EDP Sciences logo
Submit your paper
Search
Menu
All issues Volume 5 (2019) SICOT-J, 5 (2019) 34 Full HTML
Open Access
Review
Issue
SICOT-J
Volume 5, 2019
Article Number 34
Number of page(s) 5
Section Spine
DOI https://doi.org/10.1051/sicotj/2019024
Published online 27 September 2019

© The Authors, published by EDP Sciences, 2019

Licence Creative CommonsThis is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Introduction

Fibrous dysplasia (FD) is a non-neoplastic tumor-like congenital process characterized by a localized defect in osteoblastic differentiation and maturation, with replacement of normal bone with large fibrous stroma and islands of immature woven bone. It is subclassified as monostotic and polyostotic lesions [1]. The spine is affected in only 2.5% of cases [2] and monostotic FD of the spine is uncommon. This case report covers the diagnosis and treatment of a patient with monostotic FD of C2 with a mixed osteosclerotic and osteolytic radiologic appearance, which was revealed by a pathological fracture of the odontoid process.

Case report

The patient was a 30-year-old woman who presented with a considerable spontaneous pain in the upper neck. She had no other significant medical history. Physical examination revealed a cervical stiffness without neurologic signs or symptoms. Radiographs of the cervical spine revealed a pathological fracture involving the odontoid process of C2. CT confirmed the fracture of the odontoid process and the replacement of normal bone by ground-glass mineralization and a centimetric lytic area with poorly defined margins involving the inferior part of the vertebral body and inferior endplate (Figure 1).

thumbnail Figure 1

(a) Sagittal, (b) coronal and (c) axial CT-scan reformations of the upper cervical spine in a 30-year-old woman, showing the mixed appearance of the C2 vertebral body with a ground-glass appearance and osteolytic areas in the base of the odontoid process with a pathologic fracture (thin arrow) and in the inferior part of the vertebral body with partial destruction of the inferior endplate (thick arrow).

MRI of the cervical spine revealed low signal intensity of the whole C2 vertebra on both T1- and T2-weighted images, with mild homogenous enhancement after gadolinium administration that suggested a fibrous and/or mineralized content (Figure 2). There was no soft tissue extension and the C2–3 intervertebral disc was normal. Standard blood laboratory investigations, including C-reactive protein level, gave normal serum values. A full metastatic imaging workup including whole-body CT revealed no other abnormal findings.

thumbnail Figure 2

T2-weighted, T1-weighted, T1-weighted with intra-venous contrast administration midline sagittal MR images of the cervical spine showing the low signal intensity of the C2 vertebral body and odontoid process (a, b), with enhancement after contrast administration (c), and a solution at the junction between the odontoid process and vertebral body (a–c).

Owing to the odontoid process fracture and the vertebral instability, a surgical procedure combining C0–C5 fixation and posterior bone grafting was decided. The surgery was performed in the prone position and under general anesthesia. The neural arch of C2 was resected up to the lateral masses, and the bone resected was sent for pathological and bacteriological examinations. Screws (4.5-mm diameter, 12-mm size) were inserted in lateral masses of C3, C4, and C5 bilaterally according to the technique of Roy–Camille. Two vertical rods connected to an occipital plate were then fixed to C3, C4, and C5 screws and the plate was fixed to the occiput, thanks to three screws bilaterally. An autologous bone graft was withdrawn from the posterior iliac crest and placed from occiput to C3. Pathological examination of the resected bone was inconclusive as well as microbiology for Gram staining and bacteriological cultures including acid-fast bacilli and fungal assays. Therefore, a percutaneous needle biopsy of the osteolytic inferior part of the C2 vertebral body was performed under local anesthesia and fluoroscopic guidance. A 11-gauge 10-cm-long coaxial biopsy needle (KBC1110, Merit Medical®, Galway, Ireland) was advanced up to C2 vertebral body through an anterolateral ascending approach between the jugulo-carotid bundle and the trachea-oesophagus, and bone samples from C2 vertebral body were obtained (Figure 3). The final pathological diagnosis was FD, confirmed by a pathological review in a second institution. No secondary aneurysmal bone cyst and no sign of malignant transformation were seen. The patient received intravenous pamidronate (60 mg/day over 3 days every 6 months). At 3-month follow-up, the patient was doing well, except for mild cervical posterior neck pain and a follow-up radiograph showed that the fixation material was in good position. Some widening of the C5–6 facet joints, which could correspond to joint laxity below the fixed cervical levels, was noted. At 26-month follow-up, the patient still experienced mild persistent cervical posterior neck pain and stiffness, possibly related to the C5–6 laxity. Since the patient was pregnant at this last consultation, static and dynamic radiographic examinations as well as discussion of an indication of a C5–6 anterior joint fusion were postponed.

