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astrocytes supply structural support of the central nervous system whereas ependymal cells line the ventricular system .
myxopapillary ependymoma ( mpe ) is a subtype of ependymoma , which is exclusively observed at conus smedullaris , cauda equina , and filum terminale17 ) .
concomitant double tumor presentation of mpe at conuscauda - filum level is very rare . to date , 10 cases have been presented28910161721 ) . herein , we report a new case of mpe presented as double tumor in noncontiguous segments of lumbosacral spinal column .
a 32-year - old man presented with gradually increasing bilateral buttock pain for the last 3 months .
magnetic resonance imaging showed multiple intradural extramedullary lesions with homogenous enhancement at l2-l3 and l5-s1 levels ( fig .
whole cranium and spine were searched for any other tumors , yet no other one could be observed except the ones we have already detected at the lumbosacral region .
the lesions were completely encapsulated by thin fibrous capsules with a well - delimitated cleavage plane .
the tumors were removed in piecemeal pattern until they were completely resected under the surgical microscope . following resection and hemostasis ,
mpes are world health organization grade i ( low - grade ) ependymomas originating mostly from the filum terminale or the terminal ventricle51419 ) . for this reason mpes
are detected as solitary tumors more commonly at conus - cauda - filum levels51921 ) .
intracranial , cervical and thoracic region lesions are considered as csf dissemination of mpes , yet reverse situations have also been reported2125 ) .
tumor dissemination is basically caused by violation of tumor capsule of mpes caused by piecemeal tumor removal , traumatic spinal tap , spinal trauma , spinal instrumentation , and tumor hemorrhage411151820212327 ) .
mpe is iso - intense on t1- and hyper - intense on t2-weighted mri with heterogenous imaging properties on t2-weighted scans .
mpe is composed of cellular areas harboring rosettes and pseudorosettes intermingled with papillary regions , which have vascular cores in mucoid matrix141921 ) .
this kind of presentation could not be directly considered as dissemination , since both tumors are in the site of classical origin of mpes21 ) .
ten cases have been presented up to date ( table 1)28910161721 ) . including the present case , analyses of the 11 patients have revealed some facts .
there is a male predominance ( male : female=6:1 ; sex was not mentioned for 4 patients10 ) ) , which is opposite to the ependymomas which are commonly observed in females6 ) .
median age at presentation is 15 years ( range , 7 - 39 years ; age was not mentioned for 4 patients10 ) ) .
this depicts that concomitant double presentation of mpe is mostly observed in children and young adults .
surgical approach was aimed in all tumors , which was successful in all tumors , except one .
, both tumors had been resected en bloc , yet mib-1 index was high ( 9.1% ) .
in the second patient , the second tumor could be excised partially , and local radiotherapy was given to the residual tumor bed16 ) .
khalatbari et al.10 ) operated 4 patients ( 6 tumors were removed en bloc , 3 tumors were removed gross totally in piecemeal fashion ) and gave adjuvant radiotherapy to 3 patients .
mpes have 3.6 times shorter time to metastasis compared to other type of low - grade ependymomas .
so , it is not clear yet if concomitant double tumor presentation is due to two different primary tumors or dissemination one from the other one17 ) .
the second lesions have mainly been observed at the lumbosacral junction , which might be due to drop metastasis from the rostral lesion289161721 ) .
however , tumor dissemination is observed in 33% of patients with mpe at 5-year follow - up20 ) .
so , long - term follow - up should be conveyed in every patient with a diagnosis of mpe , even in cases with aggressive therapy1323 ) .
good prognosis is expected in 70% of the patients with appropriate treatment without considering total resection as a must22223 ) .
concomitant double presentation of myxopapillary ependymoma is a rare entity with a good prognosis ; however long term follow - up is necessary to observe tumor progression in a timely fashion .
a 32-year - old man presented with gradually increasing bilateral buttock pain . 
 he had intermittent claudication . 
 multiple , homogenously enhanced intradural extramedullary lesions at l2-l3 and l5-s1 levels were observed on magnetic resonance imaging . 
 the tumors were debulked and were removed in piecemeal pattern until they had completely been resected . 
 histopathological examination of the surgical specimens confirmed that both tumors were myxopapillary ependymomas ( mpe ) . 
 mpe presenting as concomitant double tumor at conus - cauda - filum level are very rare . 
 this kind of presentation could not be directly considered as dissemination , since both tumors were in the site of classical origin of mpe . 
 ten cases of double spinal mpes have been reported to date . including the present case , analysis of the 11 patients revealed some facts . 
 there is a male predominance , which is opposite to the ependymomas that are commonly observed in females . 
 median age at presentation is 15 years . 
 most pronounced symptom is low back pain that sometimes radiates to lower extremities . 
 surgical approach was aimed in all tumors , which could be succeeded in all tumors except one . 
 adjuvant radiation therapy was applied in 5 patients . 
 no recurrences have been reported after surgery or surgery + radiotherapy regimens .