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.

Higher rates of regional disease but improved outcomes in pediatric versus adult melanoma

BACKGROUND

Malignant melanoma is rare in the pediatric population and management is largely extrapolated from adult guidelines. Adult data have shown that immediate completion lymph node dissection (CLND) does not improve overall survival in selected patients with clinically node negative, sentinel lymph node-positive disease. Current nodal management in children is unknown.

METHODS

The National Cancer Database (NCDB) was queried for patients with melanoma from 2012-2017 and patients categorized as pediatric (≤18 years, n=962) or adult (n=327,987). Factors associated with CLND in children with positive SLNB were evaluated in multivariable analysis. Kaplan-Meier survival analysis was performed.

RESULTS

Compared to adults, children present with thicker primary tumors (T3 or T4 26.5% vs 15.5%, p<0.001), resulting in higher rates of nodal assessment with SLN biopsy or LND (60.2% vs 36.6%, p<0.001) and higher rates of regional nodal disease (35.1% vs 23.4%, p<0.001). Children underwent higher rates of CLND after SLN biopsy (10.4% vs 4.1%) and upfront lymph node dissection (15.2% vs 8.7%). A decreased rate of CLND was noted in 2017 compared to 2012 (odds ratio (OR) 0.16 (p=0.005). CLND was performed more often on multivariable analysis for older pediatric age (>12 years, OR=1.6, p=0.037) and lower extremity primary (OR=0.29, p<0.001). Children with regional nodal disease have improved 3-year overall survival compared to adults (96.5% vs 71.0%, p<0.001).

CONCLUSIONS

Children with melanoma have higher rates of nodal disease but better survival than adults. As in adults, there has been a recent increase in close nodal observation rather than CLND for patients with positive SLN. Further study of nodal surveillance for pediatric patients is warranted.

Racial Differences in the Prognosis and Survival of Cutaneous Melanoma From 1990 to 2020 in North America: A Systematic Review and Meta-Analysis

Background

Factors influencing the difference in the diagnosis and treatment of melanoma in racial minority groups are well-described in the literature and include atypical presentations and socioeconomic factors that impede access to care.

Objective

To characterize the differences in melanoma survival outcomes between non-Hispanic white patients and ethnic minority patients in North America.

Methods

We conducted searches of Embase via Ovid and MEDLINE via Ovid of studies published from 1989 to August 5, 2020. We included observational studies in North America which reported crude or effect estimate data on patient survival with cutaneous melanoma stratified by race.

Results

Forty-four studies met our inclusion criteria and were included in this systematic review. Pooled analysis revealed that black patients were at a significantly increased risk for overall mortality (HR 1.42, 95% CI, 1.25-1.60), as well as for melanoma-specific mortality (HR 1.27, 95% CI, 1.03-1.56). Pooled analyses using a representative study for each database yielded similar trends. Other ethnic minorities were also more likely report lower melanoma-specific survival compared to non-Hispanic white patients.

Conclusion

Our results support findings that melanoma patients of ethnic minorities, particularly black patients, experience worse health outcomes with regards to mortality. Overall survival and melanoma-specific survival are significantly decreased in black patients compared to non-Hispanic white patients. With the advent of more effective, contemporary treatments such as immunotherapy, our review identifies a gap in the literature investigating present-day or prospective data on melanoma outcomes, in order to characterize how current racial differences compare to findings from previous decades.

THE demographics and trends in pediatric melanoma in the United States: An analysis of the National Cancer Database

BACKGROUND/OBJECTIVE

Relative to adults, rates of melanoma are lower in children. Due to its rarity, it is difficult to assess the incidence, trends, and outcomes of this malignancy. Much of our understanding comes from single institution or regional cancer registries which may not be large enough to detect subtleties in the burden of pediatric melanoma.

METHODS

Data from the 2004 to 2016 National Cancer Database were analyzed; this database captures approximately 70% of all cancer diagnoses in the United States.

RESULTS

Our analysis consisted of 1903 cases. A majority were White (89.8%), the mean age was 12.4 years, and the ratio of females: males was 1.2:1.0. The most common anatomic location was the trunk (31.1%). Between 2004 and 2016, a decreasing trend in the number of new melanoma cases was observed. Comparing histologic subtype by age, there was an increased percentage of nodular and epithelioid and spindle cell tumors in the pre-teen children and a greater percentage of superficial spreading tumors in teenagers. Overall, a majority of cases were stage 0 or I (56.9%), with relatively few stage IV cases (2.0%). A 5-year all-cause survival of greater than 90% was observed for stage I-III tumors, with stage IV tumors having a 5-year all-cause survival of 34.4%.

CONCLUSION

Comparable to previous studies, pediatric melanoma occurred most often in Whites, females, and adolescents. However, we detected a decreasing trend in new cases, noted differences between histologic subtype and age, and observed a 5-year all-cause survival rate of greater than 90% for stage I-III tumors.

Age and Melanocytic Lesions

Age plays a dynamic role in incidence, presentation, and extent of disease for cutaneous melanoma. Even within the spectrum of juvenile melanoma, there exists a range of spitzoid and nonspitzoid melanocytic and melanoma lesions. Spitzoid melanomas, a more favorable disease in juvenile patients, are malignant lesions and require treatment as such. Lymph node metastases in melanoma occur at lower rates in older patients compared with younger counterparts, yet the rate of metastases is still high. Age appears to play an important role in the development and progression of melanoma, and understanding the differences across age populations is important when counseling patients.

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.

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.

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.