The unique clinical characteristics of melanoma diagnosed in children

Melanoma in Pediatric and Young Adult Patients

PURPOSE OF REVIEW

Melanoma in younger individuals has different clinical presentations, histologic characteristics and prognosis from older patients. This review summarizes key differences and important new insights into pediatric and young adult melanoma, as well as recent evolutions in treatment.

RECENT FINDINGS

Molecular techniques have improved the classification of melanocytic neoplasms, and are especially useful in the workup of the diagnostically challenging lesions frequent in this age group. Molecular evaluation highlights differences between melanoma and atypical lesions with Spitz-like morphology, and should routinely be incorporated for diagnosing and classifying Spitzoid melanocytic to guide prognostication and treatment. Once diagnosed, the management of bona fide melanoma in children and young adults is largely similar to older patients, while the optimal management of lesions such as atypical Spitz tumors remains uncertain. Increased awareness of the presentation and diagnostic characteristics of melanoma in young individuals will allow earlier detection, and improved diagnostic techniques will allow optimum management without over- or under-treatment.

Risk factors and outcomes of melanoma in children and adolescents: A retrospective multicenter study

BACKGROUND

Pediatric melanoma presents with distinct clinical features compared to adult disease.

OBJECTIVE

Characterize risk factors and negative outcomes in pediatric melanoma.

METHODS

Multicenter retrospective study of patients under 20 years diagnosed with melanoma between January 1, 1995 and June 30, 2015 from 11 academic medical centers.

RESULTS

Melanoma was diagnosed in 317 patients, 73% of whom were diagnosed in adolescence (age ≥11). Spitzoid (31%) and superficial spreading (26%) subtypes were most common and 11% of cases arose from congenital nevi. Sentinel lymph node biopsy was performed in 68% of cases and positive in 46%. Fatality was observed in 7% of cases. Adolescent patients with melanoma were more likely to have family history of melanoma (P = .046) compared to controls.

LIMITATIONS

Retrospective nature, cohort size, control selection, and potential referral bias.

CONCLUSION

Pediatric melanoma has diverse clinical presentations. Better understanding of these cases and outcomes may facilitate improved risk stratification of pediatric melanoma.

Melanoma in children: A systematic review and individual patient meta-analysis

The current evidence on paediatric melanoma is heterogeneous, especially regarding the prognosis of different histological subtypes. We sought to systematically review the evidence on paediatric melanoma, highlighting the major sources of heterogeneity and focusing on available data on single patients. A systematic search was performed from 1948 to 25 January 2021. Only studies reporting at least one case of cutaneous melanoma in patients aged ≤18 years were included. Unknown primary and uncertain malignant melanomas were excluded. Three couples of authors independently performed title/abstract screening and two different authors reviewed all the relevant full texts. The selected articles were manually cross-checked for overlapping data for qualitative synthesis. Subsequently data on single patients were extracted to perform a patient-level meta-analysis. PROSPERO registration number: CRD42021233248. The main outcomes were melanoma-specific survival (MSS) and progression-free survival (PFS) outcomes. Separate analyses were done of cases with complete information on histologic subtype, focusing on superficial spreading (SSM), nodular (NM) and spitzoid melanomas, as well as of those classified as de-novo (DNM) and acquired or congenital nevus-associated melanomas (NAM). The qualitative synthesis covered 266 studies; however, data on single patients were available from 213 studies including 1002 patients. Among histologic subtypes, NM had a lower MSS than both SSM and spitzoid melanoma, and a lower PFS than SSM. Spitzoid melanoma had a significantly higher progression risk than SSM and trended toward lower mortality. Focusing on nevus-associated status, DNM demonstrated better MSS after progression than congenital NAM, and no differences were highlighted in PFS. Our findings describe the existence of different biological patterns in paediatric melanoma. Specifically, spitzoid melanomas demonstrated intermediate behaviour between SSM and NM and showed a high risk of nodal progression but low mortality. This raises the question of whether spitzoid lesions are being over-diagnosed as melanoma in childhood.

Examining the role of wide excision margins in pediatric melanoma: A National Cancer Database analysis

BACKGROUND

Although adult guidelines are often applied to children, age-specific surgical margins have not been defined for pediatric melanoma.

PROCEDURE

Patients <20 years of age with invasive, cutaneous melanoma were identified using the 2004-2016 National Cancer Database and categorized as undergoing wide (>1 cm) or narrow (≤1 cm) excision. Unadjusted overall survival (OS) was compared using the Kaplan-Meier method and log-rank test. Multivariable Cox proportional hazard models were used to estimate the effect of excision margin on OS after adjustment for available covariates.

RESULTS

In total, 2081 patients met study criteria: 1338 (64.3%) patients underwent wide excision whereas 743 (35.7%) underwent narrow excision. Unadjusted OS was improved in the narrow-excision group (log-rank p = .01), which was consistent among patients with thicker (>1 mm) and thinner (≤1 mm) tumors. After adjustment for patient and tumor characteristics, we found no evidence of a difference in OS for patients who underwent narrow excision compared to patients who underwent wide excision (adjusted hazard ratio 0.57, 95% confidence interval 0.32-1.01, p = .053). There was no interaction between excision margin width and Breslow depth (p = .85), indicating that the effect of excision margin width on OS does not differ based on Breslow depth.

