Imaging features and preoperative diagnostic insights of esophageal schwannomas as a rare type

We aimed to analyze and summarize the key features of esophageal schwannomas to provide new insights into preoperative diagnosis and enhance clinical recognition.

Twenty-one consecutive patients with pathologically confirmed esophageal schwannoma who underwent surgical resection between January 2013 and January 2023 were enrolled. Imaging results from barium swallow, CT, MRI, ¹⁸F-FDG PET-CT, esophagoscopy, and endoscopic ultrasound were compiled and analyzed.

Our cohort comprised 10 males and 11 females, with mean age of 55.86 ± 9.09 years. The mean tumor size was 5.69 ± 1.32 cm, with tumors commonly located in the upper to middle esophagus. 83.3 % (10/12) presented smooth filling defects with intact canal walls in barium meal. Most tumors (71.4 %, 15/21) were oval-shaped, exhibiting intracavitary growth with well-defined borders. Mild enhancement was observed on CT with pre-contrast attenuation of 36.0 ± 53.87 HU and post-contrast enhancement of 52.75 ± 7.45 HU. Most lesions showed plateau dynamic enhancement on MRI (85.7 %, 6/7). Air crescent signs (95.2 %, 20/21) and fascicular signs (87.5 %, 7/8) were observed in most cases. Neither calcifications nor target signs were observed, and cystic changes were infrequent. All lesions showed high uptake on PET-CT (SUVmax: 11.19 ± 3.41). Endoscopic lesions typically exhibit smooth surfaces, soft textures, and colors ranging from normal to slightly lighter hues (94.7 %, 18/19). Endoscopic ultrasound indicated minimal blood flow within lesions (53.8 %, 7/13), and elastography displayed a blue-green pattern (100 %, 5/5).

Esophageal schwannomas exhibit distinct imaging characteristics. MRI provides additional diagnostic information for more accurate evaluation, while high metabolic activity on PET-CT may mimic malignancy.