Prepubertal 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.

Melanomas in prepubescent children: review comprehensively, critique historically, criteria diagnostically, and course biologically

Our series was comprised of 11 children age 10 years or younger (6 were younger than age 5) with primary cutaneous melanoma. All of the melanomas occurred de novo and all metastasized; one child died. In no instance was melanoma a clinical consideration, and in none did the histopathologist who first "signed out" the case make a diagnosis of melanoma. Despite the inability of clinicians and pathologists to diagnose correctly, with repeatability, melanomas that develop in children yet to be pubescent, those neoplasms, nonetheless, are melanomas and, therefore, criteria employed currently for diagnosis of melanoma, especially clinically, must be refined in order that they be applicable equally to melanomas in pre- and postpubescents. The vaunted ABCDs (Asymmetry, Border irregular, Color variability, Diameter >6.0mm) surely do not work for melanomas that appear in children who are prepubescent. Additionally, melanomas that occur in these children have distinctly different architectural and cytopathological features from those that arise in postpubescents, often being confused as they are by conventional microscopy with a Spitz's nevus. As a rule, melanomas in prepubescent children grow much more rapidly then those in adults but, like them, have the capability to disseminate widely and cause death.

Malignant melanoma in children: its management and prognosis

Malignant melanoma is rare in children, representing 1% to 3% of all pediatric malignancies. Thirty-three children with malignant melanoma were treated at St Jude Children's Research Hospital from 1967 to 1988. Their ages ranged from 1 day to 20 years (median, 12 years); 23 were boys and 10 were girls; and 5 of the 33 (15%) were black. Four of the 33 children had been treated for a previous malignancy. In 3, melanoma arose within a bathing trunk nevus. The extremity was the most common site (13), followed by the trunk (9), head and neck (7), and perineum (1). In 3 patients the primary site could not be determined. Upon initial presentation to St Jude Hospital, 17 patients had localized disease (stage I), 10 had regional node involvement (stage II), and the remaining 6 patients had disseminated disease (stage III). Using both Clark's level and Breslow's thickness as indicators, the incidence, initial stage, prognosis, and survival were compared. By Clark's level, 7 patients, (6 of whom were stage I) were level II or III, and 22 patients were level IV or V. Though 16 of 22 level IV and V patients were initially stage I, 10 patients eventually developed progressive disease. Similar observations were noted when using Breslow's thickness to evaluate the primary. In 5 of 27 evaluable patients, Breslow's depth of invasion was less than 1.5 mm. All 5 of these patients were diagnosed with stage I disease and have not shown progressive disease.