Osteosarcomatous changes in malignant melanoma. Immunohistochemical and ultrastructural studies of a case

Am J Dermatopathol. 1990 Apr;12(2):162-8.


Immunohistochemical and ultrastructural studies were conducted to elucidate the nature and origin of osteosarcomatous changes in malignant melanoma in a 43-year-old Japanese man. Immunohistochemical studies with the use of antisera against human S-100 protein and neuron-specific enolase demonstrated positive reactions in the tumor cells within the osteosarcomatous area. Ultrastructurally, the neoplastic cells showed marked similarities to those from osteosarcomas. Additionally, occasional neoplastic cells contained round or ellipsoidal osmiophilic organelles, presumably melanosomes. These findings indicate that osteosarcomatous changes in malignant melanoma are produced by the dedifferentiated melanoma cells.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Foot Diseases / metabolism
  • Foot Diseases / pathology*
  • Humans
  • Immunohistochemistry
  • Male
  • Melanoma / metabolism
  • Melanoma / ultrastructure*
  • Microscopy, Electron
  • Osteosarcoma / metabolism
  • Osteosarcoma / ultrastructure*
  • Phosphopyruvate Hydratase / metabolism
  • S100 Proteins / metabolism
  • Skin Neoplasms / metabolism
  • Skin Neoplasms / ultrastructure*


  • S100 Proteins
  • Phosphopyruvate Hydratase