Follicular dendritic cell sarcoma involving the parotid gland with expression of the melanocytic marker PRAME

J Hematop. 2024 Dec;17(4):271-274. doi: 10.1007/s12308-024-00605-7. Epub 2024 Oct 9.

Abstract

Follicular dendritic cell sarcoma is a rare mesenchymal neoplasm arising from follicular dendritic cells (FDC) of lymphoid follicles. While the majority of FDC sarcoma cases arise within lymph nodes, approximately 30% manifest in extranodal sites. Only 4 prior occurrences of intra-parotid FDC sarcomas have been documented. We are reporting a rare case of FDC of the parotid gland in a 65-year-old male with a questionable history of B-cell lymphoma. The patient underwent a right total parotidectomy and bilateral neck dissection. A diagnosis of follicular dendritic cell (FDC) sarcoma was made, with one positive intra-parotid node. The malignant cells expressed the characteristic markers for FDC sarcoma but with positivity of the melanocytic marker PRAME. This is a case of FDC sarcoma with an unusual extranodal localization in the parotid gland. Immunohistochemistry was useful in making a diagnosis although the positivity for the melanocytic marker PRAME was unusual and unreported before.

Keywords: Follicular dendritic cells; Melanoma; PRAME; Parotid gland; Sarcoma.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Antigens, Neoplasm* / analysis
  • Antigens, Neoplasm* / metabolism
  • Biomarkers, Tumor* / analysis
  • Biomarkers, Tumor* / metabolism
  • Dendritic Cell Sarcoma, Follicular* / diagnosis
  • Dendritic Cell Sarcoma, Follicular* / metabolism
  • Dendritic Cell Sarcoma, Follicular* / pathology
  • Dendritic Cell Sarcoma, Follicular* / surgery
  • Humans
  • Immunohistochemistry
  • Male
  • Parotid Gland / metabolism
  • Parotid Gland / pathology
  • Parotid Gland / surgery
  • Parotid Neoplasms* / diagnosis
  • Parotid Neoplasms* / metabolism
  • Parotid Neoplasms* / pathology
  • Parotid Neoplasms* / surgery

Substances

  • PRAME protein, human
  • Antigens, Neoplasm
  • Biomarkers, Tumor