Melanocytic Lesions In Children Research Articles

Translated article] Subungual Melanocytic Lesions in Pediatric Patients

The study of subungual melanocytic lesions can present challenges because of the clinical and histologic characteristics of the nail unit and the difficulty of performing nail biopsies and processing specimens. These lesions can be even more challenging in children due to differences in clinical and epidemiological profiles between the adult and pediatric populations. Many of the clinical features of subungual melanocytic lesions that would raise alarm in an adult do not have the same implications in children. Consensus is also lacking on when a nail biopsy is needed to rule out malignancy in the pediatric setting. In view of these considerations and the rarity of subungual melanoma in childhood, the recommended approach in most cases is a watch-and-wait strategy. Subungual melanocytic lesions in children may also show atypical histopathologic features that are not necessarily associated with aggressive behavior. Subungual melanoma is very rare in childhood, with just 21 cases described to date. None of the patients developed visceral metastasis or died as a result and the diagnosis was controversial in many of the cases. Considering the above and the significantly higher frequency and particular characteristics of longitudinal melanonychia with a benign etiology in children, subungual melanocytic lesions should be managed differently in this setting than in adults. In most cases, a watch-and-wait approach is the most appropriate strategy.

Lesiones melanocíticas subungueales en la edad pediátrica

The study of subungual melanocytic lesions can present challenges because of the clinical and histologic characteristics of the nail unit and the difficulty of performing nail biopsies and processing specimens. These lesions can be even more challenging in children due to differences in clinical and epidemiological profiles between the adult and pediatric populations. Many of the clinical features of subungual melanocytic lesions that would raise alarm in an adult do not have the same implications in children. Consensus is also lacking on when a nail biopsy is needed to rule out malignancy in the pediatric setting. In view of these considerations and the rarity of subungual melanoma in childhood, the recommended approach in most cases is a watch-and-wait strategy. Subungual melanocytic lesions in children may also show atypical histopathologic features that are not necessarily associated with aggressive behavior. Subungual melanoma is very rare in childhood, with just 21 cases described to date. None of the patients developed visceral metastasis or died as a result and the diagnosis was controversial in many of the cases. Considering the above and the significantly higher frequency and particular characteristics of longitudinal melanonychia with a benign etiology in children, subungual melanocytic lesions should be managed differently in this setting than in adults. In most cases, a watch-and-wait approach is the most appropriate strategy.

Choroidal melanocytic lesions in children: focal aggregates and melanocytosis

To investigate prevalence and age of onset of choroidal melanocytic lesions (other than nevi) in pediatric patients. The pooled data of participants 6 months to 18 years of age in the Sydney Paediatric Eye Disease Study, the Sydney Myopia Study, and the Sydney Adolescent Vascular Eye Disease Study were reviewed retrospectively to identify children with choroidal melanocytic lesions. The clinical features and prevalence by age were assessed. From the pooled sample of 5,533 unique children, 39 cases of focal melanocytic aggregates and 22 cases of choroidal melanocytosis were identified, with overall prevalence of 0.70% and 0.40%, respectively. There was a statistically significant trend toward increased prevalence with increasing age. Both focal melanocytic aggregates and choroidal melanocytosis tended to be bilateral (100% and 86% respectively), brown in color, and temporally located in all cases. Amelanotic variants were not identified. Focal melanocytic aggregates were small (0.15-0.5 mm), whereas choroidal melanocytosis varied in size (5.0-20 mm). All focal melanocytic aggregates were characteristically located 4-5 mm temporal to the center ofthe fovea and were associated with linear nervelike (11 [28%]) or tortuous vessel like structures (10 [26%]). In this study, pooled data from large population studies revealed morphologic patterns of choroidal melanocytic lesions, other than nevus, that correlate with described clinicalappearance in adults. The association of focal melanocytic aggregates with nervelike structures supports their embryologic origin along the migration path of uveal melanocytes.

Common and not so Common Melanocytic Lesions in Children and Adolescents.