CONCLUSIONS

In this analysis, wide excision (>1 cm) does not appear to be associated with improved survival in children with melanoma regardless of tumor characteristics. Although further studies are needed to define optimal excision margins in pediatric melanoma, this study suggests that more narrow margins (≤1 cm) may be acceptable.

Diagnostic and prognostic classification of atypical spitzoid tumours based on histology and genomic aberrations: A prospective cohort study with long-term follow-up

BACKGROUND

Histological classification of atypical spitzoid tumours (ASTs) is unreliable, and categorisation of these lesions into benign and malignant is poorly reproducible. Here, we classified ASTs based on histology and chromosomal aberrations and explored the prognostic significance of genomic aberrations in a prospective cohort with a long-term follow-up.

PATIENTS AND METHODS

Histologically equivocal ASTs from 76 patients were analysed by array comparative genomic hybridisation (aCGH). Tumours were histologically assessed by a panel of dermatopathologist before and after aCGH and classified as benign, ambiguous or malignant. Chromosomal aberrations were correlated with an outcome.

RESULTS

Chromosomal aberrations were detected in 45 (59%) of 76 ASTs (median age: 16 years, range: 0-74; median follow-up: 90 months, range: 13-153). The initial histological diagnosis was changed upon presentation of aCGH results in 36 of 76 cases (47%). The final diagnostic interpretation classified 61% of the lesions as benign, 18% as ambiguous and 21% as malignant. Positive sentinel lymph node biopsies (6+/29) occurred at similar rates in all diagnostic groups (P = 0.83) and were not associated with an unfavourable outcome. Two patients had local recurrences, but none of the patients developed metastasis beyond the sentinel lymph node.

CONCLUSIONS

All ASTs had an excellent prognosis, even in cases with worrisome morphology and chromosomal aberrations. With no distant metastasis or death in long-term follow-up of 76 patients, no correlation between chromosomal aberrations and prognosis was possible. However, it seems likely that in larger cohorts, metastases would arise in cases with complex aberrations and these patients should undergo clinical follow-up.

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.

18F-FDG PET/CT Imaging in an Unusual Case of Cutaneous Melanoma Arising From Congenital Melanocytic Nevus in a Two-year-old Girl

Childhood malignant melanoma (MM) is extremely uncommon. We report an unusual case of cutaneous melanoma that developed from a medium-sized congenital melanocytic nevus (CMN) in a two-year-old girl. The patient had a history of CMN on the right hip, and she presented with a new ulcerative area with irregular borders and bleeding on CMN. Histopathological examination of the nevus revealed a MM. ¹⁸Florfluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography was performed for metastatic evaluation. The scan demonstrated metastatic increased ¹⁸F-FDG uptake in the right external iliac and inguinal lymph nodes.

Pediatric Melanoma-Diagnosis, Management, and Anticipated Outcomes

Melanoma is the most common skin cancer in children, often presenting in an atypical fashion. The incidence of melanoma in children has been declining. The mainstay of therapy is surgical resection. Sentinel lymph node biopsy often is indicated to guide therapy and determine prognosis. Completion lymph node dissection is recommended in selective cases after positive sentinel lymph node biopsy. Those with advanced disease receive adjuvant systemic treatment. Because children are excluded from melanoma clinical trials, management is based on pediatric retrospective data and adult clinical trials. This review focuses on epidemiology, presentation, surgical management, adjuvant therapy, and outcomes of pediatric melanoma.

Trends in pediatric skin cancer

PURPOSE OF REVIEW

To inform pediatric providers of the clinical characteristics, underlying genetic drivers, and therapeutic options for skin cancer arising in childhood and adolescence.

RECENT FINDINGS

The incidence of melanoma in pediatric patients has been declining in the past decades. Pediatric-specific diagnostic criteria should be utilized when assessing lesions concerning for melanoma to better account for the different presentations seen in pediatric disease compared with adults, such as an increased prevalence of amelanotic melanoma or frequent mimic of benign pediatric lesions. Pediatric melanoma often presents with a higher histopathologic stage and a higher Breslow depth as compared with adult melanoma. Pediatric nonmelanoma skin cancer including basal cell carcinoma and squamous cell carcinoma are associated with genetic conditions and immunosuppression, both iatrogenic and inherited.

SUMMARY

Melanoma in pediatric patients often presents differently from conventional adult melanoma, including Spitz melanoma and melanoma associated with congenital melanocytic nevi. Pediatric patients with nonmelanoma skin cancers should be evaluated for predisposing risk factors. More research on therapeutic options for pediatric skin cancer is vital to understanding the tolerance and response of our pediatric patients to therapies that are more frequently utilized in adult disease.

Paediatric malignant melanoma in Ireland: A population study and review of the literature

INTRODUCTION

Malignant melanoma is increasing in frequency worldwide; however, this disease is rare in children. As large-scale studies on paediatric melanoma are lacking, management is currently often based upon the understanding of the disease process in adults. The aim of this study was to characterise cases of paediatric melanoma diagnosed in the Republic of Ireland over a 21-year period.

METHODS

This was a retrospective, multicentre study using national data provided by the National Cancer Registry of Ireland and individual practitioners.

