Clinicopathologic analysis of solitary fibrous tumor of kidney

Objective To explore the clinical pathological features,diagnosis and differential diagnoses of solitary fibrous tumor (SFT) of the kidney. Methods A case of SFT of the kidney was examined with light microscopy and immunohistochemistry, and related literature was reviewed. Results The patient was 47 year old woman. Clinical and radiological examination revealed a tumor in the renal pelvis suspected carcinoma of renal pelvis. Grossly, the tumor was well-circumscribed with grey white color on cut surface. Microscopically, the tumor was composed of bland spindle-shaped cells and dense collagenous bands, with fascicular, storiform,or haphazard arrangements. Focal areas showed a haemangiopericytoma-like structure. The cells had no obviously atypical. Mitoses were seen occasionally. Immunohistochemically, the tumor cells were positive for vimentin, CD34, CD99, partially positive for Bcl-2, and negative for desmin, SMA, MSA, carponin, HMB45, CD117, S-100 protein,CD31,FVIII,CK (AE1/AE3), and EMA. Conclusions SFT of the kidney is a very rare spindle-cell neoplasm. Diagnonsis is based on its morphology and immunohistochemistry. Differential diagnosis includes other spindle-shaped cell tumors of the kidney.