Flashcards in Odontogenic Neoplasms Deck (53)
A ________ is a benign but locally aggressive neoplasm of odontogenic epithelial origin
microscopically, what do Ameloblastoma cells resemble?
Microscopically, cells resemble the ameloblasts of the enamel organ, but no enamel is produced
what is the Prevalence of ameloblastomas? what groups are at the highest risk for developing them?
A) While considered the most common odontogenic neoplasm, it only constitutes about 0.2% of oral pathology biopsy cases
B) No sex predilection
C) Wide age range, from 3rd to 7th decades
Clinical characteristics of Ameloblastomas:
1) Most (80-85%) occur in the mandible, usually the molar-ramus region
2) About 20% are associated with an impacted tooth
3) Lesion grows slowly, destroying tissue, but usually expanding rather than perforating bone
Radiographic features of Ameloblastomas:
A) A small lesion usually presents as a unilocular radiolucency with well-defined borders
B) As the lesion progresses, the classic multilocular expansile radiolucency frequently develops
what are the characteristics of the "desmoplastic variant" Ameloblastoma?
A) Described initially in 1984
B) Distinctive radiologically as well as histologically
C) Radiographs usually show a poorly demarcated radiolucency with numerous radiopaque flecks
B) Similar in appearance to benign fibro-osseous lesion
Histological characteristics of Ameloblastomas:
1) Several different patterns, follicular and plexiform are most common
2) Small tumor islands which show cuboidal or columnar cells at their periphery
3) The center of the tumor islands is composed of loosely arranged polyhedral epithelial cells that resemble stellate reticulum
what is the treatment protocol for Ameloblastomas?
Depends on the size and site of the lesion
1) Small lesion - aggressive curettage or small en bloc resection
2) Large lesion - large en bloc resection or marginal segmental resection with reconstruction
what is the prognosis for Ameloblastomas?
- Prognosis: Guarded
1) With simple curettage, recurrence rates reported to be 50-90%
2) Even with marginal resection, recurrence rates up to 15%
3) Maxillary lesions warrant more aggressive surgical removal due to their anatomic location
what is the clinical presentation for Peripheral Ameloblastomas?
present as an asymptomatic gingival mass in a middle-aged adult, usually mandible
Typically less than 2 cm in diameter
T/F: Peripheral Ameloblastomas can easily be cured by local excision, and have little tendency to recur
what is the Histogenesis of Calcifying Epithelial Odontogenic Tumors?
Thought to be derived from cells of the stratum intermedium
what population groups are at the highest risk for Calcifying Epithelial Odontogenic tumors? where do most arise?
1) Mean age at diagnosis - 40 years, with no sex predilection
2) Most arise in the posterior mandible
3) Asymptomatic; swelling may be noted
4) 50% associated with an impacted tooth
Calcifying Epithelial Odontogenic tumors are also known as _______ tumors
radiographic findings for Calcifying Epithelial Odontogenic tumors:
A) Diffuse or well-circumscribed radiolucency unilocular when small
B) With growth, lesion may become multilocular
C) Radiopaque flecks often develop as lesion enlarges
histological findings for Calcifying Epithelial Odontogenic tumors:
1) Sheets or strands of polyhedral epithelial cells with eosinophilic cytoplasm
2) The nuclei are frequently pleomorphic, but mitoses are rare
in what material does calcification occur in Calcifying Epithelial Odontogenic Tumors?
Calcifications develop in a unique amyloid material
The lamellated structures formed in Calcifying Epithelial Odontogenic Tumors are called "________rings"
when would an Adenomatoid Odontogenic Tumor extend apically past the CEJ?
When associated with an impacted tooth
How can a Adenomatoid Odontogenic Tumor be differentiated from a dentigerous cyst?
you can see the Adenomatoid Odontogenic Tumor extend Apically beyond the CEJ
Histological features of Adenomatoid Odontogenic tumors:
1) Well-encapsulated lesion
2) The tumor cells form swirling spindle-cell nests with duct-like structures of varying sizes
3) Foci of basophilic calcified material may also be seen
what population groups are at risk for Adenomatoid Odontogenic tumors? where do these lesions occur?
A) Usually arises in a younger patient, mean age - 18 years, with 75% under 20 years of age
B) 2:1 female predilection
C) 2:1 maxillary predilection
D) 75% of these lesions develop in the anterior jaws, 75% are associated with an impacted tooth
General radiographic features of Adenomatoid Odontogenic tumors:
1) Well-circumscribed unilocular radiolucency that may contain radiopaque flecks
2) Separation of roots or displacement of adjacent teeth occurs frequently
Ameloblastic Fibromas are often found in what population groups? where are they usually found?
A) Younger patients: 1st – 2nd decades of life
B) Posterior mandible - (70% of cases)
T/F: the only clinical symptom of Ameloblastic fibromas is painless swelling
radiographic findings of Ameloblastic Fibromas:
Unilocular when small
Larger lesions can become multilocular
Margins tend to be well-defined
list the histological features of Ameloblastic Fibromas:
A) Myxoid connective tissue that resembles dental papilla that contains strands and islands of odontogenic epithelium that resembles dental lamina
B) Connective tissue resembles dental papilla
C) Epithelial islands can resemble follicular or plexiform ameloblastoma
what is the prognosis/treatment for Ameloblastic Fibromas?
1) Treatment consists of aggressive curettage
2) Prognosis: good
3) Recurrence rate is low (0-18%)
4) Rare malignant transformation
what is a "Ameloblastic Fibro-Odontoma"?
Odontogenic tumor with features of ameloblastic fibroma as well as odontoma