|Year : 2013 | Volume
| Issue : 2 | Page : 132-134
Thoracic intramedullary spinal epidermoid tumor: A rare entity
Manoj Kumar1, Monika S Malgonde2, S Ashok Kumar3
1 Department of Orthopaedics, MGIMS, Sevagram, Wardha, Maharashtra, India
2 Department of Otorhinolaryngology, MGIMS, Sevagram, Wardha, Maharashtra, India
3 Department of Neuro Surgery, MGIMS, Sevagram, Wardha, Maharashtra, India
|Date of Web Publication||10-Sep-2013|
Department of Orthopedics and Traumatology, M.G.I.M.S., Sewagram - 442 102, Wardha, Maharashtra
Source of Support: None, Conflict of Interest: None
Epidermoid cyst in the spinal cord is a rare condition. It constitutes of only 0.6-1.1% of all spinal tumors. We are reporting a case of a 22-year-old female who presented with complaints of tingling and numbness in both lower limbs since past 3 years and weakness in both lower limbs since past 1 year, which gradually progressed. Since last 3 months she was unable to walk and get up from their squatting position. Magnetic resonance imaging of spine revealed a mid-thoracic intramedullary mass with obliteration of anterior and posterior subarachnoid space, which was confirmed as an intramedullary epidermoid cyst at surgery. Total excision of intramedullary epidermoid tumor was performed. Histopathological examination of resected specimen confirmed the diagnosis of epidermoid cyst. The patient recovered progressively after initial deterioration in neurological status.
Keywords: Cyst, epidermoid, intramedullary, magnetic resonance imaging
|How to cite this article:|
Kumar M, Malgonde MS, Kumar S A. Thoracic intramedullary spinal epidermoid tumor: A rare entity. Saudi J Health Sci 2013;2:132-4
| Introduction|| |
Epidermoid cyst is a slow growing rare lesion, resulting apparently from the inclusion of ectodermal tissue during the closure of the neural tube. It represents <1% of all intraspinal tumors in adults. , Most of the spinal epidermoid cysts subdural and extra medullary, while intramedullary localization is very rare. Less than 60 cases have been reported until date since the first reporting of the entity by Chiari in 1833, and out of these, very few cases are evaluated by magnetic resonance imaging (MRI). ,, Most common location of intraspinal epidermoid cyst is thoracic and lumbo-sacral regions. Two most common locations are T 4 -T 6 and T 11 -T12. , We are reporting here the case of a 22-year-old female patient with thoracic intramedullary epidermoid cyst evaluated by MRI.
| Case Report|| |
A 22-year-old female presented with a history of backache, tingling, and numbness in both lower limbs since past 3 years and weakness in both lower limbs since past 1 year, which gradually progressed over time. Since last 3 months she was unable to walk and get up from squatting position, also she had difficulty of gripping the footwear since 3 months. There was no history suggestive of bowel and bladder disturbances. There was no history of trauma or any spinal procedure in the past. There was no cutaneous spine manifestation. From history, it appears that etiology was congenital with very late presentation.
Clinical examination revealed spastic paraparesis with tone increased in both the lower limbs, power was 3/5 in the right lower limb and 3-4/5 in the left lower limb according to MRC scale. Deep tendon reflexes were brisk and planter was extensor. Sensory examination revealed a suspended sensory loss to pain from T6 to T9 segments and loss of all modalities of sensation below T10 segment. Upper limbs were normal. Her general and systemic examination was normal.
