Özet:

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms. These tumors were first described in 1931 by Klemperer and Rabin. Although SFTs are usually located in the thoracic cavity and pleura, they have been reported in numerous other extrathoracic sites. Nearly 85 to 90% of SFTs are benign. With the increasing use of fine needle aspiration (FNA) cytology in diagnosis, which is a less invasive technique than biopsy, we encounter with cytological smears of these tumors more frequently. Herein, we report a rare case of malignant SFT with relevant cytological findings and differential diagnosis in the light of literature data. 66-year-old male patient was admitted to the gastroenterology outpatient clinic in our center with dyspnea and feeling of abdominal fullness in right upper quadrant. We performed FNA biopsy from the heterogeneous lesion located in the inferior surface of the liver (25x20 cm in size) using 22-gauge needle under the guidance of endoscopic ultrasonography (EUS). Slides derived from the cell block showed spindle/oval-shaped cells with a scanty cytoplasm and a patternless arrangement in the collagenized stromal fragments with a few number of inflammatory cells. Immunohistochemical (IHC) studies using tissue samples demonstrated vimentin and CD34 diffuse positivity, positive pale Bcl-2 staining, smooth muscle actin, desmin, S100, CD117, DOG1, factor 8 and pancytokeratin negativity. Based on these findings, the patient was diagnosed with a SFT of mesenchymal origin. Due to the limited number of data regarding cytological findings of malignant SFTs, our case report contributes to the ongoing body of literature.

Anahtar Kelimeler: