Odontogenic Neoplasms - part I Flashcards
odontogenic neoplasms
- tumors of odontogenic epithelium
- mixed tumors of odontogenic epithelium and odontogenic ectomesenchyme
- tumors of odontogenic ectomesenchyme
tumors of odontogenic epithelium
- ameloblastoma
- adenoid odontogenic tumor (AOT)
- calcifying epithelial odontogenic tumor (CEOT, Pindborg tumor)
mixed tumors of odontogenic epithelium and odontogenic ectomesenchyme
- ameloblastic fibroma
- ameloblastic fibro-odontoma
- odontoma
tumors of odontogenic ectomesenchyme
- odontogenic myxoma
2. cementoblastoma
T/F: ameloblastoma is benign but locally aggressive
true
clinical features of ameloblastoma
- painless
2. slow growing
T/F: the frequency of ameloblastoma equals combined frequency of all other odontogenic tumors
true
what gender predilection does ameloblastoma have?
no gender predilection
T/F: ameloblastoma usually expands rather than perforates bone
true
T/F: expansion from ameloblastoma can be dramatic
true
list the order of sites from most to least affected by ameloblastoma
- post mand (66%)
- mand PM region (11%)
- anterior mand (10%)
- anterior and posterior max (6%)
- max PM region (1%)
where does most ameloblastoma appear radiographically?
most in molar/ramus region of mand, but can occur anywhere
radiographic features of ameloblastoma
- unilocular/multilocular with well-defined but not sclerotic borders esp small lesions
- may displace teeth/resorb roots
what does multilocular expansile radiolucency due to ameloblastoma look like radiographically?
“soap bubble” or “honeycomb”
histopathologic features of ameloblastoma
- no enamel produced by lesional cells
- several different patterns
- tumor often infiltrates bony trabeculae (recurrence)
- tumor islands showing cuboidal or columnar cells at periphery
what does ameloblastoma resemble histopathologically?
ameloblasts of the enamel organ
what are the 2 most common patterns seen of ameloblastoma microscopically?
- follicular
2. plexiform
what is the center of tumor islands in ameloblastoma seen histopathologically composed of?
loosely arranged polyhedral epithelial cells that resemble stellate reticulum
what are the cubodial or columnar cells at the periphery seen histopathologically of ameloblastoma?
- ameloblast-like cells with reverse polarization
2. nuclei are polarized AWAY from the basement membrane
follicular pattern of ameloblastoma seen histopathologically
- islands with hyperchromatic, palisaded basal cells showing reverse polarization
- central zones resemble stellate reticulum
plexiform patter of ameloblastoma seen histopathologically
anastomosing cords of odontogenic epithelium
T/F: unicystic cysts can only be seen microscopically
true
what is the reason for en bloc resection of ameloblastoma?
insinuates through trabeculae
tx of ameloblastoma depends on what?
- size
2. site
tx of small ameloblastoma
aggressive curettage or small en bloc resection
tx of large ameloblastoma
large en bloc resection or segmental resection with reconstruction
why are maxillary ameloblastoma lesions tx’d more aggressively?
due to anatomic location (vital structures)
px of ameloblastoma
guarded
T/F: there is a higher recurrence of ameloblastoma if tx is simple curettage
true
T/F: ameloblastoma cannot be fatal
false, can be esp max lesions
T/F: it;s common for ameloblastoma to transform
false, rare
how many years after tx
ing ameloblastoma should a radiogrpahic follow-up be done for?
annual radiographic f/u for 8-10 yrs
periapical ameloblastoma
soft tissue variant of ameloblastoma
clinical features of periapical ameloblastoma
- gingival mass
2. less than 2 cm
what can periapical ameloblastoma look like clinically?
gingival bumps
T/F: peripheral ameloblastoma is symptomatic
false, asymptomatic
where does peripheral ameloblastoma usually affect?
mand, post
who is affected by peripheral ameloblastoma?
middle-aged adult
radiographic features of peripheral ameloblastoma
no radiographic findings…
no, or limited bone involvement (may have superficial erosion)
peripheral ameloblastoma is histopathologically similar to conventional ameloblastoma except what?
lesion is located under the surface epithelium
tx of peripheral ameloblastoma
biopsy is often curative if innocuous lesion
T/F: pts with AOT often have no change to their alveolar bone
true
clinical features of AOT
- can have expansion/swelling
2. asymptomatic
T/F: peripheral AOT (soft tissue) is common
false, rare
what is the gender predilection for AOT?
2:1 female predilection
what is the location predilection for AOT?
2:1 maxillary predilection
the most common site for AOT
anterior jaws
majority of AOT cases are associated with what?
impacted tooth
list the order from most to least common sites for AOT
- anterior max (53%)
- anterior mand (27%)
- max PM region (9%)
- mand PM region (7%)
- post max and mand (2%)
T/F: AOT is often an incidental finding on radiographs
true
radiographic features of AOT
- well-circumscribed unilocular radiolucency
- ± radiopaque flecks
- often causes divergence of adjacent roots
- pericoronal lucency may extend apically beyond CEJ
histopathologic features of AOT
- well-developed capsule
- swirling spindle-cell nests and duct-like structures “adenomatoid”
- foci basophilic calcified material may be seen
tx of AOT
enucleation
prognosis of AOT
excellent
T/F: recurrence of AOT is common
false, rare
what is calcifying epithelial odontogenic tumor (CEOT) also known as?
Pindborg tumor
before CEOT was described by Pindborg in 1956, what was it probably confused with?
ameloblastoma
histogenesis of CEOT presumes what?
stratum intermedium
Is CEOT common?
no, rare
what is the gender predilection for CEOT?
no gender predilection
what is the location predilection for CEOT?
2:1 mand, usually posterior
clinical features of CEOT
- may have expansion
2. asymptomatic
what is CEOT associated with?
impacted tooth
list the order from most to least common sites for CEOT
post mand (57%) > post max (21%) > anterior mand (14%) > anterior max (8%)
radiographic features of CEOT
- well-circumscribed radiolucency when small, multilocular when enlarges
- margins well-defined but may be ill-defined
- ± radiopaque flecks
what is the pattern of the radiopaque flecks seen with CEOT?
“driven snow” pattern
histopathologic features of CEOT
- proliferation of polyhedral epithelial cells with eosinophilic cystomplasm
- nuclei frequently pleomorphic
- rare mitoses
- calcifications
the epithelial cells seen with CEOT histopathologically is associated with what?
amyloid (eosinophilic, homogenous)
what are the calcifications of CEOT seen histopathologically called?
Liesegang rings (lamellated)
tx of CEOT
- conservative excision
2. periodic radiographic follow-up
T/F: radical surgery is warrented in tx’ing CEOT
false, is not
px of CEOT
good
