Three years dermoscopic follow‐up of atypical nevi

Atypical nevi are dynamic lesions and may progressively transform into more or less atypical lesions. We aimed to investigate the dermoscopic features of atypical nevi and dynamic changes in these lesions over a period of 3‐years. Patients with 3‐year dermoscopic follow‐up records were enrolled in the study. We compared the dermatoscopic features of the nevus recorded in the first dermoscopic examination and at the end of the third year. Changes in size (mm), pattern, and color were investigated. The most common dermoscopic patterns were reticular (18 patients; 34%), reticular‐homogeneous (17 patients; 32.1%), and reticular‐globular (7 patients; 13.2%). The most common pigmentation patterns were central hyperpigmentation (28 patients; 52.8%), regular pigmentation (nine patients; 17.0%), and multifocal hypo/hyperpigmentation (eight patients; 15.1%). Twenty‐one (39.6%) patients showed changes in pattern. The transformation from reticular‐homogeneous pattern to the homogeneous pattern was the most frequent change in pattern (7 of 21 patients; 33.3%). The transformation from reticular pattern to reticular‐homogeneous pattern was the second most common change in pattern (5 of 21 patients; 23.8%). Fourteen (26.4%) patients experienced symmetrical enlargement. Symmetrical enlargement was statistically more frequent in patients who showed dermoscopic changes in pattern than in those who did not show any changes in the pattern (p: .038). In this study, we did not observe any new dermoscopic clues for the diagnosis of melanoma during the follow‐up. The nevi tended to turn into a homogeneous (structureless) pattern. We observed that the most common dermoscopic change in pattern was the transformation from reticular‐homogeneous pattern to homogeneous pattern, and the lesions had symmetrical enlargement during this transformation. In conclusion, despite the known association between atypical nevi and the risk of developing melanoma, most atypical nevi do not transform into melanoma. Therefore, our study suggests that the excision of atypical nevi is not necessary and dermatoscopic follow‐up can reduce the number of unnecessary excisions.     

Videodermoscopic pattern analysis of acral melanocytic nevi

Three major and three minor types of acral melanocytic lesions have been described: parallel furrow, lattice-like, fibrillar, reticular, homogeneous and globular. To examine the dermoscopic patterns of acral melanocytic lesions and to investigate the association of these patterns with clinical features. This study included 419 acral melanocytic lesions of 295 patients. Dermoscopic images were stored in a standardized digital system and assessed. The incidence rates of the patterns were as follows: parallel furrow (62.5%), reticular (12.2%), globular (7.6%), fibrillar (5.0%), lattice-like (4.3%), homogeneous (3.8%), non-typical (3.8%), globulostreak-like (0.5%) and parallel ridge (0.2%). There was a significant association between pattern and diameter; nevi showing globular pattern were significantly smaller than those showing lattice-like pattern. There was a significant correlation between pattern and localization. The fibrillar pattern was observed more commonly on the feet, and the lattice-like pattern was seen almost entirely on the hands. Homogeneous and globular patterns were proportionately more common on the feet than on the hands. A significant association was found between patterns and colors. Compared with the lattice-like pattern, parallel furrow, fibrillar and homogeneous patterns were lighter in color; the globular pattern was darker than the homogeneous pattern. There was no significant correlations between pattern and clinical presentation. In conclusion, unlike all other studies, in the present study, the two most common patterns following the parallel furrow pattern were reticular and globular, which are minor patterns. Besides the differences in pattern distribution and inherent variability in individual assessment, the age of the study group and location of nevi influence the pattern, possibly in association with race.     