thumbnail Figure 3

Percutaneous needle biopsy of C2 under fluoroscopic guidance with an anterolateral approach.

Discussion

FD is a genetic, non-inherited condition with no sex predilection that results in a somatic mosaicism of affected osteoblastic cells producing a poorly organized fibrous connective tissue interwoven with trabeculae of immature bone [3]. It appears to be caused by mutations in the GNAS1 gene that encodes for the alpha subunit of the stimulatory G-protein Gs [4].

We report a case of monostotic FD of C2 in a 30-year-old woman with a locally aggressive radiologic appearance, which was revealed by a pathological fracture of the odontoid process.

The spine accounts for only 1.4% of cases of monostotic FD [5]. Including ours, 18 cases of monostotic FD involving the cervical spine have been previously reported to our knowledge [6–20]. These 18 cases concerned 13 males and five females, most commonly in the third to fifth decades of life (mean age 32.5 years [range 11–56]), and involved C2 in seven cases (39%), C4 in five cases, C1 in three cases, and C3, C6, and C7 in one case each. Patients most commonly presented with axial neck or back pain, but in some cases, FD was an incidental finding. Only one patient had neurological symptoms, i.e. a 35-year-old man who presented a cervico-brachial neuralgia with sensitive symptoms.

Cervical FD may be revealed by a pathological fracture. Back to 1989, 11 cases including ours (mean age 37 years [range 17–63) of monostotic (n = 4) or polyostotic (n = 7) FD of the cervical spine revealed by a pathological fracture have been reported (Table 1). Interestingly, 5 out of the 11 cases involved C2. Only one of these was monostotic.

Table 1

Reported cases of cervical spine fibrous dysplasia presenting with a pathological fracture.

CT features of vertebral FD do not differ from those of extraspinal location and included well-defined predominantly osteolytic lesions with ground-glass mineralization, sclerotic rim formation, an expansile nature with bone remodeling, and rarely cortical disruption. Vertebral body weight loss is frequent [21]. On T1-weighted images, low signal intensity is present in 67% of the lesions and heterogeneous signal intensity in 33%. On T2-weighted images, lesions show heterogeneous signal intensity with a low signal intensity rim in half of the cases; after intravenous gadolinium administration, lesion enhancement is homogeneous in 50% of cases and heterogeneous in 50% [21]. This diversity of the MR findings in FD is explained by their variable contents in bony trabeculae, cellularity, collagen fibers, cystic changes, and hemorrhage [22].

FD is traditionally considered to stop growing in the mature skeleton, but this may not actually be the case, especially with polyostotic presentation [22, 23]. In a single case of FD involving C2 in a 21-year-old man who underwent posterior spinal fusion from C1 to C3 performed with use of two cortico-cancellous grafts from the posterior iliac crest, the routine radiography follow-up 20 years later demonstrated extension of the expansile lesion through the bone graft to C3, with the classical ground-glass appearance. MRI confirmed the extension of the FD lesion into the posterior elements of C3 through the fusion bone graft [9, 24].

