Common and not so Common Melanocytic Lesions in Children and Adolescents

Giant Congenital Melanocytic Nevus with Congenital Neurofibroma: A Case Report

BACKGROUND

Giant congenital melanocytic nevus (GCMN) is characterized by its large size and potential for transformation into melanoma. It can be associated with other neural cristopathies, including neurofibroma, however, it has not previously been described with a congenital neurofibroma.

CASE REPORT

A newborn girl presented with a large congenital neurofibroma arising in a bathing trunk type of giant congenital melanocytic nevus.

CONCLUSION

Congenital neurofibromas can be associated with (or a component of) a GCMN.

Ungual Spitz Nevus: Description of Dermoscopic Data

INTRODUCTION

Spitz nevus is an uncommon, benign melanocytic proliferation that primarily appears on face, trunk or lower extremities of children. This lesion may share clinical and microscopical characteristics with melanoma, making it a diagnostic and management challenge.

CASE REPORT

A 13-year old male presented with an asymptomatic chronic dermatosis located on the third left-hand nail. Cutaneous examination revealed a homogeneous dark brown melanonychia which extended up to the cuticle. Upon dermoscopy, longitudinal bands measuring less than 3 mm wide of heterogeneous colors ranging from light to dark brown, and positive Hutchinson's sign were observed.

DISCUSSION/CONCLUSION

We report the second case of a Spitz nevus ungually localized which strongly resembled an ungual melanoma with a positive Hutchinson's sign upon dermoscopy. Describing the infrequent presentation and location of the Spitz nevus poses an opportunity to establish diagnostic and management criteria in the near future.

Molecular Markers of Pediatric Solid Tumors—Diagnosis, Optimizing Treatments, and Determining Susceptibility: Current State and Future Directions

Advances in molecular technologies, from genomics and transcriptomics to epigenetics, are providing unprecedented insight into the molecular landscape of pediatric tumors. Multi-omics approaches provide an opportunity to identify a wide spectrum of molecular alterations that account for the initiation of the neoplastic process in children, response to treatment and disease progression. The detection of molecular markers is crucial to assist clinicians in accurate tumor diagnosis, risk stratification, disease subtyping, prediction of treatment response, and surveillance, allowing also for personalized cancer management. This review summarizes the most recent developments in genomics research and their relevance to the field of pediatric oncology with the aim of generating an overview of the most important, from the clinical perspective, molecular markers for pediatric solid tumors. We present an overview of the molecular markers selected based on therapeutic protocols, guidelines from international committees and scientific societies, and published data.

What's new in pediatric melanoma and Spitz tumors? Pretty much everything

LAY SUMMARY

Pathologists sometimes have great difficulty in determining whether a mole biopsied from the skin of a child is benign or malignant. New molecular technologies have helped pathologists to identify pediatric melanomas, but there are still some atypical moles that cannot be definitively classified as benign or malignant. With further research, it is hoped that the number of these atypical tumors can be decreased and that the treatment for all children with moles and melanoma can be improved.

Melanotic Neuroectodermal Tumor of Infancy at Skull: Rare and Rapid-Growing Tumor but Histologically Benign

INTRODUCTION

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare and rapid-growing tumor. However, a neurosurgeon should not overlook this entity when differential diagnosing rapid-growing skull tumor because its histology nature is just benign, and the prognosis is much better than other malignant tumors.

CASE PRESENTATION

We reported the case of a 5-month old male presenting with progressive rapid-growing skull tumor which became 10 cm in diameter in only 5 months compared to the normal head circumference at birth. At first, we thought of malignant skull tumor and performed only biopsy to establish diagnosis. But, when the pathology revealed benign MNTI, we performed preoperative tumor embolization and then radical surgery. Good result was observed.

DISCUSSION

Skull MNTI is the second most common location after the maxilla. Even advanced imaging nowadays cannot distinguish MNTI from other malignant tumors definitely. Urgent biopsy is recommended to establish diagnosis of this benign tumor first. Preoperative angiography with tumor embolization is recommended when feasible, followed by craniotomy with radical resection.

Neurocutaneous melanocytosis (melanosis)

