Odontogenic Neoplasms Flashcards
What are the three tumors of odontogenic epithelium?
- ameloblastoma - peripheral ameloblastoma
- adenomatoid odontogenic tumor
- calcifying epithelial odontogenic tumor (CEOT, Pindborg tumor)
What are three mixed odontogenic tumors?
- ameloblastic fibroma
- ameloblastic fibro-odontoma
- Odontoma
What are two tumors of odontogenic ectomesenchyme?
- odontogenic myxoma
2. cementoblastoma
Ameloblastoma is a ___ but locally aggressive neoplasm of odontogenic epithelial origin that histologically resembles the ameloblasts of the ___ ___, but no ___ is produced by lesional cells.
benign; enamel organ; enamel
T/F. The frequency of ameloblastoma equals the combined frequency of all other odontogenic tumors.
True.
Even tho ameloblastoma is among the more common of the odontogenic neoplasms, it still constitutes only about ___ % of oral pathology accessions.
0.2%
T/F. Ameloblastoma is commonly seen in women around the age of 20.
False, ameloblastoma has NO SEX predilection and is diagnosed around 33 years of age.
Most ameloblastomas occur in the ___ usually in the ___-___ region and about ___% are associated with an ___ tooth.
mandible; molar-ramus; 20%; impacted
T/F. Ameloblastomas are fast-growing lesions that destroy tissue by perforating bone.
False, Ameloblastomas are SLOW growing lesions that destroy tissue by expanding (very dramatically) rather than perforating bone.
T/F. Typically ameloblastomas are asymptomatic except for swelling.
True.
T/F. Ameloblastomas are small lesions that present as unilocular radiolucencies with well-defined, sclerotic borders.
False, Ameloblastomas are small lesions that present as unilocular radiolucencies with well-defined, but NOT sclerotic borders.
As ameloblastomas progress, the classic multilocular, expansile radiolucency develops, known as “___ ___” or “___”. They may displace teeth and/or resorb roots
soap bubble; honeycomb
What are the most often seen forms of ameloblastoma?
follicular and plexiform
Ameloblastomas have small tumor ___ and show a single layer of tall ___ or ___ cells at their periphery with ___ ___. What does this mean?
islands; reverse polarization
the nuclei are polarized away from the basement membrane
What is found in the center of an ameloblastoma’s tumor islands?
loosely arranged polyhedral epithelial cells that resemble stellate reticulum
How is ameloblastoma treated?
depends on size
small: aggressive curettage or small en bloc resection
large: en bloc resection or segmental resection with reconstruction
___ ameloblastomas are treated more aggressively due to their anatomic location near the sinus.
Maxillary
Prognosis of ameloblastoma is guarded because with simple curettage, recurrence is reported to be ___-___%. Even with marginal resection, recurrence rates up to ___% have been reported.
55-90%; 15%
T/F. Ameloblastomas can be fatal, especially with lesions in the maxilla. Malignant transformation is rare and ameloblastoma requires follow-up for 8-10 years.
Both statements are true.
What is a soft tissue variant of ameloblastoma that has no or limited bone involvement, no radiographic findings, is asymptomatic and presents as a gingival mass in middle-aged adults, usually in the mandible?
peripheral ameloblastoma
Peripheral ameloblastoma looks like many gingival ___, is less than ___cm in diameter and can be cured with ___. It has little tendency to recur.
bumps; 2; biopsy
What disease is a asymptomatic swelling discovered incidentally whose histogenesis is enamel organ or dental lamina rests?
Adenomatoid Odontogenic Tumor
T/F. AOT is seen in the mandible of male patients over 20
False, AOT is seen in the MAXILLA of FEMALE patients UNDER 20
What percentage of AOTs are found in the anterior jaws? What percentage of AOTs are associated with an impacted tooth?
75%
75%
AOTs are well-circumscribed (capsule) unilocular radiolucencies that may contain radiopaque ___. Separation of the roots or displacement of adjacent teeth occurs ___ (rarely/frequently). Percoronal lucency may extend apically beyond the ___.
flecks; frequently; CEJ
T/F. AOTs have a well-developed capsule.
True
AOT cells form swirling spindle-cell nests that contain duct-like structures of varying sizes known as ___.
adenomatoid
T/F. In addition to adenomatoid, foci of basophilic calcified material may be seen with AOTs.
True
How are AOTs treated and what is the prognosis and recurrence rate?
tx: enucleation
prognosis: excellent
recurrence: very rare
What is a rare odontogenic epithelial neoplasm that was initially described by Pindborg in 1956 and probably confused with ameloblastoma prior to that time?
CEOT (Pindborg Tumor)
What is the histogenesis of CEOT?
stratum intermedium
What is the mean age of diagnosis and sex predilection of CEOT?
40 years with no sex predilection
What is the predominance of the mandible compared to the maxilla in CEOT? What segment predominates?
2:1
posterior
T/F. In CEOT, if symptoms are present they usually consist only of swelling in the area.
True.
T/F. Unlike AOT, CEOT is not associated with an impacted tooth.
False, CEOT is often associated with an impacted tooth
CEOT is a well-circumscribed radiolucency when small that becomes ___ when it enlarges. Radiopaque ___ may or may not be seen. The ___ are usually well-defined but can be ill-defined.
multilocular; flecks; margins
CEOT has proliferation of ___ epithelial cells with eosinophilic cytoplasm. The nuclei are frequently ___ but mitosis is rarely observed.
polyhedral; pleomorphic
How do eosinophilic, homogeneous materials associated with epithelial cells of CEOT stain?
amyloid
In CEOT, calcifications may develop in the ___ material, forming lamellated structures called ___ ___.
amyloid; Liesegang rings
T/F. CEOT is treated with radical surgery due to its high recurrence rate.
