Paediatric melanoma

Dermatologic Review in Pediatric Vascular Lesions

Vascular anomalies (VAs) can be present in any organ; however, the skin being the largest one, it is there where many of them are evident; some are visible at birth, others develop throughout life. Pediatric dermatologists are specially trained to distinguish VAs from their mimickers, which require different treatments and may harbor distinct prognoses. We resume the diagnostic and therapeutic tasks of pediatric dermatologist at our vascular anomaly clinics, as well as the differential diagnoses of mimickers of VAs.

Pediatric Atypical Melanocytic Proliferations: Single-Site Retrospective Cohort Assessment of Treatment and Long-Term Follow-Up

Atypical and malignant cutaneous tumors are understudied in the pediatric population, with limited data on long-term follow-up. This study examines pediatric (0-18 years) atypical melanocytic proliferations over a twenty-year period (January 2002-December2022) using the EPIC SlicerDicer at our institution. Over a twenty-year period, there were 55 cases of pediatric melanoma (53 patients). The median follow-up time was 8 years, 11 months. A proportion of 96% were treated with wide local excision (WLE), and 47% had a sentinel lymph node biopsy (SLNB) (35% positive rate). There were 101 atypical Spitz tumor cases (85% atypical Spitz tumors, 15% Spitz melanoma), with a median follow-up duration of 9 years. A proportion of 77% were treated with WLE (with one patient dying of metastatic disease). There were 10 cases of atypical melanocytic proliferations not otherwise specified, including 5 pigmented epithelioid melanocytomas (PEM), 4 deep-penetrating nevi, and 1 atypical cellular blue nevus. This study adds to the growing body of knowledge on pediatric atypical cutaneous melanocytic proliferations, aligning with many described characteristics such as disease location and overall survival rates, with distinct exceptions (higher melanoma positive SLNB rate, lower atypical Spitz tumor WLE rate, and a case of fatal metastatic atypical Spitz tumor).

Increased incidence of melanoma in children and adolescents in Finland in 1990-2014: nationwide re-evaluation of histopathological characteristics

BACKGROUND

Changes in the incidence of melanoma in children and adolescents have been reported in Europe and in the USA in the recent decades.

AIMS

The aim of this study was to examine the incidence of paediatric and adolescent melanomas in Finland in 1990-2014, and the associated clinical and histopathological characteristics to reveal temporal trends, such as changes in diagnostic sensitivity of Spitzoid melanomas.

METHODS

Information on 122 patients diagnosed with cutaneous melanoma at 0-19 years of age in Finland in 1990-2014 were retrieved from the Finnish Cancer Registry. 73 primary melanoma archival samples were re-evaluated by two dermatopathologists to allow comparability over time.

RESULTS

A 5.6% annual increase was observed in the incidence of melanoma among children and adolescents during the study period. Fifty-six tumours were confirmed as malignant melanomas in the re-evaluation. After correction for tumour misclassification in the Cancer Registry, the age-adjusted annual incidence was estimated to have increased from 1.4/1 000 000 in 1990-1994 to 5.8/1 000 000 in 2010-2014. The change in incidence was most prominent among adolescents and in Spitzoid melanoma subtype. Melanomas diagnosed 1990-2002 and 2003-2014 did not differ in terms of their clinicopathological characteristics or prognosis (hazard ratio for melanoma-related death 1.53, 95% CI 0.30 to 7.88). Spitzoid melanomas were diagnosed at a younger age, were of higher stage and had higher Clark level than other melanomas, yet the hazard ratio for death was 0.52 (95% CI 0.10 to 2.58) for Spitzoid versus other melanomas.

CONCLUSIONS

The incidence of cutaneous melanoma has clearly increased among the young in Finland, especially among adolescents. No evidence for overdiagnosis of Spitzoid melanomas as the underlying cause of the increased incidence was observed.Key messageA nationwide retrospective re-evaluation of the cutaneous melanomas recorded in the Finnish Cancer Registry among patients aged 0-19 years in Finland in 1990-2014 revealed an approximately 4-fold increase in the incidence. The increase in the incidence was most prominent among adolescents and in the Spitzoid melanoma subtype. Our results contrast those reported in other countries, where the incidence of melanoma among adolescents has declined.