Neurocutaneous melanosis (NCM; MIM # 249400; ORPHA: 2481], first reported by the Bohemian pathologist Rokitansky in 1861, and now more precisely defined as neurocutaneous melanocytosis, is a rare, congenital syndrome characterised by the association of (1) congenital melanocytic nevi (CMN) of the skin with overlying hypertrichosis, presenting as (a) large (LCMN) or giant and/or multiple (MCMN) melanocytic lesions (or both; sometimes associated with smaller "satellite" nevi) or (b) as proliferative melanocytic nodules; and (2) melanocytosis (with infiltration) of the brain parenchyma and/or leptomeninges. CMN of the skin and leptomeningeal/nervous system infiltration are usually benign, more rarely may progress to melanoma or non-malignant melanosis of the brain. Approximately 12% of individuals with LCMN will develop NCM: wide extension and/or dorsal axial distribution of LCMN increases the risk of NCM. The CMN are recognised at birth and are distributed over the skin according to 6 or more patterns (6B patterns) in line with the archetypical patterns of distribution of mosaic skin disorders. Neurological manifestations can appear acutely in infancy, or more frequently later in childhood or adult life, and include signs/symptoms of intracranial hypertension, seizures/epilepsy, cranial nerve palsies, motor/sensory deficits, cognitive/behavioural abnormalities, sleep cycle anomalies, and eventually neurological deterioration. NMC patients may be symptomatic or asymptomatic, with or without evidence of the typical nervous system changes at MRI. Associated brain and spinal cord malformations include the Dandy-Walker malformation (DWM) complex, hemimegalencephaly, cortical dysplasia, arachnoid cysts, Chiari I and II malformations, syringomyelia, meningoceles, occult spinal dysraphism, and CNS lipoma/lipomatosis. There is no systemic involvement, or only rarely. Pathogenically, single postzygotic mutations in the NRAS (neuroblastoma RAS viral oncogene homologue; MIM # 164790; at 1p13.2) proto-oncogene explain the occurrence of single/multiple CMNs and melanocytic and non-melanocytic nervous system lesions in NCM: these disrupt the RAS/ERK/mTOR/PI3K/akt pathways. Diagnostic/surveillance work-ups require physical examination, ophthalmoscopy, brain/spinal cord magnetic resonance imaging (MRI) and angiography (MRA), positron emission tomography (PET), and video-EEG and IQ testing. Treatment strategies include laser therapy, chemical peeling, dermabrasion, and surgical removal/grafting for CMNs and shunt surgery and surgical removal/chemo/radiotherapy for CNS lesions. Biologically targeted therapies tailored (a) BRAF/MEK in NCM mice (MEK162) and GCMN (trametinib); (b) PI3K/mTOR (omipalisib/GSK2126458) in NMC cells; (c) RAS/MEK (vemurafenib and trametinib) in LCMNs cells; or created experimental NMC cells (YP-MEL).

Head and Neck Melanoma Incidence Trends in the Pediatric, Adolescent, and Young Adult Population of the United States and Canada, 1995-2014

Importance

Melanoma is one of the most common cancers worldwide, typically diagnosed in older adults. There is an increasing incidence in the younger population (age ≤40 years) in America. In addition, approximately 1 in 5 cases of melanoma affect the head and neck. However, there are limited data on the incidence of head and neck melanoma in the pediatric, adolescent, and young adult population in North America (United States and Canada).

Objective

To assess 20-year demographic and incidence changes associated with head and neck melanoma in the pediatric, adolescent, and young adult population in North America.

Design, Setting, and Participants

A descriptive analysis of retrospective data on head and neck melanoma from the North American Association of Central Cancer Registries' Cancer in North America public use data set from 1995 to 2014 was conducted. The data set currently includes 93% of the United States and 64% of the Canadian populations. Eligible data were from 12 462 pediatric, adolescent, and young adult patients (aged 0-39 years) with a confirmed diagnosis of melanoma (International Classification of Diseases-Oncology 3 histologic types 8720-8790) in primary head and neck sites: skin of lip, not otherwise specified (C44.0); eyelid (C44.1); external ear (C44.2); skin of other/unspecified parts of face (C44.3); and skin of scalp and neck (C44.4). The study was conducted from January 26 to July 21, 2019.

Main Outcomes and Measures

Log-linear regression was used to estimate annual percentage change in age-adjusted incidence rates (AAIRs) of head and neck melanoma.

Results

Of the 12 462 patients with head and neck melanoma included in the study, 6810 were male (54.6%). The AAIR was 0.51 per 100 000 persons (95% CI, 0.50-0.52 per 100 000 persons). In North America, the incidence of head and neck melanoma increased by 51.1% from 1995 to 2014. The rate was higher in the United States (AAIR, 0.52; 95% CI, 0.51-0.53 per 100 000 person-years) than Canada (AAIR, 0.43; 95% CI, 0.40-0.45 per 100 000 persons). In the United States, the incidence increased 4.68% yearly from 1995 to 2000 and 1.15% yearly from 2000 to 2014. In Canada, the incidence increased 2.18% yearly from 1995 to 2014. Male sex (AAIR, 0.55; 95% CI, 0.54-0.57 per 100 000 persons), older age (AAIR, 0.79; 95% CI, 0.79-0.80 per 100 000 persons), and non-Hispanic white race/ethnicity (AAIR, 0.79; 95% CI, 0.77-0.80 per 100 000 persons) were associated with an increased incidence of head and neck melanoma.

Conclusions and Relevance

The incidence of pediatric, adolescent, and young adult head and neck melanoma in North America appears to have increased by 51.1% in the past 2 decades, with males aged 15 to 39 years the main cohort associated with the increase.

Paediatric melanoma: clinical update, genetic basis, and advances in diagnosis

Paediatric melanoma is rare and challenging to diagnose. The three subtypes are Spitzoid melanoma, melanoma arising in a congenital melanocytic nevus, and conventional (also known as adult-type) melanoma. Spitzoid melanomas have characteristic histopathological and genomic aberrations. Despite frequent involvement of the sentinel lymph nodes, most cases have an uneventful clinical course. Among congenital nevi, the risk of melanoma varies by projected size in adulthood, with the greatest risk in large or giant nevi. The clinical course is generally aggressive and accounts for most melanoma-related deaths in childhood. In conventional melanoma, superficial spreading and nodular melanoma account for most cases, with risk factors and presentation largely similar to adult disease. In this Review, we discuss advances in histological diagnosis using adjunctive molecular assays, and summarise the genetic basis of paediatric melanoma.