False, Conservative excision is done. The recurrence rate is 15% so radical surgery is not warranted
What is the odontogenic origin of ameloblastic fibroma?
Mixed odontogenic origin of epithelial and ectomesenchymal tissues
T/F. Both tissues of ameloblastic fibroma are neoplastic.
True.
Ameloblastic fibromas have proliferating odontogenic epithelium in a cellular ectomesenchyme resembling the ___ ___.
dental papilla
Ameloblastic fibromas are found in younger patients during the first ___ decades of life and in the ___ mandible in ___% of cases.
two; posterior; 70
Small ameloblastic fibroma lesions are ____ (symptomatic/asymptomatic), while larger ones produce ___ swelling.
asymptomatic; painless
T/F. When small, ameloblastic fibromas are unilocular and tend to become multilocular when large. The margins can be either well-defined or sclerotic.
Both statements are true.
Ameloblastic fibromas have ___ connective tissue that resembles dental ___ that contains strands and islands of odontogenic epithelium that resembles dental ___.
myxoid; papilla; lamina
T/F. Sometimes the epithelial islands of an ameloblatic fibroma are large enough to vaguely resemble ameloblastoma.
True.
What is the treatment and the prognosis and recurrence rate of ameloblastic fibroma? Does it become malignant?
tx: aggressive curettage
prognosis: good
recurrence rate: low (15%)
rare malignant transformation
What disease is an odontogenic tumor with features of ameloblastic fibroma admixed with an odontoma?
Ameloblastic Fibro-Odontoma
When is Ameloblastic Fibro-Odontoma usually diagnosed?
in children, average age of 10 yrs
When is Ameloblastic Fibro-Odontoma symptomatic?
when there is failure of tooth eruption is noted or swelling is observed with large lesions.
T/F. Ameloblastic Fibro-Odontoma occurs more frequently in the mandible. It often overlies an impacted tooth.
1st statement is false, 2nd is true
Ameloblastic Fibro-Odontoma occurs equally in mandible and maxilla
Ameloblastic Fibro-Odontoma is a well-circumscribed, unilocular or multilocular radiolucency with varying amounts of calcified material having the density of ___ ___.
tooth structure.
What type of Odontoma is usually associated with Ameloblastic Fibro-Odontoma?
complex odontoma
What is the treatment and the prognosis and recurrence rate of Ameloblastic Fibro-Odontoma?
tx: conservative curettage
prognosis: excellent
recurrence: unusual
T/F. Odontoma is a true neoplasm.
False, it is probably not a true neoplasm, but rather an odontogenic hamartoma
What and where are the two forms of an Odontoma?
compound - anterior jaw
complex - posterior jaw
Odontoma ar most detected during the first ___ decades of life with a mean age of ___ years.
two; 14
Odontomas are associated with an ___ tooth and it is slightly more frequent in the ___.
unerupted; maxilla
Describe a compound odontoma.
A collection of small malformed teeth surrounded by a narrow radiolucent rim, often overlying an impacted tooth.
Describe a complex odontoma.
A calcified mass, that, if fully formed, has the density of tooth structure. It is also surrounded by a narrow radiolucent rim, typically overlying an impacted tooth.
The complex odontoma shows a admixture of what?
dentin, enamel matrix, cementum, odontogenic epithelium and dental papilla
How is an odontoma treated and what is its prognosis?
tx: enucleation
prognosis: excellent
An odontogenic myxoma is considered a ___ neoplasm of odontogenic origin because it only affects the ___ bones as a central lesion - no other bones.
benign; jaw
Odontogenic myxoma affects ___ adults (average age ___-___ years), but it is seen over a wide age range.
young; 25-30
What jaw is more affected in odontogenic myxoma?
mandible
T/F. Larger odontogenic myxoma lesions are symptomatic with expansion of the bone.
False, they are asymptomatic with expansion of the bone
When small, odontogenic myxomas are ___ and ___ when large. They may have a “___ ___” appearance and can displace and resorb ___.
unilocular; multilocular; soap bubble; roots
Odontogenic myxomas have thin, ___ trabeculae of residual bone often at ___ ___.
wispy; right angles
Odontogenic myxomas have ___-shaped or ___-shaped fibroblastic cells set in a ___ background.
spindle; stellate; myxoid
The lesion proliferation seen in odontogenic myxoma tends to infiltrate the adjacent bony trabeculae and this contributes to what?
recurrence rate, especially if only treated with curettage
How are small and large lesions of odontogenic myxomas treated?
small - curettage
large - en bloc or segmental resection, depending of the size and site.
What is the prognosis and recurrence rate of odontogenic myxomas?
prognosis: good
recurrence rate: up to 25%
What disease has very pathognomonic radiographic features?
cementoblastoma
Cemetoblastoma is a well-circumscribe radiopaque ___ with a fine radiolucent border. It is ___ to the resorbed root of a tooth usually a ___ ___ ___, usually obscures the outline of the root.
mass; fuses; mandibular first molar
Cementoblastomas have trabeculae of mineralized material that resembles ___ and are rimmed by plump, ___ cells that represent neoplatic ___.
cementum; angular; cemntoblasts
What are two differential diagnoses for cementoblastoma?
How is the cementoblastomas distinguishing feature?
osteoblastoma, osteosarcoma
fused to root
How is cementoblastoma treated?
surgical extraction of the involved tooth with enucleation of the lesion OR the tooth can be endodontically treated and the lesion enucleated along with amputation of the involved root
What is the prognosis of cementoblastoma?
excellent
