====== Spinal schwannoma recurrence ======

[[Spinal schwannoma]] [[recurrence]] is rare after total [[excision]] (except in [[neurofibromatosis]]).
As schwannoma is a benign well encapsulated tumor, complete removal is expected from surgery. Recurrence is expected in cases of NF, but usually at a site different from previous site. In case of large dumbbell tumors if residual tumor is left recurrence can occur
((Seppälä MT, Haltia MJ, Sankila RJ, Jääskeläinen JE, Heiskanen O. Long-term outcome after removal of spinal schwannoma: a clinicopathological study of 187 cases. J Neurosurg. 1995 Oct;83(4):621-6. doi: 10.3171/jns.1995.83.4.0621. PMID: 7674010.)).

Recurrence of conventional spinal schwannomas is reported in less than 5% of surgical patients. Tumor recurrence typically occurs several years after initial surgical resection and appears to be associated with subtotal tumor removal
((Traul DE, Shaffrey ME, Schiff D. Part I: spinal-cord neoplasms-intradural neoplasms. Lancet Oncol. 2007 Jan;8(1):35-45. doi: 10.1016/S1470-2045(06)71009-9. PMID: 17196509.))
((Schick U, Marquardt G, Lorenz R. Recurrence of benign spinal neoplasms. Neurosurg Rev. 2001 Mar;24(1):20-5. doi: 10.1007/pl00011961. PMID: 11339463.))
((Liu JX, Zhou HZ, Yang SH, Shao ZW, Zheng QX, Yang C, Gao Y, Raj S, Mohan DR. Clinical analysis of 73 cases of intraspinal nerve sheath tumor. J Huazhong Univ Sci Technolog Med Sci. 2013 Apr;33(2):258-261. doi: 10.1007/s11596-013-1107-x. Epub 2013 Apr 17. PMID: 23592140.)).

Although several surgical series have discussed recurrence, very few have reported on risk factors for the recurrence of conventional spinal schwannomas located throughout different spinal segments
((Fehlings MG, Nater A, Zamorano JJ, Tetreault LA, Varga PP, Gokaslan ZL, Boriani S, Fisher CG, Rhines L, Bettegowda C, Kawahara N, Chou D. Risk Factors for Recurrence of Surgically Treated Conventional Spinal Schwannomas: Analysis of 169 Patients From a Multicenter International Database. Spine (Phila Pa 1976). 2016 Mar;41(5):390-8. doi: 10.1097/BRS.0000000000001232. PMID: 26555828; PMCID: PMC4769652.)).

The rates of tumor recurrence following surgical resection have been reported as 4 to 6% in previous surgical series
((Seppälä MT, Haltia MJ, Sankila RJ, Jääskeläinen JE, Heiskanen O. Long-term outcome after removal of spinal schwannoma: a clinicopathological study of 187 cases. J Neurosurg. 1995 Oct;83(4):621-6. doi: 10.3171/jns.1995.83.4.0621. PMID: 7674010.))
((Conti P, Pansini G, Mouchaty H, Capuano C, Conti R. Spinal neurinomas: retrospective analysis and long-term outcome of 179 consecutively operated cases and review of the literature. Surg Neurol. 2004 Jan;61(1):34-43; discussion 44. doi: 10.1016/s0090-3019(03)00537-8. PMID: 14706374.))
((Safavi-Abbasi S, Senoglu M, Theodore N, Workman RK, Gharabaghi A, Feiz-Erfan I, Spetzler RF, Sonntag VK. Microsurgical management of spinal schwannomas: evaluation of 128 cases. J Neurosurg Spine. 2008 Jul;9(1):40-7. doi: 10.3171/SPI/2008/9/7/040. PMID: 18590409.)).

In the study of Fehlings et al., the rate of [[recurrence]] was 5.32% and patients with [[tumor recurrence]] tended to be younger. Most conventional [[spinal schwannoma]]s occurred in the [[lumbar spine]]; however, when location of the initial lesion was examined, there was a greater recurrence in cervical and sacral segments. In fact, two out of fifteen (13.33%) cervical and two out of twenty sacral schwannomas recurred whereas only five out of 70 (7.14%) patients with a lumbar tumor experienced recurrence. In addition, univariate analyses showed that the major predictors of recurrence were an increased number of vertebral levels, larger overall tumor size, a greater measurement in the cranial-caudal direction, and an intralesional resection
((Fehlings MG, Nater A, Zamorano JJ, Tetreault LA, Varga PP, Gokaslan ZL, Boriani S, Fisher CG, Rhines L, Bettegowda C, Kawahara N, Chou D. Risk Factors for Recurrence of Surgically Treated Conventional Spinal Schwannomas: Analysis of 169 Patients From a Multicenter International Database. Spine (Phila Pa 1976). 2016 Mar;41(5):390-8. doi: 10.1097/BRS.0000000000001232. PMID: 26555828; PMCID: PMC4769652.)).