Complete removal of the spinal nerve sheath tumors. Surgical technics and results from a series of 30 patients

Abstract

Objective: Observe whether a microsurgical gross total removal (GTR) of a spinal nerve sheath tumors (SNSTs) is safe and decreases the tumor recurrence. Method: We identify 30 patients with 44 SNSTs. Results: We operated upon 15 males and 15 females patients; mean age 40 years. GTR was achieved in 29 (96.6%) instances. Surgical mortality was 3.3% and the recurrence rate was 3.3%. The median follow-up time was 6.2 years. Conclusion: The surgical approach used in this group of patients afford that the great majority of tumors could be totally removed with low mortality and low recurrence rates, proving to be safe and effective.Keywords: microsurgery, neurofibroma, schwannoma, spinal nerve sheath tumors, surgical treatment. RESUMOObjetivo: Observar se a ressecção microcirúrgica completa dos shwannomas ou neurofibromas raquianos é uma técnica segura e efetiva. Método: Foram operados 30 pacientes com 44 schwannomas ou neurofibromas intrarraquiano. Resultados: A remoção total da lesão ocorreu em 27 casos (96.6%). A taxa de mortalidade cirúrgica observada nesta série foi de 3.3%. O tempo médio de seguimento foi de 6.2 anos. Conclusão: A estratégia microcirúrgica empregada com esses pacientes propiciou a remoção total dos tumores na maioria dos pacientes, com baixa mortalidade e recidiva tumoral, mostrando ser segura e efetiva.Palavras-chave: microcirurgia, neoplasia raquiana, neurofibroma, tumors da bainha dos nervos, schwannoma raquiano.The annual incidence rates for primary spinal neoplasms are reported to be in the range of 1.3 to 10.0 per 100,000 1 . One-third is nerve sheet tumors 1,2,3 . The spinal nerve sheet tumors (SNSTs) comprise the schwannomas and neurofibromas 1,2,3,4 . Nevertheless little attention has been paid to this subject within Brazilian settings, which motivated us to review and present the cases of this pathological condition treated by our medical team, and to assess the safety and efficiency of microsurgical removal of those lesions.Various terms have been used for this tumor: neuroma, neurinoma, neurilemoma, perineurial fibroblastoma, schwannoma gliome peripherique, schwannoma and neurofibroma 2,4 . The SNSTs are benign, usually solitary, slowgrowing, encapsulated neoplasms composed of differentiated neoplastic Schwann cells. The most common origin of these tumors is the posterior spinal nerve root 1,2,3,4,5,6 . METHOD Data collectionThe 30 patients registered in this retrospective study with SNSTs were operated at the Hospital Federal dos Servidores do Estado (RJ) and at Rede D'Or São Luiz between 1986 and 2012. The medical charts, pre and postoperative imaging, and pathological reports were retrospectively reviewed for each patient to confirm the diagnosis of SNSTs; creating a database from which information pertinent to the present study was collected. The intraoperative videos of 11 patients were analyzed for nuances of the microsurgical technique. The need for informed consent was waived due to the retrospective character of the study. Detailed neurological examinations were perfo...

Association of tumor location, extent of resection, and neurofibromatosis status with clinical outcomes for 221 spinal nerve sheath tumors

“…For previous surgical series, recurrence rates of 1.9%-5.8% and GTR rates of 85%-97% have been reported. 4,7,9,12,15,[20][21][22] However, many of these studies are characterized by higher numbers of schwannomas than neurofibromas. The likely explanation for the higher recurrence rates in our study is the higher number of spinal neurofibromas (53) and higher percentage of cervical nerve sheath tumors (38%) than are typically reported in the literature.…”

“…4,7,9,12,15,[20][21][22] These contributions are valuable but limited by sample size and age of data sets. We sought to characterize our institutional experience with the management of these lesions, focusing on patient demographics, history of NF, clinical presentation, and factors associated with extent of resection and tumor recurrence.…”

Median nerve schwannoma

“…Thus, schwannomas often initially present as a palpable mass, as noted in the present case. Radiological examinations reveal schwannomas as round or oval, located close to the nerve tissue, encapsulated, isolated and non‐invasive . Although NFs show similar radiological findings, NFs are nonencapsulated and invasively grow into the surrounding nerves .…”

“…Schwannoma, also known as neurilemmoma/neurinoma, is a benign true‐capsuled tumour derived from the peripheral nerve sheath . Schwannomas are usually palpable, painless and solitary lesions . These tumours most frequently appear between 20 and 50 years of age, with similar incidence rates in males and females .…”

“…Schwannoma and neurofibroma (NF) are two distinct types of peripheral nerve sheath tumour, of which schwannoma is the most common type (1%), accounting for 5% of all tumours in the upper extremity and 0.1–0.3% of all hand tumours . The ulnar and peroneal nerves are most frequently involved, whereas only 7% of schwannomas occur in the median nerve .…”