SPINE Volume 25, Number 8, pp 1036 –1039
©2000, Lippincott Williams & Wilkins, Inc.
Intraosseous Calcifying Pseudotumor of the Axis
A Case Report
Han Chang, MD,* Jong-Beom Park, MD,* and Ki-Won Kim, MD†
Study Design. A case report and review of the literature.
Objective. To present the first case of intraosseous
calcifying pseudotumor arising from the axis.
Summary of Background Data. Calcifying pseudotumor is a very rare disease. Only 24 cases have been
previously reported.
Methods. A case of calcifying pseudotumor involving
the body, dens, and laminae of the axis in a 60-year-old
male patient was managed with total laminectomy of the
axis and instrumented occipitocervical fusion, followed
by the curettage of the body and dens of the axis and
autogenous iliac bone graft. Medical records, imaging
studies, microscopic findings, and related literature are
reviewed.
Results. Microscopic examination showed amorphous, basophilic, and chondroid calcifying masses surrounded with palisading histiocytes and foreign bodytype giant cells. The findings were consistent with those
of calcifying pseudotumors previously reported in other
sites of the body. At 24 months after operation, a significant reduction of neck pain was achieved. But there was
evidence of local recurrence of the lesion in the body and
dens of the axis with a local progression of the preexisting lesion in the facet joints.
Conclusion. This is the first report of intraosseous calcifying pseudotumor arising from the axis. [Key words:
intraosseous calcifying pseudotumor, axis] Spine 2000;
25:1036 –1039
Calcifying pseudotumor is extremely unusual. Previous
reports of the lesion have been described under the designation of fibroosseous lesions and calcifying pseudoneoplasm in skull base,1 intracranial parenchyme,3,9,13
soft tissue around the spinal cord,1,10 mediastinum,8 and
pleura.12 However, no reports have been previously published on the calcifying pseudotumor arising from the
intraosseous region of the spine. In the present report,
the authors describe the first case of calcifying pseudotumor involving the intraosseous region of the axis.
CASE REPORT
A 60-year-old man was referred to the authors’ department with a 4-year history of a slowly progressive neck
From the *Department of Orthopaedic Surgery, Uijongbu St. Mary’s
Hospital, College of Medicine, The Catholic University of Korea,
Kyunggi-do, Korea, and the †Department of Orthopaedic Surgery, St.
Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
This study was supported by a grant from the Catholic Medical Center,
The Catholic University of Korea, Seoul, Korea.
Acknowledgment date: December 15, 1998.
First revision date: March 29, 1999.
Acceptance date: July 27, 1999.
Device status category: 3.
Conflict of interest category: 12.
1036
pain and a limited range of neck motion. A calcifying
lesion involving the body, dens, and laminae of the axis
had been incidentally identified with plain radiographs
of the cervical spine at another hospital 4 years ago (Figure 1) and was checked serially with plain radiographic
films. At the time of referral, the patient complained of
severe neck pain7 without neurologic abnormalities. The
range of neck motion was limited due to pain: flexion,
25°; extension, 15°; lateral bending to both sides, 15°;
axial rotation to both sides, 10°. The lateral radiographic
film of the cervical spine showed some enlargement of
the radiolucent lesion and an increase in multiple calcifications in the body, dens, and laminae of the axis when
compared with those of the initial plain radiographic
film (Figure 2). Bone scintigraphy showed an increased
isotope uptake around the axis. T1- and T2-weighted
and Gadolinium-enhanced magnetic resonance images
(MRIs) were obtained with a 1.5 tesla superconductive
unit. A sagittal T1-weighted MRI showed masses with
slightly low signal intensity in the body, dens, and laminae of the axis, where multiple foci with dark signal
intensity of the masses were scattered (Figure 3A). The
masses on sagittal T2-weighted MRI also showed diffuse
low signal intensities and mild dural compression (Figure
3B). A sagittal Gadolinium-enhanced MRI showed an
enhancement in the body, dens, and laminae of the axis,
except multiple foci with dark signal intensity. However,
no soft tissue involvement, spinal cord compression, and
cortical perforation were shown (Figure 3C). At first, to
provide for the space that can prevent mechanical compromise of the neural tissue by progressive expansile lesion of the body and dens of the axis, total laminectomy
of the axis and occipitocervical fusion with a Cotrel–
Dubousset rod system (Sofamor-Danek, Roissy, France)
was performed through the midline posterior approach.
