Myxopapillary ependymoma
Updates to Article Attributes
Spinal myxopapillary ependymomas are a variant type of spinal ependymoma that occur almost exclusively in the conus medullaris and filum terminale. They represent 13% of all spinal ependymomas,and are by far the most common tumours of the conus medullaris and filum terminale.
Epidemiology
They tend to have an earlier clinical presentation than other spinal ependymomas, with a mean age of presentation of 35 years. There is a slight male predominance.
Clinical presentation
The most common presenting symptoms are low back, leg or sacral pain. Up to 25% of patients may present with leg weakness or sphincter dysfunction.
They may occasionally present as a subarachnoid haemorrhage 8.
Pathology
They are thought to arise from the ependymal glia of the filum terminale or conus medullaris. The vast majority are intradural and extramedullary, however, rarely they occur in the extradural space. They are generally classified as WHO grade I lesions, however, occasionally CSF dissemination occurs and multiple lesions are seen in 14-43% cases 4. In children, these tumours may have more aggressive behaviour 9.
Macroscopic appearance
They are typically multilobulated and encapsulated. They often have associated haemorrhage, and may calcify or undergo cystic degeneration9.
Microscopic appearance
Histologically, they contain papillary elements inarranged radially around a myxoid backgroundhyalinized fibrovascular core, admixedforming perivascular pseudorosettes, with ependymoma-likemyxoid material between the blood vessel and tumour cells9. "Balloons" - rounded eosinophilic PAS positive structures - are sometimes encountered 9.
Immunophenotype
As is the case with ependymomas generally, myxopapillary ependymomas are GFAP, S100 and vimentin positive 9. CD99, AE1/AE3 and NCAM1 are also commonly positive 9.
Radiographic features
Plain radiograph / CT
If they become large, myxopapillary ependymomas may expand the spinal canal, cause scalloping of the vertebral bodies and extend out of the neural exit foramina.
MRI
Smaller tumours tend to displace the nerve roots of the cauda equina; larger tumours often compress or encase them 8.
Signal characteristics
-
T1
- usually isointense
- prominent mucinous component occasionally results in T1 hyperintensity
- haemorrhage and calcification can also lead to regions of hyper- or hypointensity
-
T2
- overall high intensity
- low intensity may be seen at the tumour margins because of haemorrhage (myxopapillary ependymomas are the subtype of ependymomas that are most prone to haemorrhage 8)
- calcification may also lead to regions of low T2 signal
-
T1 C+ (Gd)
- enhancement is virtually always seen
- the enhancement pattern is typically homogeneous, however they can have a variable enhancement pattern that, in part, depends on the amount of haemorrhage present
Treatment and prognosis
Myxopapillary ependymomas are generally slow-growing, although some sacral and presacral lesions behave aggressively and metastasise to lymph nodes, lung and bone. This is particularly the case in children 9.
They can often be excised completely. In these cases, the prognosis is excellent, with 5-year-survival over 98% 9.
If the tumour has extended into the subarachnoid space and surrounded the roots of the cauda equina, resection is often incomplete and local recurrence is likely.
Differential diagnosis
Differential diagnosis of a small conus and filum terminale myxopapillary ependymoma includes:
- spinal schwannoma: often indistinguishable from ependymoma
- spinal paraganglioma
Differential diagnosis of a large myxopapillary ependymoma that causes sacral destruction:
- aneurysmal bone cyst: involving the spine
- chordoma
- giant cell tumour: involving the spine
See also
-<p><strong>Spinal myxopapillary ependymomas</strong> are a variant type of <a href="/articles/spinal-ependymoma">spinal ependymoma</a> that occur exclusively in the conus medullaris and filum terminale. They represent 13% of all spinal ependymomas,<sup> </sup>and are by far the most common tumours of the <a title="Conus medullaris" href="/articles/conus-medullaris">conus medullaris</a> and <a title="Filum terminale" href="/articles/filum-terminale">filum terminale</a>. </p><h4>Epidemiology</h4><p>They tend to have an earlier clinical presentation than other spinal ependymomas, with a mean age of presentation of 35 years. There is a slight male predominance.</p><h4>Clinical presentation</h4><p>The most common presenting symptoms are low back, leg or sacral pain. Up to 25% of patients may present with leg weakness or sphincter dysfunction.</p><p>They may occasionally present as a <a title="Subarachnoid haemorrhage" href="/articles/subarachnoid-haemorrhage">subarachnoid haemorrhage</a> <sup>8</sup>.</p><h4>Pathology</h4><p>They are thought to arise from the ependymal glia of the filum terminale or conus medullaris. The vast majority are intradural and extramedullary, however, rarely they occur in the extradural space. They are generally classified as WHO grade I lesions, however occasionally CSF dissemination occurs and multiple lesions are seen in 14-43% cases <sup>4</sup>.</p><h5>Macroscopic appearance</h5><p>They are typically multilobulated and encapsulated. They often have associated haemorrhage, and may calcify or undergo cystic degeneration.