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Case Report

Thoracic meningioma with ossification: Case report

Department of Neurosurgery, Allen Hospital, Unitypoint Clinic, Waterloo, Iowa, United States.
Department of Pathology, Allen Hospital, Unitypoint Clinic, Waterloo, Iowa, United States.
Corresponding author: Nikolay L. Martirosyan, Department of Neurosurgery, Allen Hospital, Unitypoint Clinic, Waterloo, Iowa, United States.

This is an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-Share Alike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms.

How to cite this article: Buchanan D, Martirosyan NL, Yang W, Buchanan RI. Thoracic meningioma with ossification: Case report. Surg Neurol Int 2021;12:505.



The incidence of spinal meningiomas is 0.33/100000 population, and ossified spinal meningiomas are even less commonly encountered.

Case Description:

A 64-year-old male presented with a progressive T4-level thoracic myelopathy. MR imaging revealed an intradural extramedullary mass that significantly compressed the spinal cord. The accompanying CT demonstrated hyperdensities within the lesion consistent with punctate calcification vs. ossification (i.e. consistent with histological bone formations within tumor). The patient underwent complete resection of the tumor resulting in a full recovery of neurological function within 6 postoperative weeks. The pathological specimen showed findings consistent with an ossified spinal meningioma.


Here, we identified a rare case of an ossified thoracic T4 meningioma occurring in a 64-year-old male.


Spinal meningioma


A quarter of spinal tumors are meningiomas, and over 90% of them are benign.[1] They occur more in females (4:1 female/male ratio), and 82% are predominantly located in the thoracic spine.[20] Notably, 5% of these lesions are calcified, while <1% are ossified (i.e. exhibiting histological bone formation within the tumor).[13,17] Here, we reviewed 35 cases of ossified spinal meningiomas reported in literature and added an additional case of a T4 lesion found in a 64-year-old male who presented with a T4 lesion[1,27] [Table 1].

Table 1:: Summary of cases with ossified thoracic meningioma.


A 64-year-old male presented with a progressive T4-level paraparesis characterized by progressive numbness below the waistline, weakness in both lower extremities, and ataxia of gait. His neurological examination showed diffuse 4/5 bilateral lower extremity weakness with a relative T4-sensory level to pin appreciation.


The thoracic MRI revealed a large right-sided dorsal intradural extramedullary lesion contributing to severe compression of the spinal cord at T4-level. The CT scan confirmed the lesion was hyperdense, consisting of intratumoral ossification [Figure 1]. The predominant differential diagnoses included ossified meningioma versus schwannoma.

Figure 1:: Pre-operative imaging. (a) sagittal MRI contrast-enhancing intradural extramedullary lesion at T4 with severe compression of the spinal cord, (b) sagittal CT demonstrates hyperdense signal within the tumor suggesting calcifications.


Under neuromonitoring and following a T4-T5 laminectomy, a midline durotomy was performed. This revealed an intradural extramedullary tumor with a base adherent to the right lateral dura. The tumor was dissected off the dura allowing for gross total resection (GTR); the sensory rootlets enmeshed in the tumor capsule were easily dissected off the lesion and preserved. A watertight closure followed, and there were no intraoperative neuromonitoring changes. Within 6 postoperative months, the patient was neurologically intact except for some mild residual gait ataxia, (i.e. requiring a cane to ambulate).

Surgical pathology

Gross pathology showed the lesion was irregular, tan, and rubbery, measuring 9 × 10 × 13 mm. On microscopy, there were meningothelial cells with oval to spindle-shaped nuclei containing occasional intranuclear pseudoinclusions. Frequent swirls of psammoma bodies were also seen. Additional areas showed more extensive “ossification” (i.e. bone formation, osseous metaplasia). As the tumor showed little mitotic activity, and there were no areas of hypercellularity, the final diagnosis was for a WHO grade I (benign) meningioma [Figure 2].

Figure 2:: Hematoxylin and eosin (×20) images demonstrate (a) meningothelial cells with swirls, (b) numerous psammoma bodies, (c and d) ossifications.


One percent of spinal meningiomas are ossified. The majority occur in females[1,20] [Table 1]. Ossification of spinal meningiomas is attributed to metaplasia of the arachnoid.[21] Estrogen deficiency is also suspected to intensify the calcification/ossification of meningiomas where there are necrotic fibroblasts and an elevated number of collagen fibrils.[21]

Incidence and prognosis for ossified spinal meningiomas

Of the 35 ossified meningiomas identified in the literature, only four occurred in males[21] [Table 1]. GTRs best correlate with marked neurological improvements.[27] The resection of the involved adjacent dura warrants duroplasty, which increases the complexity of the procedure.[1,21,27] Perhaps, a complete ossification, firmness of the tumor, and size can increase surgical morbidity because of difficulty to manipulate the tumor without compressing the spinal cord. In some cases, GTR is unsafe because of an absent distinct plane between the tumor and the spinal cord.

Although most cases reported favorable outcomes, others reported major perioperative morbidities, including paraplegia, complete sensory loss, cerebrospinal fluid leakage, and stroke. Despite these complications, following appropriate treatment/ medication, many patients sustained adequate recoveries.[21] However, most patients did not fully recover function and exhibited various degrees of neurological symptoms.