RESULTS

Twenty-four cases of melanoma treated in 11 different centres were included in the study. The median patient age at diagnosis was 15 years. The majority of cases arose on the limbs. The median Breslow thickness in patients of the pre-pubertal age group was 8.25 mm, while in children more than 13 years, it was 1.65 mm. Eight patients had disease recurrence and five patients died.

CONCLUSION

The diagnosis of melanoma remains rare in children. This study contributes to our current understanding of malignant melanoma in paediatric patients; however, further investigation of the disease characteristics in this group is necessary to achieve optimal management of these cases and therefore improve outcomes.

Sentinel Node Biopsy in Young Patients with Atypical Melanocytic Tumors of the Head and Neck

Objective

To examine the diagnostic value of the sentinel lymph node biopsy in pediatric through young adult head and neck melanocytic tumors of unknown malignant potential.

Study Design

Retrospective case series.

Setting

Single academic institution.

Subjects and Methods

Demographics, histology, and outcomes were examined in 14 patients aged 4 to 24 years with head and neck melanocytic tumors of unknown malignant potential. Information on age at diagnosis, primary lesion characteristics, and sentinel lymph node biopsy were compared.

Results

Of 14 patients meeting criteria for head and neck melanocytic tumors of unknown malignant potential, 8 patients underwent sentinel lymph node biopsy (57%). Of those, 4 biopsies (50%) had positive sentinel nodes. All patients undergoing sentinel lymph node biopsy had primary lesions greater than 1 mm depth or mitotic rate of at least 1 mitosis per mm². No patients had recurrence of their primary lesion at time of follow-up.

Conclusion

Our data show a high rate of node-positive sentinel lymph node biopsy for pediatric and young adult head and neck patients with melanocytic tumors of unknown malignant potential, supporting the value of sentinel lymph node biopsy in this population.

Cutaneous melanoma in adolescents and young adults

Cutaneous melanoma is rare in children, but has greater incidence in adolescents and young adults (AYAs). Diagnosis may be challenging due to its rarity in these age groups. Few studies have specifically addressed the topic of AYA melanoma. Though young-age melanoma may have particular biological characteristics, available data suggest that its clinical history is similar to that of adults. However, advances in treatment of adult melanoma have not been reflected in the treatment of AYAs. There is no standard treatment, and access to clinical trials is difficult for AYAs. Further efforts are needed to overcome these issues by improving cooperation with experts on adult melanoma.

[Expression of cancer testis (CT) antigens in pediatric and adolescent melanomas]

BACKGROUND

One of the main problems in the diagnostics of pediatric melanomas is the differentiation from benign dermal lesions typical for this age group, such as Spitz nevus. The biological behavior of pediatric melanomas differs considerably from that of melanomas in adults.

MATERIAL AND METHODS

Cancer testis (CT) antigens are named after their typical expression pattern since they are present in various types of malignant tumors but in normal adult tissues are solely expressed in testicular germ cells. Because of this tumor-associated expression pattern, CT antigens are regarded as potential targets for vaccine-based immunotherapy of cancer and might be used as diagnostic tools in surgical pathology. In adults, melanoma is among the tumors showing a high incidence of CT antigen expression; however, while there is ample knowledge about adult melanomas, little is known about the presence of CT antigens in pediatric melanomas. Consequently, the expression of CT antigens MAGE-A1, MAGE-A4, CT7/MAGE-C1, NY-ESO-1, and GAGE was analyzed in a series of pediatric melanomas. The study was restricted to cases of metastatic disease and/or fatal outcome. A total of 12 cases were available and immunohistochemically analyzed with monoclonal antibodies (mAb).

RESULTS

The expression of CT antigens was generally low and present in only 4 of 12 cases. This is in stark contrast to the expression of these antigens in adult melanomas. Moreover, the extent of expression was very limited with most cases showing only a focal CT antigen expression and only marked in very small tumor areas (<5%).

CONCLUSION

Despite the low case numbers this study indicates that CT antigens are most likely not useful as diagnostic markers in pediatric melanomas or as targets for vaccine-based immunotherapy. It supports the notion that pediatric melanomas show a different biological behavior than their adult counterparts.

Pediatric patients with cutaneous melanoma: A European study

INTRODUCTION

Cutaneous melanoma is rare in childhood and published studies have mainly been retrospective single-institution series or small case series. Given the absence of clinical protocols dedicated to pediatric melanoma, the treatment approach is generally extrapolated from the ones applied to adults.

METHODS

Coordinated by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT), this study collected patients prospectively registered between 2002 and 2012 under national cooperative projects dedicated to rare pediatric tumors in Italy, Poland, Germany, and France. Additional cases were collected from dermatology registries in Germany and Israel.

RESULTS

A total of 219 patients aged 0-18 years (median 14.4) were included in the analysis. Sentinel lymph node biopsy was performed in 112 patients (76% of those with Breslow thickness > 0.75 mm) and was positive in 37.5%. Systemic therapy was used in 33 cases. In stage III cases, survival rates were similar for patients who received (23 cases) or not (21 cases) adjuvant therapy. For the whole series, 3-year overall and disease-free survival rates were 91.4% and 84.0%, respectively (median follow-up 41.8 months). Tumor site, tumor stage, and ulceration influenced survival rates. Patients treated by pediatric oncologists (n = 140) were more likely to have advanced disease than those treated by dermatologists (n = 79).

