Childhood melanoma: a clinicopathological study of 22 cases

Childhood melanoma is a rare disease with an estimated incidence of one per million per year. Careful study of childhood melanoma patients is critical due to the limited data currently available pertaining to this disease. Twenty-two children 15 years of age or under with malignant melanoma were treated at the Pigmented Lesion Clinic of Massachusetts General Hospital over a 33-year period. The medical records of all patients were reviewed, as well as the histologic characteristics of the lesions. Patients who were initially diagnosed with malignant melanoma but on review found to have Spitz naevi were not included in our study. Ten patients were boys and 12 were girls. The median ages of the boys and girls in our study were 12.9 and 13.6 years, respectively. Among the classified primary melanomas, 10 were superficial spreading, three were borderline/minimal deviation, two were nodular and one was melanoma in situ. Four of 22 patients had a documented family history of melanoma, and two additional patients had a family history of dysplastic naevi. A majority of lesions (14/22) arose in association with a precursor lesion. Two children died of disease at 1 and at 7 years following initial diagnosis. Eight patients had documented metastases. Since the majority of melanomas arose in association with a precursor lesion, follow-up of children with congenital and/ or dysplastic naevi is recommended. An interesting finding was the sometimes paradoxical behaviour of relatively thin lesions with metastases. Thus, a high index of suspicion is needed by the clinician confronted with melanocytic lesions of childhood. We found children from age 12 to 15 to be more at risk for the development of melanoma than younger children. Melanoma presenting before the age of 10 is very unusual.