The operative findings were the thinned bony cortexes of
spinous process and laminae, which was slightly expanded but not perforated and was occupied with yellowish gray rubbery materials. Microscopic examination
showed amorphous, basophilic, and chondroid-calcifying masses surrounded with palisading histiocytes and
foreign body-type giant cells. No evidence of malignancy
was found (Figures 4A and 4B). One month after the
posterior operation, the curettage of the body and dens
of the axis and autogenous iliac bone graft were performed through the left side anterior approach. Postoperatively, a Minerva cast was put on the patient. By postoperative 3 months, a solid bony union of the
occipitocervical fusion mass was achieved and a Minerva
cast was removed. According to the method of the Visual
Intraosseous Calcifying Pseudotumor • Chang et al 1037
Figure 1. The initial lateral radiographic film of the cervical spine
showing a poorly defined radiolucent lesion with multiple calcifications in the body, dens, and laminae of the axis.
Analogue Scale,7 the patient rated a significant improvement of neck pain. A lateral radiographic film taken at 24
months after operation showed evidence of local recurrence of the lesion in the body and dens of the axis with
a local progression of the preexisting lesion in the facet
joints (Figure 5).
DISCUSSION
Calcifying pseudotumor is a very rare disease. Only 24
cases have been reported since Rhodes and Davis13 first
described the lesion in the intracranial regions in 1978.
The reported locations of the lesion are skull base,1 intracranial parenchyme,3,9,13 soft tissue around the spinal
cord,1,10 mediastinum,8 and pleura.12 In 10 of the 24
Figure 2. The follow-up lateral radiographic film of the cervical
spine 4 years after the initial radiographs showing a slight enlargement of the radiolucent lesion, and an increased number of
calcification in the body, dens, and laminae of the axis when
compared with those of the initial radiographs.
cases, the lesions were developed in the spine; in 9, in the
epidural space; in 1, in the intradural extramedullary
space. However, no reports have been previously published on the calcifying pseudotumor arising from the
intraosseous region of the spine.
Figure 3. A, A sagittal T1-weighted MRI showing the masses with slightly low signal intensity in the body, dens, and laminae of the axis
and scattered multiple foci with a dark signal intensity. B, Sagittal T2-weighted MRI showing masses with diffuse low signal intensities
and mild dural compression. C, Sagittal Gadolinium-enhanced MRI showing enhancement in the body, dens, and laminae of the axis
except the multiple foci with dark signal intensity.
1038 Spine • Volume 25 • Number 8 • 2000
Figure 4. A, The photomicrograph of the lesion showing hyaline, basophilic, chondroid, and calcifying masses arranged in large plates
or fragmented small pieces (hematoxylin-eosin; magnification, ⫻40). B, The photomicrograph of the lesion showing the masses that are
surrounded with palisading histiocytes and foreign body-type giant cells (hematoxylin-eosin; magnification, ⫻100).
While the etiology, pathogenesis, and natural course
of the lesion remain unclear, a calcifying pseudotumor
has been regarded as benign reactive rather than neoplastic.1,9 In the present report, the benign nature of the
lesion can be assumed by very slow enlargement of the
lesion, low signal intensities of the masses on both T1and T2-weighted images, no surrounding soft tissue involvement, and the cortical thinning without perforation. Pathologic specimens also showed a benign nature:
amorphous, basophilic, and chondroid calcifying lesions
surrounded with palisading histiocytes and foreign
body-type giant cells. This granuloma-like feature is a
characteristic finding of a calcifying pseudotumor, which
can provide a definite clue for the diagnosis of the lesion.1,2,9,15
Operative management of the lesion varies from debulking to wide excision. In three of the previous reports,
the lesion recurred locally, following intralesional or
marginal excision and bone graft.1,2 However, the prognosis was favorable due to the lesion’s benign and nonneoplastic nature irrespective of the extent of operation
and local recurrence of the lesion.1,2 In the present report, since the progressive expansile lesion involved the
entire intraosseous region of the axis, the patient was
managed with total laminectomy of the axis and occipitocervical fusion with a Cotrel–Dubousset rod system
followed by the curettage of the body and dens of the
axis and autogenous iliac bone graft. A solid bony union
of the occipitocervical fusion mass was achieved and
neck pain was improved significantly according to the
method of the Visual Analogue Scale.7 But there was
evidence of local recurrence of the lesion in the body and
dens of the axis with a local progression of the preexisting lesion in the facet joints at the most recent follow-up
of 24 months after operation. Therefore, it is believed
that the lesion should be checked carefully to clarify the
necessity of a future second anterior surgery for a period.
