Phosphaturic mesenchymal tumor: A chondromyxoid fibroma-like type

J Dermatol. 2023 Nov;50(11):1484-1487. doi: 10.1111/1346-8138.16870. Epub 2023 Jun 22.

Abstract

Phosphaturic mesenchymal tumor (PMT) is a rare neoplasm that causes tumor-induced osteomalasia (TIO) in most affected patients, usually through the production of fibroblast growth factor 23 (FGF23). This tumor is often misdiagnosed due to its relative rarity and its widely varied histomorphologic spectrum. Here we describe a case of a 78-year-old woman who presented with a left middle tumor without symptoms of TIO. The histological features resembled chondromyxoid fibroma with smudgy calcification in the tumor matrix. In addition, we evaluated FGF23 expression through immunohistochemical study and reverse transcription polymerase chain reaction. PMT with chondromyxoid fibroma features are extremely rare. Examining the expression of FGF23 is useful in the diagnosis of PMT.

Keywords: Phosphaturic mesenchymal tumor; chondromyxoid fibroma-like feature; fibroblast growth factor 23; nonphosphaturic variant.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Female
  • Fibroblast Growth Factors
  • Fibroma* / diagnosis
  • Fibroma* / surgery
  • Humans
  • Mesenchymoma* / diagnosis
  • Mesenchymoma* / pathology
  • Mesenchymoma* / surgery
  • Neoplasms, Connective Tissue* / diagnosis
  • Neoplasms, Connective Tissue* / surgery
  • Osteomalacia*
  • Paraneoplastic Syndromes* / diagnosis
  • Paraneoplastic Syndromes* / etiology
  • Soft Tissue Neoplasms* / diagnosis

Substances

  • Fibroblast Growth Factors