Investigation on the Awareness and Behavior of Primary School Students on Sunscreen Use in Beijing

Objective

This study aims to understand primary school students’ behavior and awareness of sun exposure and sunscreen in Beijing, China.

Methods

A questionnaire survey was conducted of 232 students in grades 4–6 at a public primary school in Beijing, including 129 boys (55.6%) and 103 girls (44.4%). The contents of the questionnaire included awareness about ultraviolet rays, sun exposure, sunscreen habits, and the understanding and use of sunscreen.

Results

The majority of the subjects (75.0%) said they had never been sunburned, and 26.3% had never been tanned. Only 7.3% of the primary school students had a comprehensive and correct understanding that sunlight will burn, cause cancer, tan, and age the skin. Sunscreen (47.8%), sunshades (47.4%), sun hats (44.4%), avoiding going out at noon (37.5%), and sunglasses (30.2%) were the most frequently used sunscreen means. Furthermore, 47.8% of primary school students used topical sunscreen for light protection, higher than other measures. The proportion of girls using sunscreen at least once a day was more than boys.

Conclusion

Primary school students in Beijing, China, do not have a comprehensive understanding of ultraviolet rays, and there are deficiencies in protective behavior. Their awareness and use of sunscreen need to be improved.

Differences in individual and environmental factors between cutaneous melanoma and atypical Spitz tumour in children and adolescents

It is not known if children and adolescents with atypical Spitz tumour and cutaneous melanoma differ in terms of etiological factors. The aim of this study was to explain differences in individual and environmental factors between cutaneous melanoma and atypical Spitz tumour. In the context of a study on melanocytic lesions, all subjects aged under 20 years with either cutaneous melanoma or atypical Spitz tumour were included (N = 105). Information on socio-demographic characteristics, individual and environmental factors were collected for both mother and child. The Fisher's exact test and the Mann-Whitney U test were used for categorical variables and continuous variables respectively. A multivariate logistic model was used to explain differences in outcome by differences in explanatory variables. In comparison to patients with cutaneous melanoma, patients with atypical Spitz tumour had less freckles (p = 0.020), lower number of common nevi (p = 0.002), and lower body mass index (p = 0.001) and experienced less sunburns episodes (p = 0.008). However, in the multivariate analysis, only a low number of common nevi remained statistically significant. Children and adolescents with cutaneous melanoma have a high number of nevi in comparison to the same-age group with atypical Spitz tumour.Conclusion: The results of this study suggest that the only difference in individual and environmental risk factors between cutaneous melanoma and atypical Spitz tumour in children and adolescents is the number of nevi. What is Known: •Atypical Spitz tumours and cutaneous melanoma in children and adolescents are clinically similar, but compared with melanoma, they have a good overall prognosis. •Risk factors for cutaneous melanoma in children and adolescents are similar to the ones found in adults in the literature What is New: •Differences in individual and environmental risk factors for atypical Spitz tumour in children and adolescents are described for the first time in this study. •Individual and environmental factors for atypical Spitz tumour in children and adolescents are comparable to cutaneous melanoma, except for the presence of low number of nevi.

Melanoma in children and adolescents: analysis of susceptibility genes in 123 Italian patients

BACKGROUND

A polygenic inheritance involving high, medium and low penetrance genes has been suggested for melanoma susceptibility in adults, but genetic information is scarce for paediatric patients.

OBJECTIVE

We aim to analyse the major high and intermediate melanoma risk genes, CDKN2A, CDK4, POT1, MITF and MC1R, in a large multicentre cohort of Italian children and adolescents in order to explore the genetic context of paediatric melanoma and to reveal potential differences in heritability between children and adolescents.