Natural History of Atypical and Equivocal Melanocytic Lesions in Children: An Observational Study of 19 Cases

Digital dermoscopy follow‐up helps to identify patterns of change typical of common atypical nevi and early melanoma and improves the follow‐up of patients with atypical nevi. We report the morphologic changes observed over time in 19 atypical or equivocal acquired melanocytic nevi that underwent dermoscopic follow‐up. Two observers retrospectively examined digitalized dermoscopic images of 19 atypical melanocytic nevi from 15 children and young adults (median age 12 years, range 3–26 years). The images were assessed for global dermoscopic patterns at baseline and after a median 25‐month (range 6–138 mos) follow‐up. Ten (52.6%) nevi changed and nine (47.4%) retained a stable dermoscopic pattern. Of the 10 changing lesions, 2 of 4 homogeneous nevi evolved into a reticular pattern and 2 into a mixed pattern; 1 of 2 nevi with a mixed pattern evolved into a homogeneous nevus and 1 into a regressing nevus; 1 of 2 nevi with “other” patterns, such as negative pigment network and peppering throughout the lesion, evolved into a mixed nevus and 1 into a regressing nevus; 1 globular nevus evolved into a mixed pattern; and 1 starburst nevus evolved into a homogeneous nevus. The most striking results of our study were that atypical nevi can evolve into common nevi or they can regress, as documented by long‐term dermoscopic follow‐up. In children and young adults, dermoscopic follow‐up of atypical nevi might be a valid alternative to surgical excision and enables us to achieve new insights into the natural history of these nevi.     

Dermoscopic classification of atypical melanocytic nevi (Clark nevi).

OBJECTIVES: To create a dermoscopic classification of atypical melanocytic nevi (Clark nevi) and to investigate whether individuals bear a predominant type. DESIGN: Digital dermoscopic images of Clark nevi were classified according to structural features, ie, reticular, globular, or homogeneous patterns or combinations of these types. The nevi were also characterized as central hypopigmented or hyperpigmented, eccentric peripheral hypopigmented or hyperpigmented, or multifocal hypopigmented or hyperpigmented. SETTING: Two pigmented skin lesion clinics. PATIENTS: We examined 829 Clark nevi on 23 individuals. MAIN OUTCOME MEASURE: A reliable dermoscopic classification of Clark nevi and frequency of different dermoscopic types. RESULTS: Using the dermoscopic classification, the 829 Clark nevi were classified as follows: 221 (26.7%) as reticular, 167 (20.1%) as reticular-homogeneous, 148 (17.9%) as globular-homogeneous, 112 (13.5%) as reticular-globular, 89 (10.7%) as homogeneous, 84 (10.1%) as globular, and 8 (1.0%) as unclassified. Most individuals were prone to a predominant type of Clark nevus. Seven individuals (30%) showed a single type of Clark nevus in more than 50% of their nevi and 5 (22%) in more than 40% of their nevi. CONCLUSIONS: The proposed dermoscopic classification of Clark nevi is easily applicable and allows a detailed characterization of the different dermoscopic types of Clark nevi. Knowledge of these dermoscopic types should reduce unnecessary surgery for benign melanocytic lesions. Exact classification of the different types of Clark nevi is a necessary prerequisite for further clinical, dermoscopic, and histopathologic studies, which will give new insights in the biology of acquired melanocytic nevi.     

Dermoscopic patterns and subclinical melanocytic nests in normal-appearing skin

Background  Dermoscopic patterns of normal-appearing skin have received little scrutiny. We have recently completed an analysis of dermoscopic patterns of naevi in children.
Objectives  To describe dermoscopic patterns in the normal-appearing skin surrounding naevi and to explore histological features of patterned background skin.
Methods  Dermoscopic images of back naevi were obtained from a population-based sample of fifth grade students. The dermoscopic pattern of the background skin around the naevi was analysed. We examined histopathological features of background skin patterns in a convenience sample of seven specimens from six adult patients.
Results  We observed a dermoscopic pattern in the background of normal-appearing skin in 41% of 1192 dermoscopic images from the backs of the 443 children. The background skin pattern was less frequent in individuals with a fair skin ( P  <   0·001). A globular pattern was observed in 201 images (17%) and a reticular pattern was seen in 287 images (24%), of which 112 images also showed globules. Inter-rater reliability between the two observers for a random sample of 100 images was excellent (κ = 0·77). In four specimens with a globular background pattern, microscopic melanocytic nests were observed in the normal-appearing skin. No subclinical naevus nests were observed in three reticular pattern specimens.
Conclusions  Dermoscopically recognized patterns are commonly present in clinically normal skin of children. Microscopic melanocytic nests may be observed in normal-appearing skin with a globular skin pattern.     