DISCUSSION

This study would suggest that the clinical history of melanoma in children and adolescents might resemble that of adult counterpart. Cooperative efforts are needed to make new drugs more readily available to pediatric patients to increase the outcome of patient with advanced disease.

Contrasting features of childhood and adolescent melanomas

BACKGROUND/OBJECTIVES

Melanoma in children and adolescents is uncommon, and there are limited data on pediatric outcomes. Several studies have shown comparable survival rates in children and adults, but other research demonstrates that prepubescent children have more favorable outcomes. This study aims to compare childhood and adolescent melanoma.

METHODS

Retrospective cohort study of children who received a melanoma diagnosis at the Massachusetts General Hospital between January 1, 1995, and December 21, 2016. Childhood melanoma is defined as disease occurring in patients younger than 11 years old, and adolescent melanoma is defined as disease occurring in patients 11 to 19 years old. Patients diagnosed with ocular melanoma and borderline tumors of uncertain malignant potential were excluded. This analysis compares clinical, histopathologic, and outcome characteristics of childhood and adolescent melanoma.

RESULTS

Thirty-two children with melanoma were identified (12 children, 20 adolescents). The spitzoid melanoma subtype was significantly more common in children (6/12) than adolescents (2/20) (P = .01). Four adolescents and no children with melanoma died from melanoma, and survival was significantly different between the age groups (P = .04). Median follow-up time for survivors was 3.6 years.

CONCLUSIONS

These results suggest that children and adolescents present with different melanoma subtypes and that adolescents have a more aggressive disease course than children.

Higher than reported adolescent and young adult clinical trial enrollment during the "Golden Age" of melanoma clinical trials

Clinical trial enrollments in adolescents and young adults (AYA) with cancer have historically been lower than those in pediatric and older adult populations. We sought to examine therapeutic trial enrollment rates at our cancer center. We performed a retrospective evaluation of AYA patients treated before and after the first checkpoint inhibitor trial opened at our cancer center in 2007. We examined gender, stage at presentation and insurance status in terms of trial enrollment. We compared the trial participation rate of AYA patients with that of older adults. In this adult facility, 12.7% (1,831) of total patients were between age 15 and 39. Overall therapeutic clinical trial rate was 17.6% which increased to 19.8% since 2007. Both nodal disease or metastatic disease at presentation was associated with increasing odds of trial enrollment (OR = 5.36 and P < 0.001 for nodal disease and OR = 7.96 and P < 0.001 for metastatic disease). There was a nonstatistically significant trend toward improved 3-year overall survival in the AYA patients with advanced presentation that enrolled on clinical trials compared with those not enrolled on trials since 2007. AYA clinical trial enrollment at a comprehensive care center melanoma program was higher than reported in the literature overall for AYA patients. This 1,831 patient cohort may provide a foundation for more detailed investigation toward quantifying the effects of clinical trial enrollment in terms of age-specific benefits and toxicities for AYA patients with malignancies that have their peak incidence in older adults.

Pathology and genomics of pediatric melanoma: A critical reexamination and new insights

The clinicopathologic features of pediatric melanoma are distinct from those of the adult counterpart. For example, most childhood melanomas exhibit a uniquely favorable biologic behavior, save for those arising in large/giant congenital nevi. Recent studies suggest that the characteristically favorable biologic behavior of childhood melanoma may be related to extreme telomere shortening and dysfunction in the cancer cells. Herein, we review the genomic profiles that have been defined for the different subtypes of pediatric melanoma and particularly emphasize the potential prognostic value of telomerase reverse transcriptase alterations for these tumors.

Clinical and dermoscopic characterization of pediatric and adolescent melanomas: Multicenter study of 52 cases

BACKGROUND

Knowledge regarding the morphologic spectrum of pediatric melanoma (PM) is sparse, and this may in part contribute to delay in detection and thicker tumors.

OBJECTIVE

To analyze the clinicodermoscopic characteristics of PM.

METHODS

Retrospective study of 52 melanomas diagnosed in patients before the age of 20 years.

RESULTS

On the basis of its clinical, dermoscopic, and histopathologic characteristics, PM can be classified as spitzoid or nonspitzoid. The nonspitzoid melanomas (n = 37 [72.3%]) presented in patients with a mean age of 16.3 years (range, 8-20) and were associated with a high-risk phenotype and a pre-existing nevus (62.2%). The spitzoid melanomas (n = 15 [27.7%]) were diagnosed in patients at a mean age of 12.5 years (range, 2-19) and were mostly de novo lesions (73.3%) located on the limbs (73.3%). Whereas less than 25% of PMs fulfilled the modified clinical ABCD criteria (amelanotic, bleeding bump, color uniformity, de novo at any diameter), 40% of spitzoid melanomas did. Dermoscopic melanoma criteria were found in all cases. Nonspitzoid melanomas tended to be multicomponent (58.3%) or have nevus-like (25%) dermoscopic patterns. Spitzoid melanomas revealed atypical vascular patterns with shiny white lines (46.2%) or an atypical pigmented spitzoid pattern (30.8%). There was good correlation between spitzoid subtype histopathologically and dermoscopically (κ = 0.66).

LIMITATIONS

A retrospective study without re-review of pathologic findings.

CONCLUSION

Dermoscopy in addition to conventional and modified clinical ABCD criteria helps in detecting PM. Dermoscopy assists in differentiating spitzoid from nonspitzoid melanomas.