METHODS

One-hundred-twenty-three patients (<21 years) from nine Italian centres were analysed for the CDKN2A, CDK4, POT1, MITF, and MC1R melanoma predisposing genes. The rate of gene variants was compared between sporadic, familial and multiple melanoma patients and between children and adolescents, and their association with clinico-pathological characteristics was evaluated.

RESULTS

Most patients carried MC1R variants (67%), while CDKN2A pathogenic variants were found in 9% of the cases, the MITF E318K in 2% of patients and none carried CDK4 or the POT1 S270N pathogenic variant. Sporadic melanoma patients significantly differed from familial and multiple cases for the young age at diagnosis, infrequent red hair colour, low number of nevi, low frequency of CDKN2A pathogenic variants and of the MC1R R160W variant. Melanoma in children (≤12 years) had more frequently spitzoid histotype, were located on the head/neck and upper limbs and had higher Breslow thickness. The MC1R V92M variant was more common in children than in adolescents. CDKN2A common polymorphisms and MC1R variants were associated with a high number of nevi.

CONCLUSION

Our results confirm the scarce involvement of the major high-risk susceptibility genes in paediatric melanoma and suggest the implication of MC1R gene variants especially in the children population.

Pseudomalignancies in Children: Histological Clues, and Pitfalls to Be Avoided

The term “pseudomalignancy” covers a large, heterogenous group of diseases characterized by a benign cellular proliferation, hyperplasia, or infiltrate that resembles a true malignancy clinically or histologically. Here, we (i) provide a non-exhaustive review of several inflammatory skin diseases and benign skin proliferations that can mimic a malignant neoplasm in children, (ii) give pathologists some helpful clues to guide their diagnosis, and (iii) highlight pitfalls to be avoided. The observation of clinical–pathological correlations is often important in this situation and can sometimes be the only means (along with careful monitoring of the disease’s clinical course) of reaching a firm diagnosis.

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).

Pediatric vulvar malignancies: rare but important to know

Malignancies of the vulva in the pediatric population are exceptionally rare, which makes it difficult to gain any insight into their clinicopathologic profile. In this review, we summarize all published cases of a vulva malignancy in pediatric patients (≤21 years) reported in the English language literature for the 50-year period between 1970 and 2020. We estimate that less than 100 malignancies have been reported in total, approximately 50% of which were rhabdomyosarcomas. Invasive squamous cell carcinomas, yolk sac tumors, Ewing sarcoma/primitive neuroectodermal tumors (ES/PNET) and melanomas each represented approximately 10% of reported cases. For rhabdomyosarcoma, the alveolar and embryonal subtypes were reported with equal frequency, with both representing 70% of cases combined. The average patient age was 9.8 years. 48% and 35% were Intergroup Rhabdomyosarcoma Study clinical groupings I and III respectively. Managements were generally multimodal, and overall outcomes for the group were favorable. For invasive squamous cell carcinoma, the patients were all in their teenage years, with an average age at diagnosis of 15.2 years. A small subset of cases were associated with human papillomavirus and immunosuppression, and it is possible that immunosuppression has a role in vulvar squamous carcinogenesis in this population. One case was associated with lichen sclerosus. The patients with yolk sac tumors ranged in age from less than 1 year to 20 years (mean 12) and 67% of cases were stage I at presentation. An insufficient number of cases have been reported to define their prognosis, although some cases were notably aggressive. The few reported cases of melanoma are distinctive only because they were all associated with lichen sclerosus, suggestive of some role for the latter in their pathogenesis. The average age of patients reported with ES/PNET was 15 years (range 3.3 to 20). At least half of the reported cases were advanced stage at presentation, and patient outcomes were notably poor: 62.5% were dead of disease at follow-up. Pediatric vulvar malignancies are rare and are mostly comprised of 5 entities. Their accurate pathologic classification is necessary to facilitate optimal management.