Clinical and dermoscopic features of small Reed nevus (<6 mm)

Background The differential diagnosis between Reed nevi and melanoma becomes more difficult if the lesion to analyse presents a small size, with a diameter of 6 mm or smaller. Many studies have reported various dermoscopic features of Reed nevi during their growth phases. In early stages of evolution, the lesions generally show a characteristic globular appearance typically found in childhood, followed by the so‐called starburst pattern. Objective The aim of the study was to identify the main dermoscopic features in small Reed nevi (<6 mm in size). Methods Using a computerized skin‐imaging database for melanoma prevention surgery at the Department of Dermatology of the University of Florence, 15 Reed nevi were selected among 103 small (<6 mm) melanocytic lesions consecutively excised. Images of small Reed nevi, independently blinded to histopathological diagnosis, were administered to a dermatologist expert in dermoscopy, who separately examined the clinical and the dermatoscopic images of small Reed nevi and evaluated their clinical and dermoscopic parameters. Results Analysis of the main dermoscopic patterns showed that 40% had a reticular pattern, 20% had a starburst pattern, 6.5% had a globular pattern, 6.5% had a homogeneous pattern and 27% had an atypical pattern. Conclusion We propose that small, early‐stage Reed nevus are not characterized by an evolution of growth patterns to a phenotype typical of larger lesions. We assume that the patterns are distributed in a linear manner between age groups, may all be present at the outset and thus are independent from the various stages of nevus development.     

Dermoscopic patterns of acral melanocytic nevi and melanomas in a white population in central Italy

OBJECTIVE: To investigate the dermoscopic features of acral melanocytic lesions in a white population in central Italy. DESIGN: Retrospective review. SETTING: University dermatology department. PATIENTS: Six hundred fifty-one Italian subjects, ranging in age from 6 months to 78 years. MAIN OUTCOME MEASURES: We retrospectively investigated all digital dermoscopic images of acral melanocytic lesions included in our database from January 1996 to May 2005. RESULTS: We retrieved digital images of 723 benign acral melanocytic lesions in 641 patients (235 males and 406 females; mean age, 26.5 years) and of 10 acral melanomas in 10 patients (7 males and 3 females; mean age, 65 years). Individual lesions were located on the soles (n=520), fingers (n=146), and palms (n=67). Among acral nevi, the parallel furrow (42.1%) was the most common pattern, followed by the latticelike (14.9%), nontypical (13.7%), fibrillar (10.8%), homogeneous (9.3%), globular (5.4%), and reticular (2.1%) patterns. The frequency of distribution of the latticelike, nontypical, fibrillar, and homogeneous patterns significantly differed (P<.001, P=.03, P<.001, and P=.03, respectively) between anatomical sites. Also, 13 acral nevi (1.8%), mainly located on the fingers, showed a new combined pattern (transition pattern) consisting of a brownish black network associated with a parallel furrow or latticelike pattern. All 10 acral melanomas showed a multicomponent dermoscopic pattern. CONCLUSIONS: In our series of acral nevi, we observed 8 dermoscopic patterns, with varying distribution by anatomical site. Identification of a specific pattern is highly suggestive of the benign or the malignant nature of any given acral melanocytic lesion.     

Seguimiento digitalizado combinado en población con alto riesgo de desarrollar un melanoma maligno: análisis retrospectivo de 152 pacientes