Paediatric melanoma

Paediatric melanoma, although rare, is the most common skin cancer in children. Our current knowledge on paediatric melanoma incidence trends is expanding, as several studies have addressed this issue with conflicting results. Known risk factors for paediatric melanoma include family history of melanoma, a previous history of malignancy, large congenital nevi, numerous melanocytic nevi, sunburns, increased UV exposure and a sun-sensitive phenotype. In younger children, melanoma more often presents with atypical features, such as a changing, amelanotic or uniformly coloured, often bleeding lesion, not fulfilling in most cases the conventional ABCDE criteria. The major differential diagnoses are melanocytic nevi, proliferative nodules in congenital nevi and atypical Spitz tumours. Moreover, in the younger age group non-Caucasian children are over-represented, tumours tend to be thicker and lymph nodes are often involved. Despite the frequent diagnosis at an advanced stage, the overall survival is fair in paediatric melanoma. Specific guidelines for management of melanoma in children do not exist, and most often the disease is treated similarly to melanoma in adults.

Pediatric Melanoma: A 35-year Population-based Review

Background:

Melanoma is a rare neoplasm in the pediatric population. Recent publications suggest a possible increase in incidence over the past few decades. The purpose of this study was to analyze trends in pediatric patients diagnosed with malignant melanoma in British Columbia (BC) in the past 35 years.

Methods:

A retrospective review was performed. All patients in BC diagnosed with melanoma before 18 years of age from 1979 to 2014 were included. Patient demographics, melanoma description, treatment details, and survival data were collected.

Results:

Seventy-eight subjects were identified for the study. Patients were equally distributed by sex. Sixty-one (78%) of the subjects were diagnosed in the postpubertal age (≥12 years old). The most common sites of occurrence were the extremities (n = 33) and the trunk (n = 27), with the location on the trunk showing the highest mortality rate (22%). All patients were surgically treated and some had additional chemotherapy (12) and/or radiotherapy (12). Fatal outcome was recorded in 12 of the 78 subjects, 10 of whom had postpubertal diagnosis. The average time from date of diagnosis to date of death was 9.3 years.

Conclusions:

The incidence of melanoma in the pediatric population remains exceedingly rare: less than 2.5 per million children younger than 18 years. The diagnosis is rarely made before puberty; the incidence is equal in males and females and has not changed over a 35-year time period in BC. Our study shows 85% survival with the majority of patients having had surgical excision only.

Lethal melanoma in children: a clinicopathological study of 12 cases

Melanoma in children is rare, representing 3% of paediatric malignancies and <1% of all melanomas. Very few detailed descriptions of bona fide lethal childhood melanomas exist in the literature. We performed a retrospective clinicopathological review of 12 paediatric (≤16 years) melanoma patients who died of metastatic disease, including detailed assessment of architectural and cytomorphological features. There were nine prepubertal patients (median age 7 years old) and three postpubertal cases (median age 15 years old). The patients died on average 45.7 months after diagnosis with the prepubertal subcohort showing a relatively longer time from diagnosis to death. The tumours were bulky (average tumour thickness=10mm), showed brisk mitotic activity (average mitotic count per mm²=7), and were formed by large expansile nodules with sheet-like growth pattern and infiltrative borders in the majority of cases (83%). Cytologically, large grossly pleomorphic epithelioid cells with massive eosinophilic macronucleoli were present in most cases (75%). In this cohort, we did not identify specific features of melanoma that were unique to children. Although melanomas are extremely rarely encountered in childhood, the above-cited unequivocal malignant features should prompt an outright diagnosis of melanoma even in a paediatric patient.

Cutaneous malignant melanoma in children and adolescents treated in pediatric oncology units

OBJECTIVES

Recent progress in the understanding of tumor biology and new targeted therapies has led to improved survival in adults with malignant melanoma (MM). MM is rare in children, especially before puberty. We report here our experience with pediatric patients with MM, describe the clinical presentation, treatment and evolution, and compare prepubescent and postpubescent disease.

METHODS

A retrospective, descriptive, national multicenter study was undertaken of 52 cases of MM in children and adolescents. Demographic, histopathology, treatment evolution data, and survival distributions are described.

RESULTS

Median age was 15 years (5-18). The tumors were often amelanotic (45%) and raised (83%), and Breslow thickness was greater than 4 mm in 35% of cases. Histological examination showed superficial spreading (n = 16) or spitzoid (n = 16) or nodular (n = 9) pattern. Twelve children (23%) were less than 10 years of age. The spitzoid histotype was more frequent in prepubescent children (seven of 12). Seventeen patients relapsed, of whom four had skin lesions initially diagnosed as benign. Ten patients died after relapse. Five-year event-free survival and overall survival were 62.7% (95% confidence interval [CI]: 45.3-76) and 75.5% (95% CI: 56.8-87.1), respectively.

CONCLUSIONS

MM appears to be different in prepubescent children, of whom most had a spitzoid histotype. Diagnosis can be difficult, leading to delay in treatment. New biological tools to identify targets for treatment in MM and to differentiate spitzoid melanomas from Spitz nevi now exist. As effective targeted therapies are now available, we recommend requesting biological examination of all melanocyte-derived skin lesions in children that could be malignant.

