CT and MRI finding and clinical feature of extrapleural solitary fibrous tumor

Objective To investigate the CT and MRI finding of extrapleural solitary fibrous tumor (ESFT) to improve the preoperative diagnostic ability of such tumors. Methods The clinical data and CT/MRI finding of 11 ESFT patients confirmed by pathology from January 2007 to June 2018 in Jiaxing Traditional Chinese Medicine Hospital Affiliated to Zhejiang Chinese Medicine University were retrospectively analyzed. CT scan was performed in 9 cases and MRI scan in 4 cases. Results Of the 11 patients with ESFT, 6 cases occurred in the abdominal cavity, 3 cases in the cavitas pelvis and 2 cases in the ocular region. All the tumors were solitary, and the maximum diameter of the lesion was (8.3 ± 4.2) cm. The boundary of the tumor was clear in 7 cases, and the boundary was not clear in 4 cases. The tumor form was circular or fusiform in 6 cases and lobulated in 5 cases (some tumors had notch sign). CT scanning presented isodensity or inhomogeneous low density, including 4 cases of cystic degeneration accompanied by inner grid separation, and 3 cases of patchy calcification. The enhanced scanning mass showed 6 cases of geographic enhancement and 7 cases of earthworm drilling soil. MRI T1WI showed slightly lower signal intensity; T2WI fat-suppression sequences showed slightly higher mixed signal intensity in 2 cases and an iso-to high mixed signal intensity in 2 cases; and DWI showed uneven high signal intensity in 3 cases. The solid part of the enhanced scanning showed' fast enhancement and slow washout'. Conclusions ESFT is usually manifested as isolated mass, and its CT and MRI finding has certain characteristics, especially in the diagnosis and differential diagnosis of the disease, such as geographic enhancement and earthworm drilling soil signs. Key words: Solitary fibrous tumors; Tomography, spiral computed; Magnetic resonance imaging; Retrospective studies