01 February 2026
: Case report 
Subcutaneous Solitary Fibrous Tumor in the Chin of a Young Adult: A Diagnostic Challenge
Challenging differential diagnosis, Rare disease
Gantuya Purevjav ABCF 1, Ai Koyanagi BCDF 2, Balazs Miklos Sandor DEF 3,4, Nyamzaya Molomdalai DF 5, Akinari Kakumoto CDF 2, Tsengelmaa Jamiyan
ACDEF 6*
DOI: 10.12659/AJCR.950318
Am J Case Rep 2026; 27:e950318
Figure 1 Histopathology and immunohistochemical profile of a solitary fibrous tumor (SFT)(A) High-power photomicrograph shows a moderately cellular SFT composed of bland, spindle-shaped cells with scant cytoplasm, arranged in short storiform patterns between collagen bands (hematoxylin and eosin, ×400, scale bar=50 μm). (B) Signal transducer and activator of transcription (STAT)6 shows diffuse nuclear positivity, confirming the SFT diagnosis (immunohistochemistry [IHC], ×400, scale bar=50 μm). (C) Activin receptor-like kinase 1 (ALK1) staining results are negative (IHC, ×400, scale bar=50 μm). (D) MIB-1 demonstrates a low proliferative index of approximately 5% (IHC, ×400, scale bar=50 μm).