Pancreatic PEComa: a case report with ultrastructural localization of HMB-45 within melanosomes

Ultrastruct Pathol. 2012 Apr;36(2):124-9. doi: 10.3109/01913123.2011.642463.

Abstract

PEComas (perivascular epithelioid cell tumors) represent a group of mesenchymal neoplasms showing characteristic morphologic, immunohistochemical, ultrastructural, and genetic features. These neoplasms are usually considered benign, being often well circumscribed by a thin capsule and showing scarce atypia. However, in some cases, they show local invasion and multiple metastases and cause the patient's death. PEComas have been found in many locations, but only 7 cases have been described in the pancreas to date. Here, the authors report an additional case of this rare neoplasm and demonstrate the HMB-45 immunoreactivity of melanosomes or premelanosomes at the ultrastructural level.

Publication types

  • Case Reports

MeSH terms

  • Biomarkers, Tumor
  • Epithelioid Cells / metabolism
  • Epithelioid Cells / pathology
  • Female
  • Humans
  • Melanoma-Specific Antigens / metabolism*
  • Melanosomes / metabolism*
  • Melanosomes / pathology
  • Middle Aged
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology
  • Perivascular Epithelioid Cell Neoplasms / metabolism*
  • Perivascular Epithelioid Cell Neoplasms / pathology
  • Treatment Outcome
  • gp100 Melanoma Antigen

Substances

  • Biomarkers, Tumor
  • Melanoma-Specific Antigens
  • PMEL protein, human
  • gp100 Melanoma Antigen