The outcomes of treatment of cauda equina ependymomas in adults

Abstract

Ependymoma is a rare tumor that accounts for about 4% of all central nervous system tumors. Ependymomas typically have intramedullary localization; however, sometimes the tumor is located outside of the spinal cord and affects the cauda equina nerve roots. To study the outcomes of treatment in patients diagnosed with extramedullary ependymoma. Fifty patients (23 males and 27 females) aged 38.7 years (range: 18-76 years) with ependymoma of the cauda equina region were operated on at the 10th Department of the N.N. Burdenko Neurosurgical Institute between January 2009 and December 2013. Thirty-six patients were newly diagnosed with tumors. Fourteen patients were admitted to the N.N. Burdenko Neurosurgical Institute with recurrent or continued tumor growth. The patients were subdivided into two groups according to this criterion. The outcomes of treatment were evaluated using the Frankel, the Karnofsky, and the VAS scales. The criteria proposed by Kawabata et al. were used to assess the long-term outcomes of surgical treatment. Tumor growth was monitored by contrast-enhanced MRI. Tumors were divided into two subtypes: the encapsulated vs. infiltrative forms. Ependymomas were resected subtotally in 5 patients; continued growth of ependymoma was observed in 3 patients. Positive results were obtained for both groups according to the evaluation performed using the scales. According to the criteria of Kawabata et al., the patients were distributed in a following way: in group 1 patients, the good outcome (class 1) was observed in 26 (72%); the fair outcome (class 2), in 8 (22.5%) patients; while the results were equivocal in 2 (5.5%) patients. A number of patients received radiotherapy as a component of combination treatment. Tumor growth stabilization was achieved. Microsurgical intervention is obligatory, since it has a positive effect on the outcomes of surgical treatment of extramedullary intradural tumors, including ependymomas of the cauda equina region. Treatment effectiveness decreases for the infiltrative subtype of tumor growth. Radiation therapy should be used if continued tumor growth is detected or degree of tumor resection was subtotal.