BackgroundDigital dermoscopy (DD) has been found to improve the accuracy of melanoma diagnosis in high-risk patients. A 2-step approach combining DD and total-body photography (TBP) can facilitate the detection of new lesions or early macroscopic changes in existing lesions.ObjectivesThe aim of this study was to determine the number of biopsies needed to diagnose melanoma and to describe the clinical and dermoscopic characteristics of melanoma diagnosed in patients with pigmented lesions under follow-up with DD and TBP.Patients and methodsRetrospective study of 152 patients with a high risk of melanoma who were followed using a 2-step digital approach at Hospital del Mar in Barcelona, Spain, between 2002 and 2016. We analyzed the characteristics of pigmented lesions excised after macroscopic changes were detected by periodic DD and TBD.ResultsBiopsy results of 99 lesions (84 dysplastic nevi, 13 melanomas, and 2 compound melanocytic nevi) showed a ratio of benign melanocytic lesions to melanomas of 1:6.6. The mean Breslow thickness was 0.19 mm. Macroscopic changes were significantly more common in melanomas than in melanocytic nevi (P = 0.018). Dermoscopic findings associated with melanoma were asymmetric growth and focal structural changes (P < 0.001). The specific features associated with a diagnosis of melanoma were asymmetry (P < 0.001), a reverse pigment network (P = 0.011), atypical globules (P = 0.011), and polymorphous vessels (P = 0.045).ConclusionsTBP follow-up is a useful tool for the early diagnosis of melanoma. In our series, 50% of melanomas diagnosed during digital follow-up were detected by observation of a new lesion via TBP mapping or macroscopic changes in an existing lesion. Dermoscopic follow-up is essential in patients at high risk for melanoma as both melanocytic nevi and melanoma show a range of specific dermoscopic features, and a diagnosis of melanoma can only be based on a record of changes in the appearance of lesions during follow-up.     

Microscopia confocal de reflectancia: una herramienta útil para diagnosticar malignidad en lesiones melanocíticas que presenten el signo de la isla

The dermoscopic island is described as a well-defined area in a melanocytic lesion, with a different dermoscopic pattern from the rest of the lesion. It is predictive of melanoma, particularly when the pattern of the island is atypical. We present the reflectance confocal microscopy (RCM) findings in 3 lesions with dermoscopic islands: nevus-associated melanoma, melanocytic nevus, and in situ melanoma. The nevus-associated melanoma and in situ melanoma presented cellular atypia (atypical cells in isolation or forming nests) and architectural distortion on RCM. The nevus presented a dermoscopic island with a typical globular pattern with dense nests and no atypia on RCM. Dermoscopic island is mainly associated with in situ and nevus-associated melanomas. RCM offers good cellular resolution to the depth of the reticular dermis and is useful for diagnosing of melanomas presenting a dermoscopic island.     

Age-related prevalence of dermoscopy patterns in acquired melanocytic naevi

BACKGROUND: Based on the dermoscopic classification of acquired melanocytic naevi, six different dermoscopic types can be distinguished by morphology (globular, globular-reticular, globular-homogeneous, reticular, reticular-homogeneous, homogeneous) and by pigment distribution (uniform, central hyperpigmentation, central hypopigmentation, peripheral hyperpigmentation, peripheral hypopigmentation, multifocal hyper/hypopigmentation). It has been suggested that most individuals harbour one predominant dermoscopic type among their naevi. OBJECTIVES: To evaluate whether the age of the patient influences the predominant naevus pattern observed in individuals with multiple acquired melanocytic naevi. METHODS: Individuals were recruited from the pigmented skin lesion clinic in Graz between July 2000 and February 2001. Individuals with at least 10 melanocytic naevi were selected consecutively until a total of 10 individuals in each of five age groups was obtained. Age groups were: 0-15 years, 16-30 years, 31-45 years, 46-60 years and > 60 years. Digitized images of acquired melanocytic naevi, defined as benign melanocytic proliferations having a diameter of at least 5 mm with a macular component and which were not apparent within the first year of life, were evaluated by dermoscopic criteria. The associations of dermoscopic features as a function of patient age were analysed. We calculated absolute numbers and frequencies, given as percentages, as well as predominance of the dermoscopic types of naevi in the different age groups. RESULTS: Analysis of 1268 naevi revealed that the globular pattern predominated in the youngest age group. By contrast, the reticular and/or homogeneous patterns were increasingly exhibited in naevi from older individuals (older than 15 years). Uniform pigmentation was most common in melanocytic naevi in the youngest age group, while central hyperpigmentation was predominantly seen in the group of individuals aged 16-30 years. CONCLUSIONS: The predominance of dermoscopic types of melanocytic naevi varies according to the individual's age. Awareness of the age-related dermoscopic predominance of melanocytic naevi might allow more accurate recognition of dermoscopic patterns of melanocytic skin lesions that are unusual with respect to the individual's age. This observation may help in the early recognition of some 'banal'-appearing melanomas. Furthermore, the observations made in this study raise interesting questions regarding naevus evolution.     