Pediatric melanoma

Childhood melanoma is a rare pediatric malignancy, with fewer than 500 new diagnoses annually. The incidence is increasing, particularly in the adolescent population. This review highlights the epidemiology, clinical presentation, and histopathologic challenges of pediatric melanoma. Surgical resection remains the cornerstone for localized and regionally advanced disease. Adjuvant therapies, including current options and potential novel therapeutics for this unique population will be discussed.

Pediatric and Adolescent Melanoma: A National Cancer Data Base Update

BACKGROUND

Studies suggest that the biology of pediatric and adolescent melanoma differs from that of adult disease. We report the largest series to date examining the natural history of pediatric and adolescent melanoma. We aim to elucidate the natural history of pediatric and adolescent melanoma and to examine the appropriateness of diagnostic and therapeutic modalities developed for adults and that are currently being used in children.

METHODS

A retrospective cohort study was conducted of patients with an index diagnosis of cutaneous non-metastatic melanoma from 1998 to 2011 using the National Cancer Data Base (NCDB; n = 420,416). Three age-based cohorts were analyzed: 1-10 years (pediatric), 11-20 years (adolescent), and ≥21 years (adult). Multivariate analyses were used to identify factors associated with overall survival (OS).

RESULTS

Pediatric melanoma patients have longer OS than their adolescent (hazard ratio [HR] 0.50, 95 % CI 0.25-0.98) and adult counterparts (HR 0.11, 95 % CI 0.06-0.21). Adolescents have longer OS than adults. No difference was found in OS in pediatric patients who are node-positive versus node-negative. In pediatric patients, sentinel lymph node biopsy and completion lymph node dissection are not associated with increased OS. In adolescents, nodal positivity is a significant negative prognostic indicator (HR 4.82, 95 % CI 3.38-6.87).

CONCLUSIONS

Age-based differences in melanoma outcomes warrant different considerations for diagnostic and therapeutic approaches in each group in order to maximize quality of life while minimizing complications and costs. Prospective, multicenter studies should evaluate the role of diagnostic procedures for pediatric patients.

Single institution experience of paediatric melanoma in Victoria, Australia

BACKGROUND/OBJECTIVES

Paediatric melanoma is an uncommon presentation of melanoma that accounts for 3% of all paediatric cancers. The objective was to describe a series of paediatric melanoma cases presenting to a state-wide tertiary referral service over the past 19 years.

METHODS

A search of the Victorian Melanoma Service database was performed to identify all patients under the age of 20 years diagnosed with melanoma from 1994 to 2013. Histological, demographic and phenotypical information for each patient was collected. Patients were matched against the Victorian Death Registry to identify those who had died. Fisher's exact test was used to examine associations. Melanoma-specific survival was estimated using the Kaplan-Meier method.

RESULTS

A total of 65 paediatric melanoma patients were included for analysis, in whom 72.3% of melanomas were diagnosed when they were 16-19 years of age with a mean age at diagnosis of 16 years. The mean Breslow thickness was 1.4 mm. It was greatest (3.4 mm) in the youngest age group (< 12 years of age). Ten patients developed nodal metastatic disease, eight of which progressed to visceral metastatic disease. The 5-year melanoma-specific survival rate was 96.8%.

CONCLUSION

This is the first descriptive epidemiological study of paediatric melanoma in Victoria. Further large, population-based, multi-institutional studies of paediatric melanoma are warranted to provide a clearer understanding of this group of melanoma patients.

Pediatric Melanoma and Atypical Melanocytic Neoplasms

Melanoma is uncommon in the pediatric age range, but is increasing in frequency and often presents with atypical features compared to the classic ABCDE criteria common to adult melanoma cases. Moreover, many melanocytic neoplasms in childhood pose diagnostic challenges to the pathologist, and sometimes cannot be unequivocally classified as benign nevi or melanoma. This chapter addresses the evaluation and management of pediatric patients with melanoma and atypical melanocytic neoplasms, including the roles of and unresolved questions surrounding sentinel lymph node biopsy, completion lymphadenectomy, adjuvant therapy, and treatment of advanced disease.

A Case of Pediatric Melanoma: Treatment Considerations in Advanced Disease

We document a 3-year-old healthy African American girl who developed malignant melanoma on her lower extremity. The clinical appearance offered little indication of the lesion’s severity (T4), and only the history of de novo presentation and disproportionate growth raised clinical suspicion. This case report highlights the subtle clinical findings of this condition and presents controversies related to surgical management of pediatric melanoma.

443 paediatric cases of malignant melanoma registered with the German Central Malignant Melanoma Registry between 1983 and 2011

BACKGROUND

Malignant melanoma is a very rare paediatric tumour. This study was performed in order to understand clinical features and prognosis of malignant melanoma in children and adolescents.

METHODS

443 patients ⩽ 18 years of age with malignant melanoma were prospectively registered with the German Central Malignant Melanoma Registry between 1983 and 2011. Cases were collected from 58 participating centres. 276 paediatric cases with a follow-up >3 months were evaluated for survival probabilities and prognostic factors by Kaplan-Meier method.

