomas.

Solitary mastocytoma in children: a retrospective analysis of the clinical course and timing of regression

Introduction. Solitary mastocytoma is a rare clinical variant of cutaneous mastocytosis that makes its debut in infancy and early childhood. Сhanges in clinical manifestations at different ages and the rate of regression of the disease are insufficiently covered in the literature.Aim. To study the clinical manifestations and timing of regression of solitary mastocytoma in children, through retrospective analysis.Materials and methods. We retrospectively reviewed data from 32 children aged 3 months to 9 years who were on outpatient treatment and observation at the State Budgetary Healthcare Institution “Moscow Scientific and Practical Center of Dermatovenereology and Cosmetology of Moscow Health Department” in the period from 2016 to 2020 inclusive. Diagnosis information obtained from medical records.Results and discussion. The average age of disease onset was 2.5 ± 0.7 months. Solitary mastocytoma was observed more often in boys than in girls (1.4:1). In 81.2% of children, solitary mastocytoma clinically regressed before the age of 6 years. Delayed regression of rashes in the age range from 6 to 9 years was observed in 18.8% of children. Late correct diagnosis, lack of timely recommendations for care and treatment, traumatization of elements are factors that slow down the regression of the disease. Dermatoscopic examination can be used for dynamic observation of mastocytoma, since the patterns in the foci of regression differ from mature mastocytomas in the absence of yellow-orange areas. A pronounced brown pigment network on a yellow background can be a sign of the activity of the process and a reason for the appointment of symptomatic therapy.Conclusion. The clinical features of the modern course of solitary mastocytoma are the tendency to multiple rashes, the variety of localization and the long-lasting positivity of the Darier sign. Obviously, clinical monitoring using dermatoscopy and laboratory research methods allows to follow-up the activity of the process and promptly adjust drug treatment. To prevent delayed regression of solitary mastocytoma, traumatization of rashes of any localization should be excluded.

Dermoscopic Predictors of Tumor Thickness in Cutaneous Melanoma: A Retrospective Analysis of 245 Melanomas.

The literature regarding the association of dermoscopic structures with Breslow thickness in melanoma is scarce, limited to small case series, and mostly outdated. This study determined the dermoscopic patterns, colors and structures that are associated with melanoma in situ, thin melanomas (<0.8 mm) and thick melanomas potentially requiring sentinel lymph node biopsy according to current guidelines (≥0.8 mm). A retrospective evaluation of 245 dermoscopic images of primary cutaneous melanoma located on the trunk or limbs was performed by consensus of 2 dermoscopists. Red-pink, blue-gray and white color, blue-white veil, shiny white streaks, irregular vessels, blue-black pigmentation, milky red areas, pseudolacunae, ulceration and rainbow pattern were associated with thickness ≥0.8 mm, whereas atypical pigmented network, regression and hypopigmented areas were significantly associated with early melanomas. This is a retrospective study performed in a single institution. Melanomas of special sites were excluded from our evaluation. Dermoscopy is based on subjective evaluations that depend largely on the observers' experience. The identification of certain dermoscopic structures and colors might help in the discrimination between thin and thick melanomas.

Dermoscopic Features of Mycosis Fungoides and Its Variants in Patients with Skin of Color: A Retrospective Analysis.

Mycosis fungoides (MF) is a cutaneous T-cell lymphoma that disproportionately affects people with skin of color and is difficult to diagnose. This study characterized the dermoscopic features of MF and its subtypes in patients with skin of color. Dermoscopic images of patients with skin of color seen at the cutaneous T-cell lymphoma clinic at Michigan Medicine Dermatology between 2018 and 2019 were reviewed. Specific dermoscopic features were identified and summarized for each subtype of MF. A total of 33 dermoscopic images from 11 patients with skin of color were reviewed. Four patients had classic MF (18 dermoscopic images), 4 had hypopigmented MF (9 dermoscopic images), 1 had folliculotropic MF (4 dermoscopic images), and 2 had verrucous MF (2 dermoscopic images). Classic MF was characterized by striking pigmentary change, thick black lines, white rosettes, and geometric white lines. Hypopigmented MF was characterized by the loss of the patient's natural pigment network. In folliculotropic MF, follicular plugging and hyperpigmented to violaceous perifollicular halos were observed. In verrucous MF, large, yellow-gray amorphous structures with yellow-gray ridges and comedo-like openings were observed within hyperkeratotic areas. Overall, vessel morphology was difficult to discern on dermoscopy. Dermoscopic features of MF in patients with skin of color are predominantly characterized by striking pigmentary alteration. Vessel morphology is not a reliable diagnostic feature. As patients with MF and skin of color have a worse prognosis than light-skinned individuals, a better understanding of dermoscopic features may aid in early diagnosis and improve outcomes in this group.