Imaging of pediatric cutaneous melanoma

Melanoma accounts for 7% of all cancers in adolescents ages 15-19 years but is an unexpected malignancy in younger children. The prevalence of malignant melanoma is very rare in children ages 1-4 years, but certain non-modifiable risk factors such as xeroderma pigmentosum, congenital melanocytic nevus syndrome and other inherited traits increase the risk for its development in these young children. Recent genomic studies have identified characteristics of pediatric melanoma that differ from conventional melanoma seen in adults. In this review the authors inform on the types of melanoma seen in children and adolescents, discuss similarities and differences in melanoma between children and adults, and discuss the role of imaging in the care of these children.

Current state of melanoma diagnosis and treatment

Melanoma is the deadliest form of skin cancer. In the early stages, melanoma can be treated successfully with surgery alone and survival rates are high, but after metastasis survival rates drop significantly. Therefore, early and correct diagnosis is key for ensuring patients have the best possible prognosis. Melanoma misdiagnosis accounts for more pathology and dermatology malpractice claims than any cancer other than breast cancer, as an early misdiagnosis can significantly reduce a patient’s chances of survival. As far as treatment for metastatic melanoma goes, there have been several new drugs developed over the last 10 years that have greatly improved the prognosis of patients with metastatic melanoma, however, a majority of patients do not show a lasting response to these treatments. Thus, new biomarkers and drug targets are needed to improve the accuracy of melanoma diagnosis and treatment. This article will discuss the major advancements of melanoma diagnosis and treatment from antiquity to the present day.

cAMP-mediated regulation of melanocyte genomic instability: A melanoma-preventive strategy

Malignant melanoma of the skin is the leading cause of death from skin cancer and ranks fifth in cancer incidence among all cancers in the United States. While melanoma mortality has remained steady for the past several decades, melanoma incidence has been increasing, particularly among fair-skinned individuals. According to the American Cancer Society, nearly 10,000 people in the United States will die from melanoma this year. Individuals with dark skin complexion are protected damage generated by UV-light due to the high content of UV-blocking melanin pigment in their epidermis as well as better capacity for melanocytes to cope with UV damage. There is now ample evidence that suggests that the melanocortin 1 receptor (MC1R) is a major melanoma risk factor. Inherited loss-of-function mutations in MC1R are common in melanoma-prone persons, correlating with a less melanized skin complexion and poorer recovery from mutagenic photodamage. We and others are interested in the MC1R signaling pathway in melanocytes, its mechanisms of enhancing genomic stability and pharmacologic opportunities to reduce melanoma risk based on those insights. In this chapter, we review melanoma risk factors, the MC1R signaling pathway, and the relationship between MC1R signaling and DNA repair.

Pediatric Melanoma and Drug Development

Importance-Pediatric melanoma occurs, albeit rarely. Should patients be treated by today's medical standards, or be subjected to medically unnecessary clinical studies? Observations-We identified international, industry-sponsored pediatric melanoma studies triggered by regulatory demands in www.clinicaltrials.gov and further pediatric melanoma studies demanded by European Union pediatric investigation plans. We retrieved related regulatory documents from the internet. We analyzed these studies for rationale and medical beneficence on the basis of physiology, pediatric clinical pharmacology and rationale. Regulatory authorities define children by chronological age, not physiologically. Newborns' organs are immature but they develop and mature rapidly. Separate proof of efficacy in underage patients is justified formally/regulatorily but lacks medical sense. Children-especially post-puberty-and adults vis-a-vis medications are physiologically very similar. Two adolescent melanoma studies were terminated in 2016 because of waning recruitment, while five studies in pediatric melanoma and other solid tumors, triggered by European Union pediatric investigation plans, continue recruiting worldwide. Conclusions and Relevance-Regulatory-demanded pediatric melanoma studies are medically superfluous. Melanoma patients of all ages should be treated with effective combination treatment. Babies need special attention. Children need dose-finding and pharmacokinetic studies but adolescents metabolize and respond to drugs similarly to adults. Institutional Review Boards/ethics committees should suspend ongoing questionable pediatric melanoma studies and reject newly submitted questionable studies.