RESULTS

Age of diagnosis ranged from 3 months to 18 years (median age 16 years). The male to female ratio was 0.8 (202 male, 240 female). Most melanoma were located at the trunk (n = 195) and the lower extremity (n = 114). Patients with >3 months of follow-up (median 55 months) showed an overall survival (OS) of 94.8% in 5 years. Survival according to tumour stage was 98.5% for stage I (n = 190), 91.1% for stage II (n = 39) and 53.0% for stage III/IV tumours (n = 11). Worse outcome was seen in patients with nodular melanoma (OS 77.9%, n = 42) compared to superficial spread histotype (OS 100%, n = 138) or other histotype (OS 96.9%, n = 88) (p < 0.0001), in case of thicker tumours (Clark level IV or V, OS 87.1%, n = 84) compared to thinner tumours (Clark level I, II, III, OS 99.1%, n = 164) (p = 0.0008) and in case of ulceration (OS 65.6%, n = 17) compared to no ulceration (OS 99.2%, n = 182).

CONCLUSION

Patient and tumour characteristics in paediatric melanoma patients show no evident differences to adult melanoma cases. The same clinical approach as in adults should be used.

Atypical Spitz tumors in patients younger than 18 years

BACKGROUND

Diagnosis and proper management of atypical Spitz tumors in pediatric age are still controversial.

OBJECTIVE

We sought to investigate the clinicopathological and molecular features of atypical Spitz tumors in patients aged 18 years or younger.

METHODS

We performed a retrospective clinicopathological and fluorescence in situ hybridization study on 50 pediatric atypical Spitz tumors.

RESULTS

Parameters that were significantly correlated with a diagnosis of atypical Spitz tumors over Spitz nevus included asymmetry, level IV/V, lack of maturation, solid growth, nuclear pleomorphism, high nuclear-cytoplasmic ratio, atypical and deep mitoses, and more than 6 mitoses/mm(2). In the atypical Spitz tumors group, a significantly higher mitotic rate was observed in prepuberal age (P = .04). The 4-probe fluorescence in situ hybridization melanoma assay did not discriminate atypical Spitz tumors from Spitz nevi. Heterozygous 9p21 loss was found in 3 of 37 cases and homozygous 9p21 loss in 2 of 37 cases. Only 1 child experienced a fatal outcome, showing genetic abnormalities by melanoma fluorescence in situ hybridization probe and a heterozygous 9p21 deletion.

LIMITATIONS

The limited number of adverse outcomes did not allow the prognostic analysis of single morphologic features.

CONCLUSION

Pediatric atypical Spitz tumors are associated with minimal lethal potential. Atypical Spitz tumors require complete excision and careful follow-up while our data do not support any clinical benefit for the sentinel lymph node biopsy procedure and completion lymphadenectomy.

Atypical Spitzoid neoplasms: a review of potential markers of biological behavior including sentinel node biopsy

Atypical cutaneous melanocytic lesions, including those with Spitzoid features, can be difficult to categorize as benign or malignant. This can lead to suboptimal management, with potential adverse patient outcomes. Recent studies have enhanced knowledge of the molecular and genetic biology of these lesions and, combined with clinicopathological findings, is further defining their biological spectrum, classification, and behavior. Sentinel node biopsy provides important prognostic information in patients with cutaneous melanoma, but its role in the management of melanocytic lesions of uncertain malignant potential (MELTUMP) is controversial. This paper examines the role of molecular testing and sentinel node biopsy in MELTUMPs, particularly atypical Spitzoid tumors.

Long-term Survival after Metastatic Childhood Melanoma

Summary:

Malignant melanoma in children is very rare and accounts for only 1–3% of all melanomas. A congenital melanocytic nevus depending on the size of the lesion is one of the risk factors for developing childhood melanoma because of the possible malignant transformation. Childhood malignant melanoma is a potentially fatal disease. Surgical excision is the primary treatment of choice for malignant melanoma. Clinicians need to be aware of the possible malignant transformation in children with congenital melanocytic nevus because early diagnosis and treatment improves prognosis. The suspicion of malign melanoma must be in mind when evaluating a pigmented lesion in a pediatric patient. We present a case of a patient born with a congenital nevus diagnosed with metastatic childhood malignant scalp melanoma at the age of 6 years. The patient underwent surgical ablation and reconstruction and has survived 26 years without recurrence, thus representing an uplifting case of long-term survival of childhood melanoma.

On the Genesis of Neuroblastoma and Glioma

As the emergence of cancer is most frequent in proliferating tissues, replication errors are considered to be at the base of this disease. This review concentrates mainly on two neural cancers, neuroblastoma and glioma, with completely different backgrounds that are well documented with respect to their ontogeny. Although clinical data on other cancers of the nervous system are available, usually little can be said about their origins. Neuroblastoma is initiated in the embryo at a moment when the nervous system (NS) is in full expansion and occasionally genomic damage can lead to neoplasia. Glioma, to the contrary, occurs in the adult brain supposed to be mostly in a postmitotic state. According to current consensus, neural stem cells located in the subventricular zone (SVZ) in the adult are thought to accumulate enough genomic mutations to diverge on a carcinogenic course leading to diverse forms of glioma. After weighing the pros and cons of this current hypothesis in this review, it will be argued that this may be improbable, yielding to the original old concept of glial origin of glioma.