Diagnostic efficiency of the main dermatoscopic symptoms and algorithms for detecting skin melanoma

AIM: to assess the diagnostic accuracy of the main dermatoscopic signs and algorithms used to diagnose skin melanoma.&#x0D; MATERIALS AND METHODS: To assess the diagnostic effectiveness of the performed dermatoscopy in detecting skin melanoma, the main dermatoscopic signs that occur in this disease were identified: atypical pigment network, atypical globules, asymmetry of pigmentation and structure, asymmetric stripes, asymmetric zones of hyperpigmentation (spots), blue-white (white-blue) veil, graininess, scar-like foci of depigmentation, white shiny stripes, negative pigment network. The study was carried out based on the analysis of 34 archival dermatoscopic images of melanocytic skin lesions with a morphologically verified diagnosis (11 melanomas and 23 melanocytic nevi). In addition, a comparison was made of the indicators of the diagnostic efficiency of two main dermatoscopic algorithms used in the diagnosis of skin melanoma: the algorithm by 3 signs and by 7 signs. For this, 186 archived dermatoscopic images of melanocytic skin lesions were analyzed. All patients included in the study were examined and treated at the clinic for skin and venereal diseases in the period from 2015 to 2019. The study was carried out using a HEINE DELTA 20 Plus dermatoscope in immersion mode and in cross-polarization.&#x0D; RESULTS: The following dermatoscopic features had the highest diagnostic efficiency for the diagnosis of skin melanoma: blue-white veil (86.8%), asymmetry of pigmentation and structure (82.6%), and white shiny stripes (72.8%). The diagnostic efficiency of the 3 signs algorithm was 93.0%, the 7 signs algorithm 90.5%.&#x0D; CONCLUSION: Diagnostic algorithms for confirming melanoma can be successfully used by both general practitioners and medical specialists (dermatologists, oncologists). In this case, it is preferable to use the three signs algorithm at the initial admission of patients as a screening option, and the seven-signs algorithm by experienced specialists in the field of dermatoscopy to confirm the diagnosis (4 figures, 3 tables, bibliography: 11 refs).

The differences in clinical and dermoscopic features between in situ and invasive nevus-associated melanomas and de novo melanomas.

Nevus-associated melanomas (NAM) account for 30% of all melanomas and are associated with younger age and with thinner Breslow thickness. Previous studies of NAM dermoscopy found conflicting results. To compare the clinical and dermoscopic features of NAM and de novo melanomas (DNM), stratified by melanoma thickness, in a relatively large cohort of patients. A cross-sectional study of all melanomas biopsied between 2004 and 2019 at a large cancer centre. Lesions were categorized as in situ and invasive NAM or DNM. Dermoscopic images were reviewed and annotated. Associations between melanoma subtype and dermoscopic features were analysed via logistic regression modelling. Bivariate analyses were conducted using non-parametric bootstrap and chi-squared methods. The study included 160 NAM (86 in situ and 74 invasive) and 218 DNM (109 in situ and 109 invasive). NAM were associated with younger age, greater likelihood of being present on the torso, and thinner Breslow thickness. NAM were 2.5 times more likely to show a negative pigment network than DNM. In situ NAM were 2.1 and two times more likely to display dermoscopic area without definable structures and tan structureless areas than DNM, respectively. In situ melanomas were more likely to present a pigment network, and invasive melanomas more commonly presented scar-like depigmentation and shiny white structures. Streaks, blotches and shiny white structures were associated with deeper Breslow depth. Even though the nevus component of NAM could not be identified dermoscopically in the current series, negative pigment network, tan structureless areas and areas without definable structures are dermoscopic clues for NAM.