Background and purpose: Primary solitary fibrous tumor (SFT) of thyroid is very rare. This study aimed to explore the clinicopathological features and identification of thyroid SFT. Methods: We analyzed one case of primary thyroid SFT treated in Affiliated Hospital of Xuzhou Medical University

including the clinical manifestations

histological features and immunohistochemical phenotypes

and reviewed the relevant English literature. Results: The patient was a 37-year-old male with a well-circumscribed mass in the right lobe of the thyroid gland

and the mass was 3.2 cm in diameter. Microscopically

the tumor displayed proliferation of spindle cells growing in nonspecific “patternless” manner with few amounts of intercellular collagen bundles. The tumor vessels showed branching staghorn-like appearance. Immunohistochemistry showed the spindle cells were positive for signal transducers and activators of transcription 6 (STAT6) (strong

nuclear)

vimentin

CD34

CD99 and Bcl-2 (weak). The patient was followed up for 15 months and in good condition. A total of 25 cases reported in the English literature were followed up for 5-160 months. Only one malignant case had reccurrence and metastasis after 5 months. Conclusion: Thyroid SFT is an uncommon neoplasm

and histopathology and immunohistochemistry can confirm the diagnosis. Most of the tumors are benign with good prognosis. Malignant cases are rare with the risk of recurrence and metastasis. Long-term follow-up is essential to evaluate the prognosis

and surgical resection is the preferred treatment for SFT.