</p><h5>Microscopic appearance</h5><p>Histologically, they contain papillary elements in a myxoid background, admixed with ependymoma-like cells.</p><h4>Radiographic features</h4><h5>Plain radiograph / CT</h5><p>If they become large, myxopapillary ependymomas may expand the spinal canal, cause scalloping of the vertebral bodies and extend out of the neural exit foramina.</p><h5>MRI</h5><p>Smaller tumours tend to displace the nerve roots of the cauda equina; larger tumours often compress or encase them <sup>8</sup>.</p><h6>Signal characteristics</h6><ul>- +<p><strong>Spinal myxopapillary ependymomas</strong> are a variant type of <a href="/articles/spinal-ependymoma">spinal ependymoma</a> that occur almost exclusively in the conus medullaris and filum terminale. They represent 13% of all spinal ependymomas,<sup> </sup>and are by far the most common tumours of the <a href="/articles/conus-medullaris">conus medullaris</a> and <a href="/articles/filum-terminale">filum terminale</a>. </p><h4>Epidemiology</h4><p>They tend to have an earlier clinical presentation than other spinal ependymomas, with a mean age of presentation of 35 years. There is a slight male predominance.</p><h4>Clinical presentation</h4><p>The most common presenting symptoms are low back, leg or sacral pain. Up to 25% of patients may present with leg weakness or sphincter dysfunction.</p><p>They may occasionally present as a <a href="/articles/subarachnoid-haemorrhage">subarachnoid haemorrhage</a> <sup>8</sup>.</p><h4>Pathology</h4><p>They are thought to arise from the ependymal glia of the filum terminale or conus medullaris. The vast majority are intradural and extramedullary, however, rarely they occur in the extradural space. They are generally classified as WHO grade I lesions, however, occasionally CSF dissemination occurs and multiple lesions are seen in 14-43% cases <sup>4</sup>. In children, these tumours may have more aggressive behaviour <sup>9</sup>. </p><h5>Macroscopic appearance</h5><p>They are typically multilobulated and encapsulated. They often have associated haemorrhage and may calcify or undergo cystic degeneration <sup>9</sup>.</p><h5>Microscopic appearance</h5><p>Histologically, they contain papillary elements arranged radially around a hyalinized fibrovascular core, forming <a title="Perivascular pseudorosettes" href="/articles/perivascular-pseudorosettes-ependymoma">perivascular pseudorosettes</a>, with myxoid material between the blood vessel and tumour cells <sup>9</sup>. "Balloons" - rounded eosinophilic PAS positive structures - are sometimes encountered <sup>9</sup>. </p><h5>Immunophenotype</h5><p>As is the case with ependymomas generally, myxopapillary ependymomas are <a href="/articles/glial-fibrillary-acid-protein-gfap">GFAP</a>, <a href="/articles/s100">S100</a> and <a href="/articles/vimentin">vimentin</a> positive <sup>9</sup>. CD99, AE1/AE3 and NCAM1 are also commonly positive <sup>9</sup>. </p><h4>Radiographic features</h4><h5>Plain radiograph / CT</h5><p>If they become large, myxopapillary ependymomas may expand the spinal canal, cause scalloping of the vertebral bodies and extend out of the neural exit foramina.</p><h5>MRI</h5><p>Smaller tumours tend to displace the nerve roots of the cauda equina; larger tumours often compress or encase them <sup>8</sup>.</p><h6>Signal characteristics</h6><ul>
-</ul><h4>Treatment and prognosis</h4><p>Myxopapillary ependymomas are generally slow-growing, although some sacral and presacral lesions behave aggressively and metastasise to lymph nodes, lung and bone.</p><p>They can often be excised completely. In these cases, prognosis is excellent. If the tumour has extended into the <a title="Subarachnoid space" href="/articles/subarachnoid-space">subarachnoid space</a> and surrounded the roots of the cauda equina, resection is often incomplete and local recurrence is likely.</p><h4>Differential diagnosis</h4><p>Differential diagnosis of a small conus and filum terminale myxopapillary ependymoma includes:</p><ul>- +</ul><h4>Treatment and prognosis</h4><p>Myxopapillary ependymomas are generally slow-growing, although some sacral and presacral lesions behave aggressively and metastasise to lymph nodes, lung and bone. This is particularly the case in children <sup>9</sup>. </p><p>They can often be excised completely. In these cases, the prognosis is excellent, with 5-year-survival over 98% <sup>9</sup>.</p><p>If the tumour has extended into the <a href="/articles/subarachnoid-space">subarachnoid space</a> and surrounded the roots of the cauda equina, resection is often incomplete and local recurrence is likely.</p><h4>Differential diagnosis</h4><p>Differential diagnosis of a small conus and filum terminale myxopapillary ependymoma includes:</p><ul>
-</ul><h4>See also</h4><ul><li><a href="/articles/intradural-spinal-mass-lesions-an-approach">intradural spinal mass lesions-an approach</a></li></ul>- +</ul><h4>See also</h4><ul><li><a href="/articles/intradural-spinal-mass-lesions-an-approach-1">intradural spinal mass lesions-an approach</a></li></ul>
References changed:
- 9. Louis DN, Ohgaki H, Wiestler OD et-al. "WHO Classification of Tumours of the Central Nervous System. 4th Edition Revised" <a href="https://books.google.co.uk/books?vid=ISBN9789283244929">ISBN: 9789283244929</a><span class="ref_v4"></span>
Unable to process the form. Check for errors and try again.