Giant Invasive Sacral Schwannoma with Aortic Bifurcation Compression and Hydronephrosis.

Abstract

Sacral schwannomas are rare tumors arising from nerve sheath Schwann cells. They are classified into 3 types: first type schwannoma arising from the sacrum, second type schwannoma eroding the sacrum, and third type schwannoma extending extensively, involving anterior, posterior, and retroperitoneal space. Among these type 2 sacral tumors, according to Klimo's classification, an eroding sacrum extending all over posteriorly, anteriorly, and laterally is still rarer. Only 38 cases have been reported in literature reviews. Only 6 cases of giant tumors of >10 cm in any 1 dimension have been reported. We present such a giant sacral schwannoma, with invasiveness eroding the sacrum; compressing the ureters, aortic bifurcation, bladder, and bowel; and presenting as lower abdominal pain, hydronephrosis, dysuria, and constipation. This is the first case reported in the literature that has described a large retroperitoneal tumor compressing retroperitoneal structures-aortic bifurcation vascular compression and ureter compression causing hydronephrosis. Though complete resection, which caused various severe postoperative complications in the reported cases, is the best option, a less morbid procedure would be appropriate; hence we underwent subtotal excision of the tumor, with complete recovery of our patient's symptoms without neurologic deficit.