Teratomas of the Head and Neck

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Teratomas of the Brain and
Head and Neck
Grimme JD, Camacho DLA, Spampinato MV,
Castillo M
Section of Neuroradiology
Department of Radiology
University of North Carolina
We present examples of teratomas found
in the brain and extracranial head and
neck taken from our teaching files,
collected over a 10-year period. Along
with the imaging findings we discuss
important
clinical
and
pathological
information regarding these lesions.
Because of the presence of cysts and
calcifications, both CT and MRI provide
critical information that helps in formulating
a differential diagnosis.
Histologic Classification
• Mature
type:
composed
of
fully
differentiated adult-type tissues, absent or
low mitoses
• Immature type: fetal-type incompletely
differentiated tissues
• Malignant type: contains cancerous
tissues such as sarcomas, carcinomas
and other embryonal malignancies
Tumor Markers
• Malignant yolk sac endoderm can be an
aggressive component of teratomas and
these patients may have elevated levels of
AFP or beta-HCG in serum and/or CSF
• Transcription factors GATA-4 and GATA-6
may also be elevated in mature and
immature teratomas
Clinical Features
• 90% of teratomas are found below 20
years of age (most: 10-12 years)
• Male-to-female ratio: 2.5:1
• 80% occur around region of 3rd ventricle;
thus most symptoms are due to
hydrocephalus and increased intracranial
pressure
General Imaging Features of
Teratomas
• Heterogeneous appearance
– Presence of fat, cysts (mucous-laden),
calcium (bone and chondroid nodules), soft
tissues
• Enhancing soft tissues
– Present in all types of tumors
– Enhancement of capsule
– Heterogeneous enhancement of soft tissue
components
Congenital Teratoma
Intracranial
teratomas
are rare, accounting for
0.5-2.0% of intracranial
tumors. They comprise
50% of congenital brain
tumors (those presenting
in the first 60 days of
life).
Above: Contrast enhanced CT of congenital teratoma shows a centrally
located heterogeneous mass containing cystic/solid components and
severe hydrocephalus.
Congenital Teratoma
Teratomas
are
typically
benign tumors containing
elements of all 3 germinal
layers: ectoderm, mesoderm
and endoderm. They develop
from embryonic cells which
become “misinvolved” during
formation of the primitive
streak in the 3rd week of life.
Some of these cells become
“misenfolded” as intracranial
rests of tissue.
Above: Axial T1 (left) and T2 (right) images of a congenital teratoma
(arrows). The mass is centrally located and has a heterogeneous
appearance. There is hydrocephalus.
Pineal Teratoma
Tissue rests are typically found in the midline, specifically, the pineal,
suprasellar and 3rd ventricle regions.
Above: Contrast enhanced CT (left) and pre- (middle) and post-Gd (right) T1
images. There is peripheral enhancement on CT (arrows) and mild
heterogeneous enhancement (arrows) on MRI. Ventricular air was introduced
by a ventriculostomy.
Pineal Teratoma
Another example of pineal teratoma seen on sagittal T1 (left), axial post-Gd
T1 (middle) and axial T2 (right) images. There is heterogeneous signal from
cystic and solid components, capsular (arrow) and tumoral enhancement.
Suprasellar Teratoma
Differential diagnosis for a T1 bright and T2 dark includes
aneurysm, dermoid, lipoma and craniopharyngioma.
Above: Coronal T1 (left) and T2 (right) images of a
suprasellar teratoma with considerable fatty contents.
Suprasellar Teratoma
Large suprasellar mostly cystic mass (left: T1 coronal, right: T2
axial) initially believed to be a craniopharyngioma but proven to
be a teratoma.
Suprasellar Teratoma
Intracranial
teratomas
usually
manifest
in
younger children – adult
presentation is unusual.
Left: Suprasellar teratoma
in a child. Axial FLAIR
(top left) and T2 (top right)
images
show
bright
lesion. T1 sagittal images
without (bottom left) and
with (bottom right) Gd
show
heterogeneous
enhancement of mass.
Suprasellar Teratoma
Example of childhood suprasellar teratomas. Axial
non-contrast CT (left) and sagittal T1 image (right)
demonstrate fat (arrows) in both lesions.
Intraventricular Teratoma
Axial non-contrast CT (left), axial T2 (middle) and coronal post-Gd T1
(right) images in intraventricular teratoma.
Fat, cysts and
calcifications (arrows) are present.
The tumor shows central
heterogeneous enhancement. Note associated hydrocephalus.
Cerebellar Teratoma
Teratomas are classified by cell/tissue types as mature or immature, and
graded histologically from 0-3, with grade increasing with amount of
immature tissues. Grade 0: only mature tissues. Grade 3: large amounts of
immature tissues.
Above: Cerebellum is an unusual location for teratoma. Axial contrast
enhanced CT (left), axial T2 (middle) and sagittal T1 (right) images show a
heterogeneous mass containing fat (arrows).
Facial Teratoma
Differential diagnosis for a facial teratoma includes lymphatic malformation,
arteriovenous malformation, hemangioma, neuroblastoma, and dermoid
cyst.
Above:
Axial T1 pre- (left) and post-Gd (right) images show a
heterogeneous cystic mass in the region of the left parotid tail with a
heterogeneously enhancing solid component (arrows).
Facial Teratoma
Axial T2 (left), axial T1 (middle) and sagittal T1 (left) images of a heterogeneous
mass in the left facial region with cystic and solid components, which proved to
be a teratoma.
Facial Teratoma
Head and neck teratomas commonly occur in the anterior midline, usually in
the oropharynx or nasopharynx, but may also involve the orbit, temporal fossa,
and face. Some teratomas, especially those arising in the nasopharynx, may
traverse the skull base and have extensive intracranial extension.
Above: Axial CECT of a child with a large exophytic heterogeneous mass,
which was originating from the oropharynx. Note the presence of fat adjacent
to the coarse calcifications (arrow). C/O Dr. Bernadette Koch
Upper Neck Teratoma
Cervical teratomas typically present at birth as firm ovoid masses with
palpable cystic areas.
Calcifications are seen on plain radiographs in up to 45% of teratomas.
Above: Lateral radiograph (left) shows coarse calcifications (arrow) in an
anterior upper neck teratoma in a child. Axial CT images (middle and right)
of the same patient show macroscopic fat (arrows) in addition to the
calcifications.
Upper Neck Teratoma
Presenting symptoms of cervical teratomas include respiratory distress,
feeding difficulties and torticollis.
Axial CECT image of the upper neck shows a large complex mass on the
right side with cystic components and heterogeneous enhancement. Note
presence of endotracheal tube. C/O Dr. Bernadette Koch
Cervical Teratoma
Above: Post-contrast axial CT image (left) and ultrasound image (right) of a
cervical teratoma. Note tracheal narrowing and deviation, and presence of
calcification seen in both studies (arrows).
Lower Neck Teratoma
Teratomas comprise 9% of head and neck tumors in children.
Above: Radiograph (left) and axial CT image (right) of a teratoma arising
from the region of the thyroid gland, extending inferiorly into the superior
mediastinum. Note leftward tracheal deviation and coarse calcifications
within the mass on the CT image (arrow).
Conclusion
Teratomas involving the head and neck
are rare tumors characteristically involving
the midline, nearly always having a
heterogeneous appearance and often
containing fat and/or calcifications.
References
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