The acquired melanocytic nevus is the most common lesion encountered by pediatric pathologists and dermatopathologists in their daily practice. In most cases, there are few difficulties in histopathologic diagnosis. However, it is the acquired melanocytic lesion known as the Spitz nevus, with its intrinsic atypical features which becomes the challenge since it exists along a histopathologic and biologic continuum from the atypical Spitz tumor to spitzoid melanoma. The frustration with some of these spitzoid lesions is that even the "experts" cannot agree as to the differentiation of one from the other even at the level of molecular genetics. Other melanocytic lesions are discussed including the congenital melanocytic nevus with its proliferative nodule(s) and melanoma as the ultimate complication. Although uncommon, cutaneous melanoma in the first 2 decades is emerging as a clinical problem especially in young women in the second decade of life. These are ultraviolet-associated neoplasms whose histopathologic and prognostic features are identical to the adult experience. Considerable progress has been made over the past 15 to 20 years in our understanding of cutaneous melanocytic lesions, but gaps still exist in the important group of spitzoid lesions. It can also be anticipated that more cutaneous melanomas in children will be seen in the future based upon epidemiologic studies.

Subungual atypical lentiginous melanocytic proliferations in children and adolescents: A clinicopathologic study

Most subungual melanocytic lesions in children are benign, but some are difficult to classify due to prominent lentiginous growth and high-grade cytologic atypia. To characterize the clinicopathologic features of these rare lesions. Subungual atypical lentiginous melanocytic proliferations from patients <20years of age were collected for clinical and histopathologic review. Fluorescence in situ hybridization (FISH) was performed when possible. Eleven patients aged 2-19years had expanding or darkening longitudinal pigmented streak(s) with or without Hutchinson sign. Microscopically, all revealed predominantly single-cell growth, pagetoid scatter, and poor circumscription. Eight (73%) cases showed focal or poor nesting, and 3 (27%) demonstrated confluence. Nuclear enlargement, hyperchromasia, and angulation were present in 8 (73%) cases, 7 (64%) cases, and 6 (55%) cases, respectively. One of 4 cases tested by FISH was positive. Three lesions recurred locally without other adverse outcome. Small sample size and short clinical follow-up. Two cases were examined in partial biopsies only. Some subungual melanocytic lesions in children and adolescents are histologically indistinguishable from adult subungual melanoma in situ. While the biologic potential remains elusive, FISH might aid in risk stratification. Awareness of this rare group of lesions is crucial for facilitating future investigation into its biologic behavior.

Fluorescence in situ hybridization analysis of atypical melanocytic proliferations and melanoma in young patients.

Morphologic heterogeneity among melanocytic proliferations is a common challenge in the diagnosis of melanoma. In particular, atypical melanocytic lesions in children, adolescents, and young adults may be difficult to classify because of significant morphologic overlap with melanoma. Recently a four-probe fluorescence in situ hybridization (FISH) protocol to detect chromosomal abnormalities in chromosomes 6 and 11 has shown promise for improving the classification of melanocytic lesions. We sought to determine the correlation between FISH results, morphology, and clinical outcomes in a series of challenging melanocytic proliferations in young patients. We retrospectively performed the standard four-probe FISH analysis on 21 melanocytic neoplasms from 21 patients younger than 25 years of age (range 5–25 years, mean 14.6 years) from Stanford University Medical Center who were prospectively followed for a median of 51 months (range 1–136 months). The study cohort included patients with 5 confirmed melanomas, 2 melanocytic tumors of uncertain malignant potential (MelTUMPs), 10 morphologically challenging atypical Spitz tumors (ASTs), and 4 typical Spitz nevi. FISH detected chromosomal aberrations in all five melanomas and in one MelTUMP, in which the patient developed subsequent lymph node and distant metastasis. All 10 ASTs, 4 Spitz nevi, and 1 of 2 MelTUMPs were negative for significant gains or losses in chromosomes 6 and 11q. Our findings demonstrated a strong correlation between positive FISH results and the histomorphologic impression of melanoma. This finding was also true for the MelTUMP with poor clinical outcome. Therefore FISH may serve as a helpful adjunct in the classification of controversial melanocytic tumors in young patients.

Retrospective analysis of melanocytic lesions in children at the National Cancer Institute-RJ.

Skin cancer is the most common neoplasm in Brazil. Melanoma accounts for 4% of these neoplasms. Although childhood melanoma is rare, there is evidence that its incidence is increasing, placing it among the most important public health problems for the future. This work sought to conduct a retrospective review of cases of suspected melanocytic skin lesions in children, their diagnosis and management, and evaluate the sentinel lymph node biopsy method in some cases of cutaneous melanoma.

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.

