The fat-forming variant of solitary fibrous tumors (SFTs) is a rare soft tissue neoplasm that was previously referred to as a lipomatous hemangiopericytoma (L-HPC). The most common affected site is deep soft tissue. Here, we present the first case, worldwide, of a fat-forming variant of SFT of the pleura. A 74-year-old man presented with left lower chest pain. Chest radiographs showed a mass-like lesion at the left lower lung field and chest computed tomography revealed a 12 cm fat-containing enhancing mass that was well-separated, lobulated and inhomogeneous. Radiology findings suggested a liposarcoma. Percutaneous needle biopsy was performed and pathological diagnosis of the mass was a fat-forming variant of SFT. Surgical resection was carried out and there has been no recurrence to date. So, a benign fat-forming variant of SFT must be considered as one of the differential diagnoses of lipomatous tumors of the pleura.
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