A giant pelvic malignant schwannoma: a case report and literature review.

Schwannomas are usually benign tumors that arise from well-differentiated Schwann cells. They rarely occur in the retroperitoneum. Here, we present a case of a 60-year-old man with a giant retroperitoneal pelvic mass. Imageological diagnosis suggested a large heterogeneous mass of 16 cm in diameter located in the abdominopelvic retroperitoneum. Complete intralesional enucleation was achieved without any adjacent organs injury except a severe bleeding which was ceased as we applied the bilateral inferior vesical artery embolization. Final histopathological result showed the tumor was a low malignant Schwannoma. The patient's symptoms were greatly improved after operation. Unfortunately, a local recurrence was detected at the six-month follow-up appointment with consequent losing to follow up.