Problematic Lesions in Children

Melanoma in childhood is rare, and appears more commonly either in association with a preexisting (congenital) nevus, or with spitzoid features than de novo. Thus, problematic melanocytic lesions in children are essentially represented by congenital nevi and Spitz nevi that can be regarded as melanoma precursors and melanoma simulators, respectively. As a consequence, clinical and dermoscopic features of melanoma in children differ from those in an adult population. Herein we describe common clinical and dermoscopic features of problematic lesions in children, focusing on congenital and Spitz/Reed nevi, and including other problematic lesions, such as atypical, blue, acral, and scalp nevi.

Analysis of clinical and dermoscopic features in melanocytic lesions with special emphasis on problematic lesions in children

Most melanocytic lesions in children are considered ‘nonproblematic’ and are managed conservatively because of their invariable benignity. Congenital melanocytic nevi (CMN) and Spitz nevi are the most problematic pigmented lesions in childhood. Regarding CMN, the biggest risk of melanoma development occurs with increased nevus size, being particularly high in giant CMN, in children younger than 10 years. On the other hand, awareness should be related to new, rapidly growing lesions (the clinical hallmark of Spitz/Reed nevi and melanoma). The aim of this review is to present clinical and dermoscopic features of a large spectrum of pediatric melanocytic lesions with special attention to problematic lesions that may occur in childhood.

Excised melanocytic lesions in children and adolescents - a 10-year survey

Early recognition and prompt excision is to date the only available strategy for reducing mortality from melanoma. Little is known about the accuracy of melanoma detection in children and adolescents. To assess the accuracy of melanoma detection in a paediatric population. From the Department of Dermatology, Medical University of Graz, Austria, we reviewed the dermatopathology reports of naevi and melanomas excised in patients younger than 20 years over a 10-year period (1998-2007). Patients were subdivided into four age groups: 0-4, 5-9, 10-14 and 15-19 years. Accuracy in melanoma detection was tested using the number needed to excise (NNE) value that is obtained by dividing the total number of excised lesions by the number of melanomas. A total of 22564 lesions were reviewed, disclosing 22526 naevi and 38 melanomas, for an overall NNE value of 593.8. Five melanomas were excised in children aged 10-14 years (NNE 1141) and 33 in children aged 15-19 years (NNE 479.8), whereas no melanomas were found among 1026 lesions excised in children younger than 10 years. In children aged 0-4 years, congenital and Spitz/Reed naevi accounted for 34.5% and 20% of lesions, respectively. These percentages decreased progressively when moving to older age groups (P<0.0001). In contrast, the percentage of dermal and compound naevi rose in direct proportion with age, being 3.4% and 20.7%, respectively, in the youngest age group, and 36.7% and 31.9%, respectively, among the oldest patients (P<0.0001). The overall NNE value in paediatric patients over the 10-year study period was 593.8, meaning that about 594 lesions were excised to find one melanoma. This value is 20 times higher than the rates found in adult patients.

Clinical and dermoscopic features of 88 scalp naevi in 39 children

Paediatric scalp naevi may represent a source of anxiety for practitioners and parents, as the clinical and dermoscopic features of typical naevi have yet to be defined. Prompted by concern about the large size, irregular borders and colour variation of scalp naevi, clinicians and parents may request unnecessary excision of these naevi. To establish the typical clinical and dermoscopic patterns of scalp naevi in children younger than 18 years old to help optimize clinical care and management. Scalp naevi were imaged with a camera (Canon Rebel, XSi; Canon, Tokyo, Japan) and dermoscopic attachment (Dermlite Foto, 30 mm lens; 3Gen, San Juan Capistrano, CA, U.S.A.) to the camera. The clinical and dermoscopic images were reviewed and analysed. Both acquired and congenital scalp naevi were included but were not further differentiated from each other. We obtained clinical and dermoscopic images of 88 scalp naevi in 39 white children. Two subjects had received chronic immunosuppressive medication. Nineteen children had a family history of melanoma. Boys (18/39 subjects, 46%) possessed 68% (60 naevi) of scalp naevi imaged. Younger (< 10 years old) subjects (24/39 subjects, 62%) possessed 42% (37 naevi) of scalp naevi. The main clinical patterns included eclipse (n=18), cockade (n = 3), solid brown (n=42) and solid pink (n=25) naevi. Solid-coloured naevi showed the following dermoscopic patterns: globular (57%), complex (reticular-globular) (27%), reticular (9%), homogeneous (6%) and fibrillar (1%). The majority of naevi had a unifying feature - perifollicular hypopigmentation, which caused the appearance of scalloped, irregular borders if occurring on the periphery, or variegation in pigmentation, if occurring within the naevi. Older subjects and boys tend to harbour a larger proportion of scalp naevi. The main clinical patterns include solid-coloured and eclipse naevi. The most common dermoscopic pattern of scalp naevi is the globular pattern. Perifollicular hypopigmentation is a hallmark feature of signature scalp naevi. Dermoscopy is a noninvasive tool in the evaluation of cutaneous melanocytic lesions in children and may decrease the number of unnecessary excisions.

