Historical Perspective: Barnhill et al., 1995

 
In 1995, Barnhill and coworkers55 studied 23 children 15 years of age or younger who were referred to Children's Hospital in Boston with a diagnosis of melanoma, and they shared their observations about the neoplasms in these children in an article titled, "Cutaneous melanoma and atypical Spitz tumors in childhood." The neoplasms were separated by them into four groups, namely, "small cell melanoma," "adult-like melanoma," "Spitz-like melanoma," and "atypical Spitz tumors." Barnhill and associates identified five children whom they considered to have the "small cell variant" of melanoma. Those neoplasms were confined to the scalp, and all the children who had them were dead of metastasis of melanoma 5 to 12 months after diagnosis of the primary neoplasm had been made. The melanomas ranged in thickness from 2.8 mm to 15.0 mm. Two of the children were 10 years of age or less, both of them being 4 years old; the other 3 children were 12 years old and one of them was 13. Of this supposed variant of melanoma, Barnhill and colleagues said this:
 
"Histologically, these tumors[small-cell variant of melanoma in children] contained a significant component of relatively small cells with round or oval nuclei and generally scant cytoplasm, usually disposed in sheets. The general impression was a monomorphous population of cells, suggesting lymphoma, a small round-cell tumor, or a melanocytic nevus. . . . Two melanomas were deeply invasive into subcutaneous fat and were characterized by irregular nodules of melanoma cells. Three melanomas had intradermal components, whereas two were entirely dermal. . . . One melanoma developed in association with a congenital nevus."
 
Six examples of the "adult" variant of melanoma were recognized by Barnhill et al., who categorized them histopathologically as "pagetoid," "nodular," "spindle, polygonal cell," "lentiginous, polygonal cell," and "lentiginous." About the histopathologic findings in the "adult" variant of childhood melanoma, Barnhill and associates made these statements:
 
"Two melanomas displayed a prominent pagetoid intraepidermal component, in one case, in situ, and in the other, invasive to 1.12 mm. The latter in situ melanoma arose in association with a compound dysplastic nevus . . . Three melanomas (two in situ) showed mainly basilar intraepidermal (lentiginous) patterns of melanocytic proliferation. . . . The invasive melanoma occurred on the cheek of a 3-year-old male with xeroderma pigmentosa."
 
Three children 10 years of age or younger in the study of Barnhill et al. had the "adult" type of melanoma, their ages being 4, 3, and 9 years; all were alive 12, 4, and 4 months, respectively, after diagnosis of the primary neoplasm had been made. The 4-year-old child was said to have the "spindle, polygonal cell" type of adult melanoma, the 3-year-old the "lentiginous" type, and the 9-year-old the "pagetoid" type. Two adolescents, both 15 years of age, died of metastasis from this type of melanoma. According to Barnhill and associates, the 4-year-old and the 9-year-old both had a melanoma that was in situ.