Our case exhibited some aggressive radiological features, namely a pathological fracture of the odontoid process and an osteolytic area involving the inferior part of the C2 vertebral body, which led us to perform a guided biopsy for pathological evaluation. A locally aggressive variant of FD characterized by cortical destruction that mimics malignancy on CT and MRI has been described [25, 26]. A large number of reported cases of locally aggressive FD involved the craniofacial skeleton, especially the maxilla and mandible in young patients [25, 27, 28]. Among the 14 cases of locally aggressive FD outside the skull previously reported, none was involving the spine [25, 26, 28–31].

Possible other causes of aggressive radiological patterns with cortical destruction and a soft tissue mass encountered in FD include malignant transformation and secondary aneurysmal bone cyst formation. Vertebral FD with secondary aneurysmal bone cyst formation is uncommon and usually manifests as an expanding lesion [32, 33]. Malignant transformation of vertebral FD is very uncommon and more frequent in polyostotic than monostotic FD [25]. Both secondary aneurysmal bone cyst formation and malignant transformation were absent in our case.

In conclusion, cervical FD may present in a young adult as a monostotic lesion, particularly in C2, with a pathological fracture and some aggressive radiologic features. In such cases, a ground-glass mineralization may suggest the diagnosis but a biopsy is required.

Conflict of interest

The authors declare that they have no conflict of interest.

