Total removal of cervicothoracic intramedullary 160-mm-long spinal cord ependymoma: a rare case report

Abstract

Ependymomas are neuroectodermal tumours arising from ependymal cells of the ventricular system, choroid plexus, filum terminale, or central canal of the spinal cord. We report on a 160-mm-long cervicothoracic intramedullary spinal cord ependymoma. The tumour was totally removed; no radiotherapy was used as an adjunctive therapy. Postoperative magnetic resonance imaging confirmed that the tumour had been totally removed.

BACKGROUND

Spinal cord ependymomas arise from the ependymal cells lining the central canal. They are the most common intramedullary neoplasms, accounting for 65% of all intramedullary tumours.^1–11 These tumours are well circumscribed, mostly encapsulated and seldom pseudoencapsulated or uncapsulated.^1,2,8–13 They usually show a benign clinical course and slow biological growth with little infiltrative potential and manifest with progressive myelopathy.^3,11 There is no consensus regarding the surgical treatment of this group of tumours. Some authors suggest radical resection,^{1–5,13–15} whereas others propose conservative treatment in association with radiotherapy.^{1–3,5,6,11,13,14} We prefer radical surgical resection in our department. This report describes the case of a patient with acute onset of severe back pain, dysfunction of both legs and urinary incontinence. The case has unusual features, including a 160-mm-long cervicothoracic spinal cord ependymoma. We think this is the first case reported in the English-language literature.^{1–3,6–11,14,15}

CASE PRESENTATION

A 56-year-old man was referred to our hospital with acute onset of severe back pain, dysfunction of both legs and urinary incontinence. Routine laboratory findings were all normal. MRI of the spine revealed a mixed-density intradural mass extending from C4 to T7 (fig 1A).

Figure 1.

MRI of the spine, revealing a mixed-density intradural mass extending from C4 to T7 preoperatively (A) and confirming postoperatively total removal of the tumour (B).

TREATMENT

A C3–T8 laminotomy was performed. The arachnoid membrane was anchored to the incised dura, and the midline of the dorsal surface of the spinal cord was determined by noting vessels penetrating into the dorsal median sulcus. The myelotomy was performed by gently spreading the posterior columns using the operative microscope. The tumour, which was reddish-gray and soft, was identified in the spinal cord after minimal myelotomy around the tumour. The tumour was well demarcated and mostly encapsulated. The vessels feeding the tumour were coagulated by bipolar coagulation. The tumour was totally removed with meticulous dissection. (fig 2). Postoperative MRI confirmed its total removal (fig 1B). Histopathological examination revealed it to be a myxopapillary ependymoma (fig 3).

Figure 2.

Intraoperative image showing cervicothoracic intramedullary 160-mm-long spinal cord ependymoma.

Figure 3.

Neoplastic cells show diffuse growth and perivascular pseudorosettes (H&E; original magnification ×25).

OUTCOME AND FOLLOW-UP

The postoperative course was uneventful and the patient did not develop additional neurological deficit. He was transferred to the rehabilitation unit of our hospital on day 8 after operation. At the 8-week follow-up visit, he was walking without difficulty and his sphincter function had recovered. There has been no tumour recurrence after a follow-up period of 24 months. Adjunctive radiation therapy was not used.

DISCUSSION

Spinal ependymomas are the most commonly occurring intramedullary neoplasms in adults.^{1–3,6–13,15} The vast majority of spinal ependymomas are slowly growing, well demarcated neoplasms with little infiltrative potential. They have been considered to produce a progressive myelopathy by compression of the surrounding spinal cord rather than infiltration into the surrounding neural tissues.^{3–5,9,12,14,15} In addition, they have been recognised as neoplasms that are amenable to complete surgical resection, with acceptable morbidity and mortality and a low incidence of recurrence. However, some cases associated with surgical morbidity have been reported.^4,5,10,14,15 It has been reported that functional results after microsurgical resection of ependymomas are directly related to preoperative neurological status.^{5,7,8,11,13,15} In this case, we wanted to share our experience of a cervicothoracic intramedullary 160-mm-long spinal cord ependymoma.

Intramedullary spinal cord ependymomas have long been recognised as neoplasms that can be totally removed, and long-term remission or cure can be anticipated in many patients.^{3–5,12–15} However, most of the relevant literature antedates the MRI era and there are few large contemporary series that provide an opportunity to analyse the clinical presentation and neurodiagnostic studies as well as the surgical results. We think this is the first case in the English-language literature.^{1–3,6–11,14,15}

Surgical treatment in patients in whom the spinal tumour is diagnosed in early stages on the McCormick scale is helpful to improve the neurological deficits.^6–8,13 Radiotherapy should be reserved for patients who undergo subtotal resection or in whom recurrence is detected. The morbidity of surgery is directly related to the preoperative neurological condition. Patients who are normal or nearly normal preoperatively are rarely worse after surgery, and those who have significant disability preoperatively are at greatest risk of being more impaired after surgery. In our patient, there has been no tumour recurrence after follow-up for 24 months, and radiation therapy has not been used as an adjunctive therapy.

LEARNING POINTS

• Intramedullary ependymomas can be totally resected using a microsurgical technique without causing permanent neurological deficits.

• The most important factor determining the postopoperative neurological status is the preoperative neurological status.

• If the tumour has been removed totally, radiotherapy should be delayed until recurrence is noted.