Advances in Computed Tomography, 2013, 2, 1-3 Published Online March 2013 (
Early Initial Diagnosis of Gardner Syndrome in a
12-Year-Old Boy
Erich Bryan, Peter Kalina
Mayo Clinic, Rochester, USA
Received December 6, 2012; revised January 6, 2013; accepted January 16, 2013
A 12-year-old boy presented to his primary care physician with a painful lump at the angle of the left mandible after
being kicked in the jaw during a soccer game. Over the next 2 months the lesion became progressively firmer and fine
needle aspiration was attempted. Results were non-diagnostic. Panorex examination revealed a calcified mass contiguous
with the left angle of the mandible. Considerations were bony callus secondary to trauma versus a calcified hematoma.
A maxillofacial CT showed multiple diffuse craniofacial osseous lesions including the clin ically suspected reg ion at the
left angle of the mandible. Imaging findings were consistent with multiple craniofacial osteomas and workup for Gard-
ner Syndrome was initiated. Genetic testing was subsequently positive for Familial Adenomatous Polyposis.
Keywords: Gardner Syndrome; Osteoma
1. Introduction
Gardner Syndrome is a rare variant of Familial Adeno-
matous Polyposis (FAP) caused by a gene mutation on
chromosome 5 [1]. Gardner syndrome is defined as a
triad of intestinal polyps and extraintestinal manifesta-
tions including osteomas and tumors of the skin and soft
tissue. Incidence of Gardner syndrome is between 1 in
4000 and 1 in 12,000 [2]. A hereditary form of colonic
polyposis was described by Cripps in 1863. Gardner
syndrome was ultimately defined by Gardner in 1950
who later recognized the dental and skeletal abnormali-
ties of the disease [2]. The diagnosis portends significant
morbidity. Ninety percent of patients with Gardner Syn-
drome will have intestinal polyps which, in turn, have a
nearly one hundred percent chance of malignant trans-
formation. Prophylactic colectomy including rectal re-
section is recommended when patients have 30 or more
intestinal polyps [2]. Benign osteomas usually precede
the development of intestinal polyposis and soft tissue
tumors [1]. The following case report attempts to dem-
onstrate the importance of early detection of the disease
and how radiologists can aide in early detection with
knowledge of the extra-intestinal manifestations and their
presentat i on on imagi ng.
2. Case Report
A 12-year-old boy was kicked in the jaw during a soccer
game and presented to his primary care physician and
subsequently to an ear nose and throat specialist with
Figure 1. Clinical Photographs of the left mandibular angle
opyright © 2013 SciRes. ACT
complaint of a painless lesion at the angle of the left
mandible that appeared to be getting progressively firmer
over a two month period (Figure 1). The left mandibular
angle lesion and multiple other similar lesions were con-
firmed on CT to be maxillofacial osteomas. Workup for
Gardner Syndrome was initiated and genetic testing was
3. Discussion
Gardner Syndrome is a variant of Familial Adenomatous
Polyposis. It is an early onset autosomal dominant ge-
netic that can affect both sexes. Intestinal polyps can
occur anywhere in the digestive tract, most commonly in
the colon. These po lyps must be completely removed du e
to the high rate of malignant degeneration [2]. The aver-
age age of diagnosis of intestinal polyps is 22 years
though they typically develop at about the time of pu-
berty. Progression to malignancy is typically seen be-
tween ages 30 to 60 years [3].
Extra-intestinal manifestations typically precede the
intestinal polyps and can include bone lesions (benign
osteomas), thyroid carcinoma, connective tissue tumors,
and pigmentation of the retina. Soft tissue tumors can
include neurofibromas, fibromas, keloids, sebaceous
cysts, leiomyomas, lipomas, and desmoid tumors [2].
Osteomas are benign tumors of compact bone that show
continuous osseous growth. They are required to make
the diagnosis of Gardner Syndrome. These tumors will
most frequently be seen involving the teeth, facial bones,
and cranium. These lesions are not commonly painful
and they are typically removed only for aesthetic reasons
or due to limitations in mandibular movement. A typical
location for an osteoma is at the angle of the mandible, as
in the case presented above [1].
Computed Tomography (CT) is often utilized as the
initial imaging modality for the evaluation of potential
maxillofacial disease processes. This is true for bo th soft
tissue disease such as such as inflammatory changes as
well as osseous abnormalities. CT is preferred due to its
increased availability, decreased cost and ability to pro-
vide excellent, often superior osseous detail. In our case,
a potential focal hematoma or mandibular lesion were
suspected due to the trauma history. For both of these
indications, CT would be the preferred modality.
This patient’s CT scans of the face (including coronal
and sagittal reformatted images) demonstrates multiple
maxillofacial osteomas including the area of palpable
abnormality over the angle of the left mandible where the
patient was kicked during his soccer game as well as a
large ethmoid lesion (Figures 2 and 3). 3D surface re-
formatted images confirm and further delineate the extent
of the osteomas (Figure 4). The association of multiple
maxillofacial osteomas with Gardner syndrome was rec-
Figure 2. Coronal and Sagittal CT showing left mandibular
angle osteoma.
Figure 3. Coronal and Sagittal CT showing mutiple addi-
tional craniofacial osteomas including a large ethmoid le-
Figure 4. 3D Reformatted CT showing left mandibular and
large ethmoid osteomas.
ognized and workup for the disease was initiated. The
patient’s genetic workup was positive for the variant of
Familial Adenomatous Polyposis (FAP). He was then
referred to the appropriate services for further screening
and management.
In conclusion benign osteomas usually precede the
development of intestinal polyposis and soft tissue tu-
mors [1]. Therefore, the radiologist and dentist can diag-
nose early Gardner Syndrome and help initiate workup
with genetics, gastroenterology, oncology, and oral/ma-
xillofacial surgery to hopefully prevent morbity and
Copyright © 2013 SciRes. ACT
Copyright © 2013 SciRes. ACT
mortality associated with the disease.
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Olgac, C. Kasapoglu and C. K. Oral, “Oral and Maxillo-
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tional Journal of Medical Science, Vol. 9, No. 2, 2012, pp.
[2] U. Bilkay, O. Erdem, C. Ozek, E. Helvaci, K. Kilic, Y.
Ertan and T. Gurler, “Benign Osteoma with Gardner Syn-
drome: Review of the Literature and Report of a Case,”
Journal of Craniofacial Surgery, Vol. 15, No. 3, 2004, pp.
[3] M. Brucoli, M. Giarda and A. Benech, “Gardner Syn-
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Craniomaxillofacial Osteomas,” Journal of Craniofacial
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