References

  1. Lichtenstein L (1938) Polyostotic fibrous dysplasia. Arch Surg 36(5), 874–898. [Google Scholar]
  2. Harris WH, Dudley HR, Barry RJ (1962) The natural history of fibrous dysplasia: an orthopaedic, pathological, and roentgenographic study. J Bone Jt Surg 44(2), 207–233. [CrossRef] [Google Scholar]
  3. Dahlin DC, Unni KK. 1986. Bone tumors: general aspects and data on 8,547 cases, 4th edn. Thomas, USA. Available from https://www.osti.gov/scitech/biblio/5518830. [Google Scholar]
  4. Schwindinger WF, Francomano CA, Levine MA (1992) Identification of a mutation in the gene encoding the alpha subunit of the stimulatory G protein of adenylyl cyclase in McCune-Albright syndrome. Proc Natl Acad Sci 89(11), 5152–5156. [CrossRef] [Google Scholar]
  5. Gibson MJ, Middlemiss JH (1971) Fibrous dysplasia of bone. Br J Radiol 44(517), 1–13. [CrossRef] [PubMed] [Google Scholar]
  6. Arantes M, Vaz AR, Honavar M, Resende M, Pereira JR (2008) Fibrous dysplasia of the first cervical vertebra. Spine 33(24), E933–E935. [CrossRef] [PubMed] [Google Scholar]
  7. Ehara S, Kattapuram SV, Rosenberg AE (1992) Fibrous dysplasia of the spine. Spine 17(8), 977–978. [CrossRef] [PubMed] [Google Scholar]
  8. Schoenfeld AJ, Koplin SA, Garcia R, et al. (2010) Monostotic fibrous dysplasia of the spine: a report of seven cases. J Bone Jt Surg Am 92(4), 984–988. [CrossRef] [Google Scholar]
  9. Hu SS, Healey JH, Huvos AG (1990) Fibrous dysplasia of the second cervical vertebra. A case report. JBJS 72(5), 781–783. [CrossRef] [Google Scholar]
  10. Ohki I (1990) Monostotic fibrous dysplasia in the spine. J West Pacif Orthop Assoc 27, 107–110. [Google Scholar]
  11. Iwasaki M, Hida K, Yano S, Iwasaki Y (2008) Case of cervical monostotic fibrous dysplasia with a large cyst. No Shinkei Geka Neurol Surg 36(5), 429–433. [Google Scholar]
  12. Stirrat AN, Fyfe S, Fisher CJ (1989) Fibrous dysplasia of the axis: a case report. Spine 14(2), 243–245. [CrossRef] [PubMed] [Google Scholar]
  13. Marshman LAG, David KM, O’Donovan DG, Chawda SJ (2004) Fibrous dysplasia of the cervical spine presenting as a pathological fracture. Br J Neurosurg 18(5), 527–533. [CrossRef] [PubMed] [Google Scholar]
  14. Schlumberger MHG (1946) Fibrous dysplasia of single bones (monostotic fibrous dysplasia). Mil Surg 99, 504–527. [PubMed] [Google Scholar]
  15. Rosendahl-Jensen S (1956) Fibrous dysplasia of the vertebral column. Acta Chir Scand 111(6), 490–494. [PubMed] [Google Scholar]
  16. Proschek D, Orler R, Stauffer E, Heini P (2007) Monostotic fibrous dysplasia of the spine: report of a case involving a cervical vertebra. Arch Orthop Trauma Surg 127(2), 75–79. [Google Scholar]
  17. Villas C, Martínez-Peric R (1992) Monostotic fibrous dysplasia of a cervical vertebra. Eur Spine J 1(2), 137–139. [CrossRef] [PubMed] [Google Scholar]
  18. Sambasivan M, Sanalkumar P, Mahesh S, Nair K, Basheer A (2008) Monostotic fibrous dysplasia of the C4 cervical spine. Neurol India 56(4), 497–498. [PubMed] [Google Scholar]
  19. Resnik CS, Lininger JR (1984) Monostotic fibrous dysplasia of the cervical spine: case report. Radiology 151(1), 49–50. [CrossRef] [PubMed] [Google Scholar]
  20. Wu FL, Jiang L, Liu C, et al. (2013) Fibrous dysplasia of the mobile spine: report of 8 cases and review of the literature. Spine 38(23), 2016. [CrossRef] [PubMed] [Google Scholar]
  21. Park SK, Lee IS, Choi JY, et al. (2012) CT and MRI of fibrous dysplasia of the spine. Br J Radiol 85(1015), 996–1001. [CrossRef] [PubMed] [Google Scholar]
  22. Chow LC, Griffith J, Chow WH, Kumta SM (2000) Monostotic fibrous dysplasia of the spine: report of a case involving the lumbar transverse process and review of the literature. Arch Orthop Trauma Surg 120(7–8), 460–464. [Google Scholar]
  23. Proschek D, Orler R, Stauffer E, Heini P (2007) Monostotic fibrous dysplasia of the spine: report of a case involving a cervical vertebra. Arch Orthop Trauma Surg 127(2), 75–79. [Google Scholar]
  24. Meredith DS, Healey JH (2011) Twenty-year follow-up of monostotic fibrous dysplasia of the second cervical vertebra. JBJS Case Connect 93(13), e74. [Google Scholar]
  25. Yao L, Eckardt JJ, Seeger LL (1994) Fibrous dysplasia associated with cortical bony destruction: CT and MR findings. J Comput Assist Tomogr 18(1), 91. [PubMed] [Google Scholar]