Problematic melanocytic lesions in children

Melanocytic lesions in children are almost invariably benign and, consequently, their clinical management in most cases should be easy. There are, however, two problematic issues: one is the differential diagnosis between melanoma and Spitz nevus; the second is related to giant congenital melanocytic nevus. This is the most important risk factor for melanoma among children younger than 12 years of age, although less than 1% of children with congenital nevi will develop melanoma. Given that pediatric melanoma is extremely rare, most physicians will probably never be confronted with this malignancy. It appears that awareness related to the two previously mentioned problematic lesions is of greater utility, which would suggest immediate action in cases of new, rapidly growing lesions (the clinical hallmark of Spitz nevus) or in cases of congenital nevi with recent change in size, color and/or shape. In this review, we describe the most common clinical and dermoscopic features of a large spectrum of pediatric...

Diagnostically Challenging Melanocytic Lesions in Children

Cultaneous melanocytic lesions are commonly biopsied in pediatric dermatology clinics. Most are diagnosed without difficulty. In this article, we present three diagnostically challenging cases from our institution: cellular blue nevus, a congenital pattern nevus with proliferative nodules, and an atypical Spitzoid tumor.

Problematic melanocytic lesions in children

Problematic melanocytic lesions in children

Cutaneous melanoma in childhood and adolescence: An analysis of 36 patients

Analysis of data of 6931 patients with cutaneous melanoma seen at the Department of Dermatology and Allergology at the Ludwig-Maximilians-University of Munich between 1977 and 1998 identified 36 patients in whom cutaneous melanomas developed during childhood or adolescence (age <18 years). Clinical courses of all patients and histopathologic characteristics of the lesions were reviewed. Seventeen patients were boys and 19 patients were girls. The median ages of the boys and girls were 15 and 16 years, respectively (range, 2-17 years). Thirty-one patients presented with nonmetastatic primary melanomas and 5 patients presented with metastatic melanoma. Forty-seven percent of the primary lesions were associated with a nevus (22% with congenital nevi and 25% with acquired nevi). Tumor thickness ranged from 0.24 to 7.0 mm, with a median of 1.29 mm (mean, 1.67 mm). All patients with primary melanomas received surgical therapy; patients with metastatic disease received chemotherapy, radiation therapy, or both. Relative 5-year survival was 87.5% for the group of patients younger than 18 years. Similar to experience in adult patients, survival strongly correlated with tumor thickness and clinical stage at the time of diagnosis. The data emphasize that a high index of suspicion for cutaneous melanoma is needed by clinicians assessing melanocytic lesions in children and adolescents for early diagnosis. Reduction of the melanoma mortality rate in children and adolescents will be achieved through identification of patients at increased risk. (J Am Acad Dermatol 2002;46:874-9.)

Histopathological features of acral melanocytic nevi in children: study of 21 cases.

Benign melanocytic lesions in children may give cause for some concern histologically. This is because they represent a specific entity, or they reflect the state of evolution of the lesion or the anatomical location. This latter phenomenon has been poorly documented in children. In this study, we address the problem of atypical features frequently seen in benign nevi from acral sites in a group of patients aged 18 years or less. Twenty-one cases (12 female, 9 male) were identified from the Department of Pathology files during the years 1975-1988. All were Caucasian. Histological examination revealed that 6 cases were congenital and 15 were acquired; of these, 19 cases (90%) had a junctional component and all of these exhibited architecture atypia in the form of either lentiginous proliferation (84%) or confluence of junctional nests (84%). Forty-two percent (8/19) showed a mixture of both. Thirty-seven percent (7/19) exhibited transepidermal elimination of melanocytic nests, with 13/19 (68%) showing single cell infiltration of the epidermis. Atypical size, shape, and location of the junctional nests were present in 10/19 cases (53%). Within this group there appears to be no relationship between the age of the patient and the degree of architectural atypia. Mild cytological atypia was common. This report stresses the importance of anatomic subsite in the assessment of melanocytic lesions in children as well as in adults.