摘要篇首： Fat-forming variant of solitary fibrous tumor (fat-forming variant of SFT), previously called lipomatous hemangiopericytoma (L-HPC), is a recently recognized rare variant of solitary fibrous tumor (SFT)with unpredictable biologic behavior. Fat-forming variant of SFT occurs predominately in the deep soft tissues of the lower extremities. Histologically, it is composed of an admixture of benign hemangiopericytomatous and lipomatous components. Up to now, only 37 cases have been reported in the English literature worldwide1-7 and the molecular analyses are sparse. Reported herein is the first Chinese case of fat-forming variant of SFT. Although one case of fat-forming variant of SFT in the mediastinum was briefly reported, this is the first case in the region with detailed histologic, immunohistochemical features and flow cytometric DNA analysis.