  26. Muthusamy S, Subhawong T, Conway SA, Temple HT (2015) Locally aggressive fibrous dysplasia mimicking malignancy: a report of four cases and review of the literature. Clin Orthop Relat Res 473(2), 742–750. [CrossRef] [PubMed] [Google Scholar]
  27. Shapeero LG, Vanel D, Ackerman LV, et al. (1993) Aggressive fibrous dysplasia of the maxillary sinus. Skeletal Radiol 22(8), 563–568. [PubMed] [Google Scholar]
  28. Kashima TG, Gamage NM, Ye H, et al. (2013) Locally aggressive fibrous dysplasia. Virchows Arch 463(1), 79–84. [CrossRef] [PubMed] [Google Scholar]
  29. Dorfman HD, Ishida T, Tsuneyoshi M (1994) Exophytic variant of fibrous dysplasia (fibrous dysplasia protuberans). Human Pathol 25(11), 1234–1237. [CrossRef] [Google Scholar]
  30. Hermann G, Garcia R. 2013. Exophytic fibrous dysplasia of the rib. Osteologiai Közlemények. Available from https://www.google.com/search?q=hermann+exophytic+fibrous+dysplasia+of+the+rib&rlz=1C1CHBD_frFR838FR840&oq=hermann+exophytic+fibrous+dysplasia+of+the+rib++&aqs=chrome..69i57.91767j0j7&sourceid=chrome&ie=UTF-8. [Google Scholar]
  31. Latham PD, Athanasouz NA, Woods CG (1992) Fibrous dysplasia with locally aggressive malignant change. Arch Orthop Trauma Surg 111(3), 183–186. [Google Scholar]
  32. Snieders MN, van Kemenade FJ, van Royen BJ (2009) Monostotic fibrous dysplasia of a lumbar vertebral body with secondary aneurysmal bone cyst formation: a case report. J Med Case Rep 3(1), 7227. [Google Scholar]
  33. Sharifudin MA, Zakaria Z, Awang MS, Mohamed Amin MA, Abd Aziz A (2016) A rare case of monostotic spinal fibrous dysplasia mimicking solitary metastatic lesion of thyroid carcinoma. Malays J Med Sci 23(1), 82–86. [Google Scholar]
  34. Lee SH, Han IH, Kang DW, Choi BK (2011) Cervical fibrous dysplasia presenting as a pathologic fracture in an older patient. J Kor Neurosurg Soc 50(2), 139–142. [CrossRef] [Google Scholar]
  35. Dang D, Baig MN, Christoforidis G, Chiocca EA, Gabriel J (2007) C2/C3 pathologic fractures from polyostotic fibrous dysplasia of the cervical spine treated with percutaneous vertebroplasty. Eur Spine J 16(3), 250–254. [CrossRef] [PubMed] [Google Scholar]
  36. Medow JE, Agrawal BM, Resnick DK (2007) Polyostotic fibrous dysplasia of the cervical spine: case report and review of the literature. Spine J 7(6), 712–715. [CrossRef] [PubMed] [Google Scholar]
  37. Mezzadri JJ, Acotto CG, Mautalen C, Basso A (1999) Surgical treatment of cervical spine fibrous dysplasia: technical case report and review. Neurosurgery 44(6), 1342–1346. [PubMed] [Google Scholar]
  38. Stompro BE, Alksne JF, Press GA (1989) Diagnosis and treatment of an odontoid fracture in a patient with polyostotic fibrous dysplasia: case report. Neurosurgery 24(6), 905–909. [CrossRef] [PubMed] [Google Scholar]

Cite this article as: Milon A, Polivka M, Larousserie F, Lot G, Ziza J-M & Laredo J-D (2019) Locally aggressive monostotic fibrous dysplasia of the cervical spine mimicking malignancy: a case report and literature review. SICOT-J 5, 34

All Tables

Table 1

Reported cases of cervical spine fibrous dysplasia presenting with a pathological fracture.

In the text

All Figures

thumbnail Figure 1

(a) Sagittal, (b) coronal and (c) axial CT-scan reformations of the upper cervical spine in a 30-year-old woman, showing the mixed appearance of the C2 vertebral body with a ground-glass appearance and osteolytic areas in the base of the odontoid process with a pathologic fracture (thin arrow) and in the inferior part of the vertebral body with partial destruction of the inferior endplate (thick arrow).
In the text
thumbnail Figure 2

T2-weighted, T1-weighted, T1-weighted with intra-venous contrast administration midline sagittal MR images of the cervical spine showing the low signal intensity of the C2 vertebral body and odontoid process (a, b), with enhancement after contrast administration (c), and a solution at the junction between the odontoid process and vertebral body (a–c).
In the text
thumbnail Figure 3

Percutaneous needle biopsy of C2 under fluoroscopic guidance with an anterolateral approach.
In the text

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.