There are several types of fixation4,5,14 for nontraumatic upper cervical instability, including tumoral exten-
sion and rheumatoid arthritis. Among them, Cotrel–
Dubousset rod system have several advantages in spite of
a possible risk for spinal cord injury caused by hooks
inserted into the cervical spinal canal.6,11 Because the
authors performed the staged posterior and anterior operations in this case, reasonable indications and appropriate timing for surgery of similar cases cannot be
answered. In addition, this first case of calcifying pseudotumor arising from the axis cannot provide dependable
information as to whether the lesion is mechanically stiff
or not. In the current case, the authors thought that the
Figure 5. A lateral radiographic film of the cervical spine taken at
24 months after operation showing a solid bony union of the
occipitocervical fusion mass with evidence of local recurrence of
the body and dens of the axis and a local progression of the
preexisting lesion in the facet joints.
Intraosseous Calcifying Pseudotumor • Chang et al 1039
staged posterior and anterior operations was necessary
to prevent mechanical or neural compromise by the progressive expansile lesion of the body, dens, and laminae
of the axis in spite of a local recurrence rate of the lesion,1,2 patient’s age, and neurologic state before operation.
In summary, the first case of a calcifying pseudotumor
is reported arising from the intraosseous region of the
axis, in which the lesion’s histopathologic features were
consistent with those of calcifying pseudotumors previously reported in other sites of the body.
Acknowledgment
The authors thank Lars G. Gilbertson, Asst. Professor,
Department of Orthopedic Surgery, University of Pittsburgh, PA, for assisting in manuscript preparation.
7. Huskisson EC. Measurement of pain. Lancet 1974;2:1127–31.
8. Jeong HS, Lee GK, Sung R, Ahn JH, Song HG. Calcifying fibrous pseudotumor of mediastinum. A case report. J Korean Med Sci 1997;12:58 – 62.
9. Jun C, Burdick B. An unusual fibro-osseous lesion of the brain. Case report.
J Neurosurg 1984;60:1308 –11.
10. Moser FG, Tourje EJ, Pressman BD, Blinderman EE. Calcifying pseudotumor of the cervical spine (Letter). Am J Neuroradiol 1994;15(3):580.
11. Paquis P, Breuli V, Lonjon M, Euller-Ziegler L, Grellier P. Occipitocervical
fixation using hooks and screws for upper cervical instability. Neurosurgery
1999;44(2):323–31.
12. Pinkard NB, Wilson RW, Lawless N, et al. Calcifying fibrous pseudotumor
of pleura. Am J Clin Pathol 1996;105:189 –94.
13. Rhodes RH, Davis RL. An unusual fibro-osseous component in intracranial
lesions. Hum Pathol 1978;9:309 –19.
14. Roy-Camille R, Saillant G. Surgery of the cervical spine: 4-Osteosynthesis of
the upper cervical fusion utilizing a rectangular rod. Clin Orthop 1989;
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15. Smith DM, Berry AD III. Unusual fibro-osseous lesion of the spinal cord with
positive staining for glial fibrillary acidic protein and radiological progression: A
case report. Hum Pathol 1994;25(8):835– 8.
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Address reprint requests to
Jong-Beom Park, MD
Department of Orthopaedic Surgery
Uijongbu St. Mary’s Hospital
College of Medicine
The Catholic University of Korea
65–1 Kumho-dong, Uijongbu-si
Kyunggi-do, 480 –130 Korea
E-mail: spinepjb@cmc.cuk.ac.kr