Malignant melanoma arising in a blue nevus with features of pilar neurocristic hamartoma

J Cutan Pathol. 1993 Oct;20(5):459-64. doi: 10.1111/j.1600-0560.1993.tb00672.x.


A 65-year-old man presented with a history of a giant blue plaque of the parietal scalp since childhood. Biopsy revealed a cellular blue nevus. The blue nevus was observed for 10 years and thought to be unchanged until a new adjacent lesion was noted. Biopsy of the new lesion revealed metastatic malignant melanoma. A wide excision was performed of the original lesion which revealed malignant melanoma arising in a blue nevus. Areas within the blue nevus were consistent with a pilar neurocristic hamartoma, whereas other areas were consistent with a common blue nevus. Subsequent satellite metastases developed, with early metastases resembling blue nevi except for the absence of a stromal component and the presence of hyperchromatic nuclei. Later metastases were typical of metastatic melanoma. This case illustrates the uncommon evolution of malignant melanoma from a blue nevus. The histological features and relationship between melanoma, blue nevus, and pilar neurocristic hamartoma are reviewed.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Hair Diseases / pathology*
  • Hamartoma / pathology*
  • Humans
  • Lymphatic Metastasis
  • Male
  • Melanoma / pathology*
  • Melanoma / secondary
  • Neoplasms, Second Primary / pathology*
  • Neural Crest
  • Nevus, Blue / pathology*
  • Nevus, Blue / secondary
  • Scalp Dermatoses / pathology*