title: Metastatic nevoid melanoma in a 4 1/2-year-old child.
abstract: BACKGROUND
  Childhood melanoma is a rare and controversial diagnosis.
  
  
  METHODS
  We present the case of a 4 1/2-year-old child found to have an expanding, elevated pigmented lesion on her back.
  
  
  RESULTS
  The biopsy showed a symmetrical, well circumscribed lesion. However, higher magnification revealed sheets of nevoid cells infiltrating deep into the dermis, lacking maturation, and exhibiting a high mitotic rate (average 5/10 high-power field) with deep mitoses. The possibility of nevoid melanoma was raised, and re-excision and sentinel lymph node (SLN) biopsy were recommended. Two SLNs were positive for melanoma, verified by immunohistochemical staining. In order to further characterize this melanoma, we performed immunohistochemistry for the tumor-suppressor p53, proliferation marker MIB-1, and oncogenes Bcl-2, cyclin D-1, and MDM-2. Staining for p53 was diffusely positive in the primary and the metastasis; MIB-1 showed moderate proliferative rate in the primary (approximately 10%); Bcl-2 was weakly positive in the primary and showed focal staining in the metastasis; cyclin D-1 was strongly positive in the primary and metastasis; and MDM-2 staining showed scattered positive cells in both lesions.
  
  
  CONCLUSIONS
  These findings are consistent with a metastatic nevoid melanoma arising in the absence of predisposing disease in a young child, a distinctly unusual occurrence.
authors.affiliation: Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA. dcassari@uci.edu
authors.forename: David S
authors.initials: DS
authors.lastname: Cassarino
authors.forename: Douglas R
authors.initials: DR
authors.lastname: Fullen
authors.forename: Vernon K
authors.initials: VK
authors.lastname: Sondak
authors.forename: Paul H
authors.initials: PH
authors.lastname: Duray
mesh_terms: D001415:Back; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008197:Lymph Node Excision; D008207:Lymphatic Metastasis / Q000473:pathology; D008545:Melanoma / Q000378:metabolism / Q000473:pathology*; D009506:Nevus / Q000378:metabolism / Q000473:pathology*; D021701:Sentinel Lymph Node Biopsy; D012878:Skin Neoplasms / Q000378:metabolism / Q000473:pathology*