MRI of spine was done to reveal a well-defined, oval intramedullary mass lesion of an approximate size of 2.22 × 0.95 × 0.85 cm in the thoracic cord extending from the upper end plate of T7 vertebra to the upper end plate of T8 vertebra, causing fusiform enlargement of cord with obliteration of anterior and posterior subarachnoid spaces at the same level. The lesion was iso to hypo intense on T1-weighted image [Figure 1], predominantly hyper intense on T2-weighted image [Figure 2], and showed homogenous post contrast enhancement more marked peripherally and a diagnosis of ependymoma or astrocytoma was given by an radiologist [Figure 3].
|Figure 1: T1 weighted contrast sagital magnetic resonance imaging of dorsal spine showing intramedullary mass lesion at T7-8 level|
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|Figure 2: T2 weighted hyperintese sagital magnetic resonance imaging of dorsal spine showing intramedullary mass lesion at T7-8 level|
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|Figure 3: T1 and T2 weighted axial magnetic resonance images of T7-T8 vertebra showing intramedullary mass lesion|
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After complete evaluation, T6-T9 laminectomy was performed. Dura was found bulging. Dura was opened longitudinally and cord found widened. Posterior midline myelotomy at the T7-T8 level with total excision of tumor using micro neurosurgical technique was performed along with duroplasty. Intraoperatively, there was pearly white, flaky lesion within the cord substance that was pathognomic of epidermoid cyst. On frozen section, the same was confirmed.
Histopathological examination of resected specimen revealed fibrous tissue lined in combination with compressed stratified squamous epithelium. These findings were consistent with epidermoid cyst.
Postoperatively, physiotherapy and rehabilitation was provided. The patient made an uneventful recovery with subsequent improvement in her neurological status. After 2 months, the patient was followed-up and her neurological examination showed 4+/5 power in both lower limbs with some residual spasticity. The patient was able to walk without support.
| Discussion|| |
Epidermoid cyst rarely occurs in CNS and even rarer in spinal canal. The incidence of epidermoid cysts among intracranial tumors is estimated to be 0.2-1%, which is much less among the spinal tumours. Guidetti and Gagliardi reported a series of 3844 intracranial and 452 intraspinal tumors in patients of all ages and found incidence of 0.8% for cranial epidermoid cysts and 0.7% for spinal epidermoid cysts. , But in a recent study reported by Bansal et al., the incidence of epidermoid tumors are 20.7% in a series of 82 patients of age group 1-18 years. 
Pathogenesis of spinal epidermoid cyst is mainly congenital, which occurs due to displacement of ectodermal inclusions during closure of neural tube during third to fifth week of gestation. The congenital epidermoid cysts are frequently associated with other congenital abnormalities like Hemi vertebra, dermal sinus, Spina bifida, and Syringomyelia. Manno et al., reported a series of 90 intraspinal epidermoid cysts collected from the literature, of which 39 were acquired and 51 congenital. Acquired spinal epidermoid cyst was mainly due to single or multiple lumbar spinal puncture or after meningomyelocele repair, and they are thought to result from iatrogenic penetration of skin fragments, but it takes years to happen. ,,,
A reason for the delay in diagnosis of epidermoid cyst was its slow growth, and clinical presentation of this tumor is not specific. Clinical presentation is usually neurological such as progressive paraparesis, sensory loss but rarely urological involvement may occur.  Intramedullary epidermoid cyst is diagnosed on the basis of operative and histological findings.
MRI is a good tool for early diagnosis. Epidermoid cyst on MRI shows variable signal intensity between the different cases and even between different parts of same cyst. Other features include fairly well-defined limits, absence of oedema in surrounding tissue, presence of calcification, and peripheral enhancement on injection of contrast (gadolinium). Disparity of signal intensity is mainly due to variable lipid and protein composition in these lesions, also margins of these lesion are shaggy, which could be because of chronic inflammatory response to the squamous tissue "leak" through the capsule and variable gliosis along the margin, extending into the cord. These feature helps in differentiating these lesions from other intramedullary tumors such as dermoid cyst, ependymoma, astrocytoma, teratoma, and haemangioma. ,
In our case, MRI of dorsal spine showed a well-defined homogenously enhancing oval intramedullary mass lesion in the thoracic cord, iso to hypo intense on T1-weighted and hyper intense on T2-weighted images also showing homogenous post contrast enhancement more marked peripherally. These finding are consistent with the diagnosis of epidermoid cyst.