Age as a predictor of sentinel node metastasis among patients with localized melanoma: an inverse correlation of melanoma mortality and incidence of sentinel node metastasis among young and old patients

PURPOSE

We have previously reported that older patients with clinical stage I and II primary cutaneous. Melanoma had lower survival rates compared to younger patients. We postulated that the incidence of nodal metastasis would therefore be higher among older melanoma patients.

METHODS

The expanded American Joint Committee on Cancer melanoma staging database contains a cohort of 7,756 melanoma patients who presented without clinical evidence of regional lymph node or distant metastasis and who underwent a sentinel node biopsy procedure as a component of their staging assessment.

RESULTS

Although older patients had primary melanoma features associated with more aggressive biology, we paradoxically observed a significant decrease in the incidence of sentinel node metastasis as patient age increased. Overall, the highest incidence of sentinel node metastasis was 25.8 % in patients under 20 years of age, compared to 15.5 % in patients 80 years and older (p < 0.001). In contrast, 5-year mortality rates for clinical stage II patients ranged from a low of 20 % for those 20-40 years of age up to 38 % for those over 70 years of age. Patient age was an independent predictor of sentinel node metastasis in a multifactorial analysis (p < 0.001).

CONCLUSIONS

Patients with clinical stage I and II melanoma under 20 years of age had a higher incidence of sentinel lymph node metastasis but, paradoxically, a more favorable survival outcome compared to all other age groups. In contrast, patients >70 years had the most aggressive primary melanoma features and a higher mortality rate compared to all other age groups but a lower incidence of sentinel lymph node metastasis.

Cutaneous melanoma in children and adolescents: the Italian rare tumors in pediatric age project experience

OBJECTIVE

To describe a series of cutaneous melanoma in children collected by the Italian Rare Tumors in Pediatric Age project.

STUDY DESIGN

From 2000 to 2012, 54 patients younger than 18 years of age were prospectively registered and treated at 12 Italian pediatric centers on the basis of the same diagnostic/therapeutic recommendations and with the same forms to record clinical data.

RESULTS

Considering the estimated annual incidence in Italy, the registered cases accounted for 30% of those expected in children and 10% of adolescents. Clinically, 47% of the tumors were amelanotic and 81% were raised, 39% of cases had tumor thickness >2 mm, and 36% had lymph node involvement. For the whole series, 5-year event-free survival and overall survival rates were 75.2% and 84.6%, respectively. Patient survival correlated with tumor stage and ulceration. No relapses were recorded for T1-2 (thickness <2 mm), N0, and stage 0-I-II cases.

CONCLUSION

We suggest that the variables influencing survival in children with melanoma are the same as for adults, the clinical approach used in adults is feasible in children, and pediatric cases are more likely to have advanced disease at diagnosis but similar survival. New effective drugs are needed for advanced disease, and biological studies and international cooperative schemes are warranted.

Controversies in the evaluation and management of atypical melanocytic proliferations in children, adolescents, and young adults

The rising incidence of melanoma in children has brought increased attention to the clinical and pathologic diagnosis of pigmented lesions in the pediatric age group. Although melanoma in infancy and early childhood is often associated with large congenital nevi, in older children and teenagers it is most often sporadic, occurring in patients with a low skin phototype and substantial sun exposure. The rarity of this potentially fatal disorder demands astute clinical attention and a high index of suspicion for atypical lesions in pediatric patients. The challenges include the difficult decision of whether to biopsy and an often equivocal pathologic diagnosis. These diagnostically challenging and equivocal lesions lead to a degree of uncertainty regarding additional workup, prognosis, potential therapy, and follow-up plans. Consultation with a specialty dermatopathologist can be very helpful, and advanced molecular diagnostic techniques may be used in selected circumstances. Although still controversial, good evidence exists to justify a role for sentinel lymph node biopsy. Patients with atypical melanocytic proliferations have a high rate of positive sentinel lymph nodes; however, their outcomes are clearly better than in similarly staged adults with conventional melanoma. With the multiple variables involved and the relative lack of prospectively derived evidence, clinical decision-making is challenging and patients and families may experience considerable stress. This article provides data and weighs the pros and cons of a rationale for decision-making in pediatric and young adult patients with diagnostically challenging melanocytic lesions.

Evidence-based clinical practice guidelines on the use of sentinel lymph node biopsy in melanoma

Sentinel lymph node biopsy (SLNB) was introduced in 1992 to allow histopathologic evaluation of the "sentinel" node, that is, the first node along the lymphatic drainage pathway from the primary melanoma. This procedure has less risk of complications than a complete lymphadenectomy, and if the sentinel node is uninvolved by tumor the likelihood a complete lymphadenectomy would find metastatic disease in that nodal basin is very low. SLNB is now widely used worldwide in the staging of melanoma as well as breast and Merkel cell carcinomas. SLNB provides safe, reliable staging for patients with clinically node-negative melanomas 1 mm or greater in thickness, with an acceptably low rate of failure in the sentinel node-negative basin. Evidence-based guidelines jointly produced by ASCO and the Society of Surgical Oncology (SSO) recommend SLNB for patients with intermediate-thickness melanomas and also state that SLNB may be recommended for patients with thick melanomas. Major remaining areas of uncertainty include the indications for SLNB in patients with thin melanomas, pediatric patients, and patients with atypical melanocytic neoplasms; the optimal radiotracers and dyes for lymphatic mapping; and the necessity of complete lymphadenectomy in all sentinel node-positive patients.