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Objective. To assess the significance of clinical factors of extramedullary tumors and new methods of their resection as potential predictors of their recurrence and continued growth.Material and Methods. The long-term results of removal of primary extramedullary tumors in 412 patients operated on in 1998–2014 were analyzed comparing the use of standard methods of microsurgical technique for tumor removal (277 patients) and of those with additional use of neodymium laser radiation (135 patients).Results. The use of laser technologies for resection of extramedullary tumors can significantly reduce the number of their recurrences and continued growth, along with other clinical factors is a significant prognostic indicator in determining the nature of the disease course and can be a predictor of their occurrence. The most reliable clinical factors determining the prognosis of a decrease in the incidence of recurrences and continued growth when using laser techniques of surgical resection were repeated operations (p = 0.002), the presence of ependymomas of the cone and cauda equina (p = 0.017), operations for primary tumors in the thoracic spine (p = 0.039) and extramedullary tumors with Grade I anaplasia (p = 0.007). An increase in the number of these conditions was associated with operations on the cervical spine (p = 0.027), the presence of a tumor with Grade II anaplasia (p = 0.007), and a primary extramedullary tumor involving more than three vertebrae (p = 0.017).Conclusion. The use of the laser is indicated for reoperations when removing neoplasms, that have arisen as a result of recurrence or continued growth of extramedullary tumors of any level and length after removal of primary neoplasms with a Grade I malignancy confirmed by intraoperative cytological examination involving no more than three vertebrae in the thoracic, lumbar and sacral spine and during resection of ependymomas with extramedullary growth.

Objective. To assess the effect of neodymium laser radiation on the recurrence rate and continued growth of primary extramedullary tumors on the basis of clinical data obtained in the long-term follow-up period in operated patients with extramedullary tumors.Material and Methods. The long-term results of surgical treatment of two groups of patients (n = 412) with primary extramedullary tumors operated on from 1998 to 2014 were studied and systematized. Patients of comparison group (n = 277; 67.2 %) underwent removal of tumors using standard microsurgical techniques, and the neoplasms in patients of the study group (n = 135; 32.8 %) were removed with additionally used neodymium (Nd:YAG) laser.Results. The use of the developed laser technologies for the resection of extramedullary intracanal primary tumors made it possible to reliably reduce the relative number of recurrence and continued growth from 11.1 % to 1.2% compared with patients treated with standard surgery methods. The proportion of recurrences was 3.5 %, all of them were detected only in the group with the classical technique of tumor resection (p <0.01).Conclusion. The use of a neodymium laser as an additional technology to the classical microsurgical resection of extramedullary tumors is effective for the prevention of their recurrence and continued growth.

Objective. To analyze clinical and morphological features of neurogenic hourglass tumors in the thoracic spine and their impact on outcomes of treatment through posterior surgical approaches.Material and Methods. The results of surgical treatment of 295 patients with tumors growing from the nerve roots of the thoracic spinal cord were studied. In 63 (21 %) of them, tumors of the spinal nerves were diagnosed. The vast majority of neoplasms were represented by Grade 1 neuromas – in 57 (90 %) patients, Grade 1 neurofibromas were found in 3 (5 %) patients, and High-grade malignant tumors – in 3 (5 %). Intracanal neoplasms were found in 42 (66.7 %) cases and intraextravertebral (hourglass) – in 21 (33.3 %).Results. Microsurgical removal of tumor was performed using two types of low-traumatic surgical approaches: 1) posterior median approach – in 56 (89.0 %) cases, of which hemilaminectomy was performed in 36 (64.4%) cases, interlaminectomy – in 15 (26.8 %) cases, and laminectomy – in 5 (8.1 %) cases; 2) paravertebral approach – in 7 (11.0 %) out of 63 cases with partial facetotomy or facetectomy and resection of part of the head and upper or lower edge of the rib at the same level. Tumors were removed totally in 56 (88.9 %) patients and subtotally – in 7 (11.1%). Intracanal tumors were removed totally in 40 (95.2 %) patients. A similar totality was achieved in removal of 16 (76.2 %) of hourglass neurinomas. Surgical interventions performed in the early postoperative period improved the functional state of  patients: the Karnofsky Performance Scale (KPS) index increased from 70–80 to 90 %, the VAS pain score decreased from 5–6 to 2 points. Good clinical outcomes were achieved in 42 (66.7 %) patients, satisfactory – in 17 (27.0 %), and unsatisfactory – in 6 (6.3 %). Twenty nine patients had symptoms of myelopathy, complete regression of which occurred in 3 (10.3 %) cases, partial – in 9 (34.6 %), in 13 (50.0 %) cases they remained at the preoperative level, and in 4 (15.4 %) – worsened.Conclusion. The use of modern neurointroscopy, microsurgical techniques and low-traumatic posterior surgical approaches for resection of tumors of the spinal nerve roots in the thoracic spine provides good clinical outcomes of treatment in the early postoperative period. The existing hourglass tumor in the thoracic spine reduces the likelihood of its total removal when performing a low-traumatic posterior approach.