Malignant melanoma on congenital naevus: a case of degeneration in a 6-month-old child with severe histological criteria

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.

[Early-onset melanoma (congenital, neonatal, infantile): A systematic review of literature cases]

INTRODUCTION

Neonatal and infantile malignant melanoma is rare. It may be difficult to diagnose and often carries a poor prognosis.

MATERIAL AND METHODS

We decided to review the data on congenital, neonatal and infantile malignant melanomas in order to understand their presentation (clinical, histological, molecular), diagnosis, management and outcomes. We performed a literature search of all cases of early-onset melanoma published in PubMed from its inception to March 2019 using the following keywords: "malignant melanoma" OR "melanoma" OR "pigmented nevus" OR "malignant pigmented" AND "infantile" OR "congenital" OR "children" OR "childhood" OR "infancy" OR "neonatal". Congenital melanoma associated with maternal-foetal transmission was not included in the study.

RESULTS

Sixty-five articles were selected and 85 cases were included in the study. Most patients were male (sex ratio: 1.6). The average age at diagnosis was 5.5 months (minimum-maximum: 0-24 months). The main site reported for congenital melanoma was the head-and-neck area and for neonatal and infantile melanoma the trunk. Half of all patients had a metastatic disease at the time of diagnosis. In metastatic cases, the prognosis was poor with the exception of patients undergoing complete excision of the tumour and metastases. The main treatment for cutaneous melanomas and operable metastasis was surgery, and secondarily, chemotherapy/immunotherapy.

CONCLUSION

Neonatal and infantile malignant melanoma are rarely reported and not well-documented. It is necessary to collect additional cases to improve our knowledge of this rare disease.

Congenital malignant melanoma of the scalp in a 25-day-old neonate

We present a case of congenital malignant melanoma of the scalp in a neonate. The child was born through caesarean section with a swelling, the size of a tennis ball, on the posterior scalp. At presentation to the clinic at 25 days after birth, the swelling had significantly increased in size and ulcerated. An excision was carried out but, because of extensive haemorrhage and haemodynamic instability, the procedure was limited to subtotal resection. Later on, completion of the excision and flap coverage of the wound were performed. After an initial stable course of a few months, the child came back with local recurrence. A re-excision was planned but the child developed pneumonia resulting in sepsis leading to the demise of the child. The report adds to the literature by describing a rare entity and challenges of managing large vascular scalp lesions with complete excision and defect coverage.

Pathologic features of pediatric head and neck melanoma

Although malignant melanoma is rare in children, its incidence is steadily increasing, and it is potentially lethal. Few studies have examined head and neck melanoma in children, and even fewer have focused on the histopathologic features of melanoma within this anatomic region. To further the understanding of this entity, we examined pathology specimens from nine subjects age 18 years and younger with an original diagnosis of head or neck melanoma. The anatomic locations of these primary melanomas were the face and nose (n = 4), scalp and neck (n = 4), and ear (n = 1). The cases included seven superficial spreading melanomas, one unclassified (possible nodular) melanoma, and one melanoma in situ. No melanomas demonstrating desmoplastic or spindle cell morphologies were noted upon review. Breslow depth ranged from 0 to 2.9 mm (mean 1.3 mm, median 0.6 mm), with Clark level ranging from I to V. Pagetoid scatter was found in eight cases. Other notable features included regression (n = 5), ulceration (n = 1), and associated melanocytic nevus (n = 4). We did not observe any small cell variants; all nine cases had an epithelioid appearance. Nor was any melanoma-associated mortality observed at last follow-up (mean 60.4 mos, median 48 mos, range 2-174 mos). These histopathologic features were consistent with adult-type melanoma, which is in agreement with other histopathologic studies of melanoma in children.

[Asymptomatic neonatal neurocutaneous melanosis]

Giant congenital nevi in 1% of cases are associated with anomalies of the central nervous system, which are characteristic of neurocutaneous melanosis. When neurocutaneous melanosis becomes symptomatic, it is associated with a poor prognosis. With recommended neonatal screening, asymptomatic neonatal cases are being discovered more frequently. On the basis of this observation, we consider various aspects of this association.