Virchows Archiv

, Volume 467, Issue 1, pp 119–121 | Cite as

Multifocal cytokeratin expression in pleural and abdominal malignant solitary fibrous tumors: an unusual diagnostic pitfall

  • Evelyne LecoutereEmail author
  • David Creytens
Letter to the Editor

Dear Editor,

Solitary fibrous tumor (SFT) is an uncommon mesenchymal fibroblastic neoplasm usually arising in the pleura, but it can virtually affect any extrapleural site. Conventional SFTs are characterized by short, cytologically bland spindle cells arranged in a patternless architecture, a fibro-collagenous stroma, and a prominent hemangiopericytomatous branching vascular network [1]. The vast majority of SFTs are morphologically and clinically benign. However, 5 to 10 % of SFTs will recur and/or metastasize. Proposed prognostic clinical and morphological criteria for SFT include age at presentation, tumor size, cellularity, mitotic activity (>4 mitoses per 10 high-power fields), the presence of necrosis, and the presence of sharply demarcated anaplastic areas. The vast majority of aggressive SFTs demonstrate these clinical and morphological features of malignancy; however, also morphologically benign-appearing SFTs can metastasize, and therefore, the biological behavior of this...


Solitary Fibrous Tumor Cytokeratin Expression CD34 Reactivity Atypical Spindle Cell Malignant Solitary Fibrous Tumor 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Conflict of interest

The authors declare no conflict of interest.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Department of PathologyGhent University and Ghent University HospitalGhentBelgium

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