A case of dedifferentiated solitary fibrous tumor in the pelvis with TP53 mutation

作者：Kurisaki Arakawa Aiko; Akaike Keisuke; Hara Kieko; Arakawa Atsushi; Takahashi Michiko; Mitani Keiko; Yao Takashi; Saito Tsuyoshi^*

来源：Virchows Archiv, 2014, 465(5): 615-621.

DOI：10.1007/s00428-014-1625-3

• Solitary fibrous tumor
• STAT6
• NAB2-STAT6
• Dedifferentiation

Solitary fibrous tumors (SFTs), initially observed in the pleura, were later found to develop in almost any extrapleural site. Dedifferentiation within SFTs was characterized only recently. We report a case of dedifferentiated SFT arising within the pelvis of a 70-year-old Japanese woman. Macroscopically, the resected tumor measured 17 x 17 x 13 cm. Histologically, the tumor displayed distinct heterologous osteosarcomatous and chondrosarcomatous components on a background of conventional SFT. Immunohistochemistry uncovered a loss of CD34 expression in the dedifferentiated area, whereas the nuclear expression of signal transducer and activator of transcription-6 (STAT6) and NGFI-A-binding protein 2 (NAB2) was maintained in both components. The p53 mutation 158 CGC %26gt; CAC (A158H) was found only in the dedifferentiated component. Furthermore, a fusion gene of NAB2(exon6)-STAT6(exon18) was detected in both the conventional and dedifferentiated components. The patient died of the disease 4 months after surgery. This case identifies a possible role of p53 dysfunction in the dedifferentiation process of SFT as reported in other sarcomas.

• 出版日期2014-11