ABSTRACT
【Objective】 To investigate the clinicopathological characteristics and prognosis of solitary fibrous tumor (SFT) in the retroperitoneum. 【Methods】 We summarized the clinical and prognostic data of nine patients admitted to The First Affiliated Hospital of Xi’an Jiaotong University between January 2007 and December 2017 who were diagnosed with SFT by surgical resection and pathological examination. Nine cases of retroperitoneal SFT were detected by HE and immunohistochemical SP method. The expressions of Vimintin (Vim), CD34, CD99, Ki-67, Bcl-2 and S-100 in tumor cells were analyzed for their clinicopathological characteristics and prognosis. 【Results】 Among the nine patients, four were male and five were female, aged 37-69 years old. Five of them showed abdominal distension, while the other four had no obvious clinical symptoms. The tumor size was (1.0 cm×1.0 cm×2.0 cm)-(30.0 cm×25.0 cm×10.0 cm). There were seven single cases and two multiple cases. Histology showed bundle-shaped, braided spindle cells and collagen fibers of varying degrees, accompanied by mucinous degeneration and hemangiopericytoma-like morphology. Immunohistochemical results were as follows: The positive rate was 100% (9/9) for Vim, CD34 and CD99, 77% (7/9) for Ki-67, 67% (6/9) for Bcl-2, and 22% (2/9) for S-100. All the patients were followed up effectively. Two of them died (the cause of death was not related to the disease studied, and the survival time from postoperative to death was 6.5 years and 8.3 years, respectively). One surviving case relapsed 3 years after the operation, but did not recur after the second operation. No recurrence or metastasis was found in the remaining cases. 【Conclusion】 Retroperitoneal SFT is rare in the clinic, and there are no typical clinical symptoms in the early stage. Most of them are detected in physical check-ups. Ultrasound and CT examinations are the main preoperative examination methods, but they are not specific to SFT. Pathological examination is the only method for diagnosis. Radical resection is the first-choice of treatment. The preferred method for this disease is effective in early radical surgery and regular postoperative review.