Spitz Nevi and Other Spitzoid Neoplasms in Children: Overview of Incidence Data and Diagnostic Criteria

Spitz nevi are benign melanocytic neoplasms characterized by epithelioid or spindle melanocytes or both. In some rare cases their presentation overlaps with the clinical and histopathologic features of malignant melanoma, so a differential diagnosis can be difficult to make. Intermediate forms between Spitz nevi and malignant melanoma, with unpredictable behavior, have been called atypical Spitz tumors. A literature search was performed to review the clinical, dermoscopic, genetic, and histopathologic aspects of spitzoid tumors. Spitz nevi mainly occur in children, with no predilection for sex, and in young women. Common sites are the head and lower arms, where Spitz nevi present as pink nodules or hyperpigmented plaques. Spitzoid lesions may have diverse dermoscopic patterns: vascular, starburst, globular, atypical, reticular, negative homogeneous, or targetoid. The management of spitzoid lesions can be invasive or conservative; surgical excision is usually reserved for those with doubtful features, whereas clinical and dermoscopic follow‐up is preferred for typical pediatric Spitz nevi. The role of sentinel lymph node biopsy in atypical Spitz tumors is debated. Immunohistochemistry and new molecular techniques such as comparative genomic hybridization, polymerase chain reaction, and fluorescence in situ hybridization offer new diagnostic perspectives, investigating genetic alterations that are specific for malignant melanoma or for Spitz nevi.     

Dermoscopic naevus patterns in people at high versus moderate/low melanoma risk in Queensland

Introduction: Dermoscopic understanding of naevus characteristics is essential baseline knowledge for identifying early malignant changes. Method: This cross‐sectional study includes 34 patients (56% female, mean age 48 years) at high risk of melanoma (personal or a first degree family member with history of melanoma) and 31 moderate/low melanoma risk volunteers (55% female, mean age 37 years) recruited at the Princess Alexandra Hospital, Brisbane, between October 2009 and March 2010. Participants received full body and individual dermoscopic imaging of clinically significant naevi (≥2 mm on the back of male/female and lower limbs of female and ≥5 mm at other body sites). Dermoscopic patterns of naevi were compared between people at high versus moderate/low melanoma risk according to age and body site. Results: In both high and moderate/low risk groups, globular naevi predominated on the head/neck and abdomen/chest, reticular and non‐specific naevi on the back, and non‐specific pattern on the upper and lower limbs. Non‐specific naevi were the most common in all age groups. In both risk groups, globular naevi were more frequent in the younger age bracket, and reticular naevi were more frequent in the older age bracket. Mixed naevus patterns were infrequent and were more common in the younger age brackets of both risk groups. Conclusion: Our preliminary data shows that dermoscopic naevus patterns were similar for age and body site in people at different levels of melanoma risk, suggesting high melanoma risk does not influence dermoscopic naevus patterns.     

Dermoscopy patterns of halo nevi

BACKGROUND: Halo nevi (HN) are benign melanocytic nevi surrounded by a depigmented area (halo). This study aims to evaluate the dermoscopic features of HN and their changes during digital dermoscopic follow-up and to investigate the frequency of the halo phenomenon in a series of melanomas. OBSERVATIONS: In a retrospective study, digital dermoscopic images of HN from patients who attended the Pigmented Skin Lesions Clinic of the Department of Dermatology, Medical University of Graz, between October 1, 1997, and March 31, 2004, were reviewed and classified by dermoscopic morphologic criteria. For HN that were followed up with digital dermoscopy, the percentages of changes in the size of the nevus and halo components were calculated. In addition, digital dermoscopic images of histopathologically confirmed melanomas obtained from the same database were reviewed for the presence of an encircling halolike depigmentation. We classified 138 HN in 87 patients (mean age, 22.4 years). The most common dermoscopic structures were the globular and/or homogeneous patterns in more than 80% of HN. Follow-up of 33 HN revealed considerable size reduction of the nevus component, but this was not associated with significant structural changes. Of a total of 475 melanomas, only 2 revealed an encircling halo, but both displayed clear-cut melanoma-specific patterns according to dermoscopy. CONCLUSIONS: Halo nevi exhibit the characteristic dermoscopic features of benign melanocytic nevi, represented by globular and/or homogeneous patterns that are typically observed in children and young adults. Halo nevi reveal considerable changes of area over time during digital dermoscopic follow-up, albeit their structural patterns remain unchanged. For this reason and because melanoma with halolike depigmentation, despite being rare, additionally exhibits melanoma-specific dermoscopic criteria, the role of digital dermoscopic follow-up in the diagnosis of HN is insignificant.     

