[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.

[The role of new molecular tests in the diagnosis of melanoma in a setting of congenital nævus in an infant]

INTRODUCTION

Congenital and infantile melanomas are extremely rare. We report a case of a child presenting at birth with a giant congenital nevus complicated by melanoma and on long-term follow-up with exploration using new immunohistochemistry and molecular biology tools.

OBSERVATION

A new-born girl presented at birth with a large congenital cervico-mandibular tumour with para-pharyngeal extension and underlying osteolysis. At 7 months, histology and immunohistochemistry of the operative specimen revealed nodules with atypical features (mitotic figures, necrosis and positive expression of KI67 and P53 in approximatively 50 % of the melanocytic nuclei). A diagnosis was made of infantile melanoma associated with congenital nevi. Repeated surgery and monitoring (clinical and imaging) were performed. At the age of 7 years, as there was no evidence of metastatic lesions, further analyses were performed on the initial operative specimen. Investigation of transcription factor expression using immunohistochemistry, comparative genomic hybridization and histology-guided mass spectrometry, although suspect, did not in itself support a diagnosis of melanoma. Finally, at the age of 7 years, hepatic and pulmonary metastases were reported. Despite combined immunotherapy with ipilimumab and nivolumab, the child died 5 months later.

CONCLUSION

This case illustrates the complexity of diagnosis of infantile melanoma and the risk of metastatic involvement long after the initial diagnosis. Diagnosis may be difficult and necessitates expert advice and the application of several recent methods to reach a conclusion and initiate appropriate treatment.