Symptom onset of ossified spinal meningiomas

Most of the 35 cases of ossified meningiomas presented with progressive myelopathy that worsened over a prolonged period. The clinical presentation was nonspecific and slow-progressing, therefore raise patients’ concern only when severely symptomatic. MRI identifies the size/extent of the mass, and CT studies are utilized to identify small calcifications/ossification. However, imaging modalities are unable to differentiate between ossification and calcification. The final diagnosis is made based on histopathologic evaluation.

Prediction of local recurrence

Only 17 cases had reported long-term follow up, and none of the patients had a recurrence. Interestingly, there was no recurrence in patients with subtotal resection [Table 1].


Only 1% of spinal meningiomas are ossified, and few occur in males. Here we present a 64-year-old male with a T4 ossified meningomas responsible for a thoracic paraparesis that resolved following gross total tumor resection.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


  1. , , , , . Ossified spinal meningiomas: Clinical and surgical features. Clin Neurol Neurosurg. 2016;142:93-7.
    [Google Scholar]
  2. , , , . Ossified thoracic spinal meningioma with lamellar bone formation presented with paraparesis. J Orthop Trauma Rehabil. 2014;18:106-9.
    [Google Scholar]
  3. , , , . Ossification in an extra-intradural spinal meningioma-pathologic and surgical vistas. Spine J. 2013;13:e21-6.
    [Google Scholar]
  4. , , , , . Spinal osteoblastic meningioma with hematopoiesis: Radiologic-pathologic correlation and review of the literature. Ann Diagn Pathol. 2016;24:30-4.
    [Google Scholar]
  5. , , , , , . Ossified-calcified intradural and extradural thoracic spinal meningioma with neural foraminal extension. Spine J. 2016;16:e35-7.
    [Google Scholar]
  6. . Removal of an ossified ventral thoracic meningioma. Case report. J Neurosurg. 1972;37:728-30.
    [Google Scholar]
  7. , , , , . Surgical resection without dural reconstruction of a lumbar meningioma in an elderly woman. Eur Spine J. 2009;18:232-5.
    [Google Scholar]
  8. , , , . Intraspinal osteogenic meningioma: Report of a case. J Formos Med Assoc. 1999;98:218-21.
    [Google Scholar]
  9. , , , . Totally ossified metaplastic spinal meningioma. J Korean Neurosurg Soc. 2013;54:257-60.
    [Google Scholar]
  10. , , , , , . Clinicopathologic analysis of ossification in spinal meningioma. Noshuyo Byori. 1994;11:115-9.
    [Google Scholar]
  11. , , , , , . Ossified spinal tumour in a 58-year-old woman with increasing paraparesis. Neuropathology. 2010;30:194-6.
    [Google Scholar]
  12. , , , . Thoracic ossified meningioma and osteoporotic burst fracture: Treatment with combined vertebroplasty and laminectomy without instrumentation-case report. J Neurosurg Spine. 2006;4:256-9.
    [Google Scholar]
  13. , , , , . Ossified metaplastic spinal meningioma without psammomatous calcification: A case report. Yonago Acta Med. 2019;62:232-5.
    [Google Scholar]
  14. , , , . Ossified thoracic spinal meningioma in childhood: A case report and review of the literature. Clin Neurol Neurosurg. 2001;103:247-9.
    [Google Scholar]
  15. , , , , , , . Two cases of ossified spinal meningioma. Neurol Surg. 1996;24:351-5.
    [Google Scholar]
  16. , , , . Ossified spinal meningioma en plaque. Spine (Phila Pa 1976). 1993;18:2340-3.
    [Google Scholar]
  17. , , , , . Heterotopic mineralization (ossification or calcification) in tendinopathy or following surgical tendon trauma. Int J Exp Pathol. 2012;93:319-31.
    [Google Scholar]
  18. , , , , , . Thoracic psammomatous spinal meningioma with osseous metaplasia: A very rare case report. Asian J Neurosurg. 2015;12:270-2.
    [Google Scholar]
  19. . A spinal meningioma containing bone. Br J Surg. 1928;15:675-7.
    [Google Scholar]
  20. , , , , , , . Spinal meningiomas: Review of 174 operated cases. Neurosurgery. 1989;25:153-60.
    [Google Scholar]
  21. , , . Ossified spinal meningioma: A case report and a review of the literature. Surg J (NY). 2019;5:e137-41.
    [Google Scholar]
  22. , , , , . Spinal meningioma containing bone: A case report and review of literature. BMJ Case Rep. 2009;2009:bcr11.2008.1186.
    [Google Scholar]
  23. , , , , , , . Ossified thoracic spinal meningioma with hematopoiesis: A case report and review of the literature. Case Rep Clin Med. 2013;2:24-8.
    [Google Scholar]
  24. , , , , , , . Immunohistochemical findings of multiple ossified en plaque meningiomas in the thoracic spine. J Clin Neurosci. 2009;16:1660-2.
    [Google Scholar]
  25. , , , , , . Thoracic psammomatous meningioma with osseous metaplasia: A controversial diagnosis of a case report and literature review. World J Surg Oncol. 2019;17:150.
    [Google Scholar]
  26. , . Entirely ossified subdural meningioma in thoracic vertebral canal. Spine J. 2016;16:e11.
    [Google Scholar]
  27. , , , , , , . Completely ossified thoracic intradural meningioma in an elderly patient: A case report and literature review. Medicine (Baltimore). 2020;99:e20814.
    [Google Scholar]
  28. , , , , . Spinal metaplastic meningioma with osseous differentiation in the ventral thoracic spinal canal. Acta Med Okayama. 2014;68:313-6.
    [Google Scholar]
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