Significance of dermoscopic patterns in detecting malignant melanoma on acral volar skin: results of a multicenter study in Japan

OBJECTIVE: To determine diagnostic variables such as sensitivity and specificity of the major dermoscopic patterns observed in melanocytic lesions on acral volar skin, with particular attention to the significance of the parallel ridge pattern and irregular diffuse pigmentation in detecting acral melanoma. DESIGN: Multicenter, retrospective study. SETTING: University hospitals in Japan. PATIENTS: Patients with melanocytic lesions on acral volar skin. A total of 712 melanocytic lesions (103 malignant melanomas, including 36 in situ lesions, and 609 melanocytic nevi) were consecutively collected from the files of 3 hospitals. Diagnoses of all the lesions had been determined histopathologically. INTERVENTIONS: Dermoscopic examination. MAIN OUTCOME MEASURES: The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the major dermoscopic patterns seen in benign and malignant melanocytic lesions on acral volar skin. RESULTS: The parallel ridge pattern and irregular diffuse pigmentation showed extremely high specificity (99.0% and 96.6%, respectively) and very high negative predictive value (97.7% and 97.5%, respectively) in malignant melanoma. For melanoma in situ, the positive predictive value and diagnostic accuracy of the parallel ridge pattern were significantly higher than those of irregular diffuse pigmentation (P = .009 and P = .006, respectively). In melanocytic nevi, the specificity and positive predictive value of the parallel furrow pattern and/or the latticelike pattern were found to be very high (93.2% and 98.3%, respectively). CONCLUSIONS: Dermoscopy is immensely helpful in differentiating malignant melanomas from melanocytic nevi on acral volar skin. Moreover, the parallel ridge pattern aids in detecting acral melanomas in early, curable stages.     

Spitz nevus: follow-up study of 8 cases of childhood starburst type and proposal for management

Spitz nevus is an uncommon, benign melanocytic neoplasm that shares many clinical and histological features with melanoma. It presents clinical ambiguity that makes the diagnosis and management of the patient difficult. We present our experience in the management of Spitz nevus by rigorous dermoscopic long-term follow-up of 8 Spitz nevi in patients younger than 12 years. Dermoscopic images, acquired every 6 months, show evolution and modifications of these lesions. The aim of this paper is to better understand the long-term modifications of nevi with starburst pattern to avoid surgical excision of these lesions in the pediatric age group.     

Dermoscopic changes in melanocytic naevi in children during digital follow-up

The aim of this study was to investigate the dermoscopic changes in acquired melanocytic naevi in a large paediatric population over an interval of several years. Images of 717 melanocytic naevi were obtained from 160 consecutive patients. Dermoscopic pigment pattern changes were observed in one of two lesions after a follow-up of one year, in 34 of 295 lesions (11.5%) after 2 years, in 40 of 190 lesions (21.1%) after 3 years, in 40 of 141 lesions (28.4%) after 4 years, in 5 of 37 lesions (13.5%) after 5 years, in 12 of 31 lesions (38.8%) after 6 years, and in 7 of 21 lesions (33.3%) after 7 years. Dermoscopic changes were detected in 25.3% of the lesions in patients aged 3-6 years, in 21% of the lesions in patients aged 7-12 years, and in 15.5% of the lesions in patients over 13 years. Main pattern changes consisted of transition from globular to globular-reticular (35 naevi), from globular to reticular (14 naevi) and from globular-reticular to reticular (24 naevi). These results are consistent with the view that melanocytic naevi generally undergo a characteristic transition from a globular pattern to a reticular pattern. Most of the changes are observed in the 3-6 years age group when hormonal and/or environmental factors are not thought to play a role in pattern alterations.