The differences in CT findings between schwannoma in mediastinum and retroperitoneum

This study aimed to investigate the differences in computed tomography findings between mediastinal schwannomas and retroperitoneal schwannomas. Consecutive patients diagnosed with mediastinal or retroperitoneal schwannoma at our hospital between November 2006 and February 2022 were retrospectively recruited. Clinical information and preoperative computed tomography images were collected. Histopathology served as the reference standard for diagnosis. Data collected included sex, symptoms, diameters, morphological characteristics, density, hemorrhage, cystic degeneration, calcification, enhancement, and relationships with adjacent structures. Independent t tests, nonparametric tests, and chi-square tests were used as appropriate. Individual matching was used to control the effect of diameter. Seventy-three participants (34 males and 39 females, mean age: 43 ± 14 years) were finally enrolled. The transverse diameter (P = .012), anteroposterior diameter (P = .042), craniocaudal diameter (P < .001), maximum diameter (P = .012), and average diameter (P = .012) of retroperitoneal schwannomas were significantly higher than those of mediastinal schwannomas, leading to more cystic degeneration and displacement of adjacent structures in retroperitoneal schwannomas. After individual matching, mediastinal schwannomas tended to demonstrate oval (85%) while retroperitoneal schwannomas tended to demonstrate rounded (59%) in shape (P < .001). Calcification (33% vs 0%, P = .002) and heterogeneous density (89% vs 52%, P = .008) were more common in retroperitoneal schwannomas than in mediastinal schwannomas. Cystic degeneration and displacement of adjacent structures were more common in retroperitoneal schwannomas due to larger tumor size. Compared with mediastinal schwannomas, retroperitoneal schwannomas tended to be rounded, calcified, and heterogeneous in density.