Abstract
We report a case of a pelvic schwannoma.
A 72-year-old man was admitted because of melena. Ultrasonography revealed a well-defined cystic tumor located in the pelvis. CT scan showed a well-defined tumor, 6 cm in diameter, which had calcifications and was located in the presacral space. The tumor showed mixed intensity on T1 and T2-weighted MRI images. An operation was done. The tumor was removed. The tumor was found to be very adherent to the anterior surface of the sacral bone, it was nevertheless removed. The resected tumor measured 6 × 5.5 × 5 cm and had multiple cysts filled with serous fluid. On histopathology, the tumor was found to be composed of spindle-shaped cells without nuclear-atypia that were positive for S-100 protein. Thus, a benign ancient schwannoma was diagnosed.
Pelvic schwannoma is relatively rare and difficult to diagnose preoperatively due to a lack of specific subjective symptoms and specific imaging findings. Since excision of the tumor can result in a neurological disorder patients must be informed of this risk prior to surgery.
