RAF1- rearranged Spindle Cell Mesenchymal Tumor With Calcification and Heterotopic Ossification: A Case Report and Review of Literature

Fleur Cordier; Siebe Loontiens; Joni Van der Meulen; Lore Lapeire; Gabrielle H van Ramshorst; Gwen Sys; Jo Van Dorpe; David Creytens

doi:10.1177/10668969231167493

RAF1- rearranged Spindle Cell Mesenchymal Tumor With Calcification and Heterotopic Ossification: A Case Report and Review of Literature

Int J Surg Pathol. 2024 Feb;32(1):133-139. doi: 10.1177/10668969231167493. Epub 2023 May 4.

Authors

Fleur Cordier¹, Siebe Loontiens^{2

3

4}, Joni Van der Meulen^{2

3

4}, Lore Lapeire^{2

5}, Gabrielle H van Ramshorst^{6

7}, Gwen Sys^{2

8}, Jo Van Dorpe^{1

2}, David Creytens^{1

2}

Affiliations

¹ Department of Pathology, Ghent University Hospital, Ghent University, Ghent, Belgium.
² CRIG, Cancer Research Institute Ghent, Ghent University Hospital, Ghent University, Ghent, Belgium.
³ Molecular Diagnostics Ghent University Hospital (MDG), Ghent University Hospital, Ghent University, Ghent, Belgium.
⁴ Department of Biomolecular Medicine, Ghent University, Ghent, Belgium.
⁵ Department of Medical Oncology, Ghent University Hospital, Ghent University, Ghent, Belgium.
⁶ Department of Gastrointestinal Surgery, Ghent University Hospital, Ghent University, Ghent, Belgium.
⁷ Department of Human Structure and Repair, Ghent University, Ghent, Belgium.
⁸ Department of Traumatology and Orthopaedics, Ghent University Hospital, Ghent University, Ghent, Belgium.

PMID: 37141633
DOI: 10.1177/10668969231167493

Abstract

We report an exceptional case of a spindle cell mesenchymal tumor with S100 and CD34 co-reactivity, which harbored a SLMAP::RAF1 fusion. To the best of our knowledge, this is the second case of a spindle cell mesenchymal tumor with S100 and CD34 co-reactivity with this specific fusion. Remarkable is the presence of calcification and heterotopic ossification in the center of our lesion, a feature that, to our knowledge, has not been described yet in RAF1-rearranged spindle cell mesenchymal tumors.

Keywords: NTRK; RAF1; immunohistochemistry; next-generation sequencing; sarcoma; spindle cell tumor.

Publication types

Review
Case Reports

MeSH terms

Biomarkers, Tumor
Choristoma*
Humans
Ossification, Heterotopic* / genetics
Sarcoma* / pathology
Soft Tissue Neoplasms* / complications
Soft Tissue Neoplasms* / genetics
Soft Tissue Neoplasms* / pathology

Substances

Biomarkers, Tumor