Histologically, epidermoid and dermoid cysts are lined by stratified squamous epithelium supported by an outer layer of collagenous tissue; progressive desquamation of keratin from epithelial lining toward the interior of the cyst produces a soft white material. Dermoid cyst is differentiated from epidermoid cyst with the presence of skin adnexa. ,
The treatment of choice for an intramedullary epidermoid cyst is total surgical excision that includes emptying of the cyst material and removal of the capsule. In some cases, capsule is thin and tightly adherent to the cord or surrounding neural tissue and its complete removal can cause neurological deficits. In such type of cases, capsule should be left in place. ,,,, In our case, total excision of tumor using micro neurosurgical technique was performed. The risk of recurrence occurs. Even partial removal of intramedullary epidermoid cyst resulted in complete remission of symptoms. If recurrence occurs, another surgery may relieve the symptoms. Radiotherapy was mentioned as the treatment modality for epidermoid cyst for only one case in the literature. ,
| Conclusion|| |
Spinal intramedullary epidermoid cysts are rare tumors without specific clinical presentation. Early diagnosis can be done by MRI, which shows hypo intense signal on T1-weighted image and hyper intense signal on T2-weighted image along with peripheral enhancement on injection of gadolinium. Clinical presentation is usually neurological. Surgical excision is the treatment of choice, which not only resulted in cessation of clinical progression but also in the remission of symptoms.
| References|| |
|1.||Lunardi P, Missori P, Gagliardi FM, Fortuna A. Long-term results of the surgical treatment of spinal dermoid and epidermoid tumors. Neurosurgery 1989;25:860-4. |
|2.||Penisson-Besnier I, Guy G, Gandon Y. Intramedullary epidermoid cyst evaluated by computed tomographic scan and magnetic resonance imaging: Case report. Neurosurgery 1989;25:955-9. |
|3.||Roux A, Mercier C, Larbrisseau A, Dube LJ, Dupuis C, Del Carpio R. Intramedullary epidermoid cysts of the spinal cord. Case report. J Neurosurg 1992;76:528-33. |
|4.||Kumar A, Singh P, Jain P, Badole CM. Intramedullary spinal epidermoid cyst of the cervicodorsal region: A rare entity. J Pediatr Neurosci 2010;5:49-51. |
|5.||Cincu R, Lazaro JF, Liesa JL, Callizo JR. Dorsal intramedullary spinal epidermoid cysts: Report of two cases and review of literature. Indian J Orthop 2007;41:395-7. |
|6.||Ferrara P, Costa S, Rigante D, Mule A, D'Aleo C, Pulitanò S, et al. Intramedullary epidermoid cyst presenting with abnormal urological manifestations. Spinal cord 2003;41:645-8. |
|7.||Guidetti B, Gagliardi FM. Epidermoid and dermoid cysts. Clinical evaluation and late surgical results. J Neurosurg 1977;47:12-8. |
|8.||Chandra PS, Manjari T, Devi BI, Chandramouli BA, Srikanth SG, Shankar SK. Intramedullary spinal epidermoid cyst. Neurol India 2000;48:75-7. |
|9.||Bansal S, Suri A, Borkar SA, Kale SS, Singh M, Mahapatra AK. Management of intramedullary tumors in children: Analysis of 82 operated cases. Childs Nerv Syst 2012;28:2063-9. |
|10.||Manno NJ, Uihlein A, Kernohan JW. Intraspinal epidermoids. J Neurosurg 1962;19:754-65. |
|11.||Halcrow SJ, Crawford PJ, Craft AW. Epidermoid spinal cord tumour after lumbar puncture. Arch Dis Child 1985;60:978-9. |
|12.||Shaywitz BA. Epidermoid spinal cord tumors and previous lumbar punctures. J Pediatr 1972;804:638-40. |
|13.||Kirsch WM, Hodges FJ 3 rd . An intramedullary epidermal inclusion cyst of the thoracic cord associated with a previously repaired meningocele. Case report. J Neurosurg 1966;24:1018-20. |
|14.||Bretz A, Van den Berge D, Storme G. Intraspinal epidermoid cyst successfully treated with radiotherapy: Case report. Neurosurgery 2003;53:1429-31. |
[Figure 1], [Figure 2], [Figure 3]